轮机英语多媒体课件2

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1、 第二章船舶辅助机械第二章船舶辅助机械1090 A vane pump belongs to _ according to its working principle. 根据工作原理，叶片泵属于容积式泵。 A. reciprocating pump B. positive displacement pump C. centrifugal pump D. centripetal pump1091Through a _ pump, the liquid is transferred from the suction to the 1092 discharge by the mechanical v

2、ariation of the volume of a chamber or chambers. 对于容积式泵，液体通过泵腔室体积的改变从吸入口排至排出口。 A. positive displacement B. ejector C. centrifugal D. air compressor1092 A mono-pump is a single-screw pump. That means it consists of _ rotor(s). 单螺杆泵只有一个转子。 A. one B. two C. three D. four1093 The gear and screw pumps ar

3、e classified as _ 齿轮泵和螺杆泵都属于容积式泵。 A. variable stroke pumps B. multistage pumps C. positive displacement pumps D. triple-ported pumps1094 Gear pumps are of positive displacement type pumps because they discharge a near constant amount of liquid _ pressure.不管压力如何，齿轮泵的排量几乎恒定。 A. depending on B. in rela

4、tive to C. regardless of D. because of 1090 B 1091 A 1092 A 1093 C 1094 C1095 A gear pump belongs to _ according to its working principle. 根据工作原理，齿轮泵属于容积式泵。 A. reciprocating pumps B. positive displacement pumps C. centrifugal pumps D. centripetal pumps1096 The pressure head of a pump is given in the

5、 unit of _ 泵的压头常用“米液柱高度表示。 A. kg B. MPa C. meter fluid colunm D. None of the above is true.1097 A centrifugal pump produces the required pressure energy by means of a rotating_ provided with vanes.离心泵通过旋转带有叶片的叶轮来产生压力能。 A. propeller B. impeller C. circumference D. screw1098 The discharge flow of a re

6、ciprocating pump is_ 往复泵的排量具有脉冲性。 A. steady B. in pulsation C. continuous D. large1099 In a _ the center screw is driven and the outer screws idle. A. single screw pump B. double-screw pump在三螺杆泵中，只有中间螺杆被驱动。 C. triple screw pump D. centripetal pumpA Screw pump belongs to _ according to its working pr

7、inciple. 根据工作原理，螺杆泵属于容积式泵。 A. reciprocating pumps B. positive displacement pumps C. centrifugal pumps D. centripetal pumps 1095 B 1096 C 1097 B 1098 B 1099 C 1100 B 1101 The amount of fluid delivered by a screw pump can be regulated by _ 齿轮泵属于容积式泵，排量只能通过改变转子的速度来调节。 A. throttling the pressure line B.

8、 changing the speed of the rotor C. either A or B D. None of the above is true.1102 While flowing through the volute in a centrifugal pump, part of the _ energy of the liquid is converted to _ energy. 当液体经过离心泵的涡壳时，局部动能转换成压力能。 A. kinetic/pressure B. kinetic/essential C. pressure/kinetic D. pressure/h

9、eight 1103 The amount of fluid delivered by a centrifugal pump can be regulated by _ 离心泵的排队量可通过改变压力来调节，出可通过改变转子的速度调节。 A. throttling the pressure line B. changing the speed of the rotor C. either A or B D. None of the above is true.The amount of fluid delivered by a reciprocating pump can be regulate

10、d by _ 往复泵属于容积式泵，排量通过改变柱塞的速度来调节。 A. throttling the pressure line B. changing the speed of the piston C. either A or B D. None of the above is tree.1105 The amount of fluid delivered by a positive displacement pump can be regulated by _对于容积式泵，排量只能通过改变转子的速度来调节。 A. throttling the pressure line B. chang

11、ing the speed of the driving rotor C. either A or B D. None of the above is true. 1101 B 1102 A 1103 C 1104 B 1105 B 1106 Which of the following pumps are seE-priming, and can deal with hquid from a level below the pump? reciprocating; rotary; centrifugal. 往复泵和旋涡泵都具有干吸能力，而离心泵没有。 A. only B. and C. an

12、d D. and 1107 The amount of fluid delivered by a helical pump can be regulated by _ 螺旋泵属于容积式泵，排量只能通过改变转子的速度来调节。 A. throttling the pressure line B. changing the speed of the rotor C. either A or B D. None of the above is true. 1108 A positive displacement pump is that where the volume of the pump cha

13、mber is alternately increased to _ and then decreased to 对于容积式泵，泵腔室体积增大时吸人液体，体积减少时那么排出液体。 A. draw the liquid in/force the liquid out B. force the liquid out / draw the liquid in C. suction/draw D. deliver/outletThrottling in the _ line of a centrifugal pump involves the risk of the pump cavitation.对

14、于离心式泵，节流吸人管路，会产生气蚀危险。 A. suction B. exhaust C. pressure D. discharge 1110 As for a hydraulic single action vane pump, the inner wall of the stator is usually of _ shape.对于液压单作用叶片泵，静子的内壁通常是圆形。 A. circular B. elliptical C. rectangular D. hexagon 1106 B 1107 B 1108 A 1109 A 1110 A l111 As for a hydraul

15、ic vane pump, which of the following is in contact with the vanes during working: the rotor; the pump shaft; the external surface of the housing. 对于液压叶片泵，工作时，转子与叶片接触。 A. only B. only C. and D. and l l 12 Shaft sealing in a centrifugal pump can be effected by _ 离心泵的轴封可用机械密封，也可用填料箱。 A. the mechanical

16、seal B. packed stuffing boxes C. either A or B D. neither A nor Bl 113 A reciprocating pump belongs to _ according to its working principle. 根据工作原理，往复泵属于容积式泵。 A. injector pumps B. positive displacement pumps C. centrifugal pumps D. centripetal pumps1114 A _ pump is that where the volume of the pump

17、chamber is alternately increased to draw the liquid in and then decreased to force the liquid out. 对于容积式泵，泵腔室体积增大时吸人液体，体积减少时那么排出液体。 A. injector B. positive displacement C. centrifugal D. centripetal1115 What is the purpose of a relief valve? 释放阀可用来当排出阀关闭时将液体回流到吸人侧。 A. to fill 2 tanks at the same tim

18、e B. to use pump at a higher pressure C. to return liquid to suction side if discharge valve is closed D. All of the above are true. 1111 A 1112 C 1113 B 1114 B 1115 C1116 The pump discharge pressure will be considerably higher than the pressure at the _泵的排出压力比泵进口支管的压力要高得多。 A. pump entry branch B. o

19、utlet pipe C. impeller D. None of the above is tree.1117 Which of the following pumps belongs to centrifugal- pump? 扩压式泵属于离心式泵。 A. Piston pump B. Screw pump C. Diffuser pump D. Water-ring pump1118 The volute pump is one in which the impeller _对于旋涡泵，叶轮将液体排至渐渐变宽的流道。 A. discharges into a gradually wide

20、ning channel B. has stationary diffuser vanes C. produces no kinetic energy D. All of the above are true.1119In _ pumps a closed discharge valve will cause bursting discharge pressure.1120 柱塞泵是容积式泵，排出阀关闭将会产生具有破坏性的压力。 1121 A. centrifugal B. plunger C. injector D. water11221120 Which of the following

21、pumps are self-priming, and can deal with liquid from a level below the pump; ejector; screw; centrifugal.1123 喷射泵和螺杆泵都具有干吸能力，而离心泵没有。 1124 A. only B. and C. and D. and 1125 1116 A 1117 C 1118 A 1119 B. 1120 B1121 The amount of fluid delivered by a gear pump can be regulated by _ 齿轮泵属于容积式泵，排量只能通过改变转子

22、的速度来调节。 A. throttling the pressure line B. changing the speed of the rotor C. either A or B D. None of the above is true1122 Attempts are made to eliminate axial thrust in centrifugal pump by _ 消除离心泵的轴向力，可使用具有平衡孔的叶轮，也可使用对称叶轮。 A. providing the impeller with balancing holes B. the use of symmetrical i

23、mpeller C. neither A nor B D. either A or B1123 Which of the following pumps will build up a bursting pressure or stall their motors if the discharge valves are closed? gear; . centrifugal; . screw. 齿轮泵和螺杆泵都是容积式泵，排出阀关闭将会产生具有破坏性的压力，而离心泵不会。 A. and B. and C. and D. and 1124Which of the following operat

24、ing features do displacement pumps bear if they are 1125 working under no-cavitation condition? . output is almost directly proportional to speed; . they are self-priming; . they will develop a discharged pressure equal to the resistance to be overcome, irrespective of speed. 容积式泵正常工作时具有以下特性：排量几乎与转速

25、成正比；具有自吸能力；不管速 度如何，都能产生大小等于需克服阻力的排出压力。 A. and B. and C. and D. and 1125 The _ pump discharges a nearly constant amount of liquid regardless of pressure.不管压力如何，容积式泵的排量几乎恒定。 A. mixed-flow B. axial-flow C. centrifugal D. displacement 1121 B 1122 D 1123 C 1124 D 1125 D 1126 Which of the following pumps

26、is used where a relatively high pressure and small capacity are required?往复泵一般用于高压头、小排量的场合。选项C应是“reciprocating pump。 A. Volute pump B. Diffuser pump C. Regenerative pump D. All of the above 1127 Some pumps use packing as sealing gland. The gland should be _ 一些泵使用填料作为密封格兰，注意要少许松一点，让液体稍微泄漏。 A. slack e

27、nough to allow slight leakage of fluid B. slightly clocked C. brought up tight so as not to allow any leakage D. fitted with a relief valve 1128 Air chambers are usually fitted to reciprocating pumps in order to _ 往复泵中的空气室用来保持流量稳定。 A. increase discharge pressure B. increase suction vacuum C. develop

28、 pulsation flow D. keep a steady rate of flow1129 The pipe friction and the resistance will _ as a result of an increase in the amount of fluid flowing through the system. 系统流量增加时，管路摩擦和阻力将增大。注意“rise与“raise之区别。 A. reduce B. rise C. raise D. fall1126 C 1127 A 1128 D 1129 B1130 Which of the following w

29、ill be the advantage of a centrifugal pump as compared with a reciprocating pump? Its discharge is continuous; It has no internal valves; Upon accidental closing of discharge valve, excessive pressure will not build up.离心泵与往复泵相比具有以下优点：排量连续；无内部阀件；如果排出阀关闭，不会产生过高的压力。 A. B. C. D. only1131 Which of the f

30、ollowing pumps are self-priming, and can deal with liquid from a level below the pump: reciprocating ; vane; gear. A. only B. and C. and D. and 往复泵、齿轮泵和叶片泵都具有干吸能力。1132 Centrifugal pumps can be designed with a number of impellers _ to attain a high final delivery pressure.离心泵通过几个叶轮串联，可提高其排出压头。 A. in

31、series B. in parallel C. either A or B D. None of the above is true1133 If an operating auxiliary boiler has a water pH reading of 7, you should _ 如果辅助锅炉给水的pH值是7，那么应使用氢氧化钠进行处理，使pH值在10左右； A. bottom blow the boiler B. treat the water with catstic soda C. treat the water with chemical scavengers D. red

32、uce the water alkalinity to recommended readings1130 C 1131D 1132 A 1133 B1134 The internal part of the boiler, if found _ , has to be chemically washed by yard. 锅炉内侧发现水垢，应化学清洗。 A. deformed B. rusted C. cracked D. scaled1135 The internal part of boiler should be welded by yard if found _ 锅炉内侧发现裂纹，应电

33、焊修理。 A. scaled B. cracked C. shape changed D. deformed1136 The tube in a boiler should be blinded if found _锅炉管子发现泄露，应封死。 A. sealed B. informed C. leaky D. deformed 1137 In a _ boiler the water flows through the inside of the tubes while the hot gases pass around the outside.对于水管锅炉，水在管子内流动，而高温气体在管子外

34、流动。 A. water-tube B. fire-tube C. exhaust gas D. none of the above 1138 In a _ boiler the hot gases from the furnace pass through the tubes while the water is on the outside. 对于火管锅炉，高温气体在管子内流动，而水在管子外流动。 A. water-tube B. fire-tube C. exhaust gas D. None of the above is tree. 1139 _ are mounted in pai

35、rs to protect the boiler against overpressure. 锅炉安装平安阀以防锅炉超压。 A. Safety valves B. Water tube C. Steam stop valves D. Blow down valves1140 The furnace of a oil fired boiler should be _ before the operating burner is lit.锅炉点火前，应进行扫气。“purge意“驱气；而“clear of air“去除空气。 A. filled with water B. purged C. cle

36、ared of air D. None of the above is true 1134 D 1135 B. 1136 C 1137 A 1138 B 1139 A 1140 B1141 When steam is being raised on a boiler, the water level will normally _ 锅炉开始运行时，水位将随锅炉温度的提高而升高。 A. drop as the boiler warms up B. rise as the boiler warms up C. remain unchanged until the boiler is hot eno

37、ugh D. rise and fall with the steam demand1142 The donkey boiler may be given a bottom blow _锅炉熄火后，可进行下排污。 A. to raise water level B. only while making steam C. to remove scum D. when fire are secured1143 The water level in a steaming auxiliary boiler will always _ 辅助锅炉的水位：降随蒸汽需求量的变化而变化。 A. rise whe

38、n the steam pressure is increased B. remain constant as long as the feed pump operates C. fall when the steam pressure is decreased D. vary as the steam demand changes1144 The boiler feed water check valves are located on the _锅炉给水单向阀门位于给水管路中。 A. feed pump suction line B. hot well C. shell of the fe

39、ed heater D. feed lines to the boiler1145 If in doubt as to the tree water level when a boiler is being oil-fired, you should _ 烧油锅炉运行时，对真实水位没有把握时，应尽快熄火。 A. take no measures B. extinguish the fire as soon as possible C. feed water to the boiler D. open the blow down valve 1141 B 1142 D 1143 D 1144 D

40、 1145 B1146 The boiler feed pump discharge pressure is higher than the steam dnnn pressure to _ A. ensure feed water flow into the boiler B. keep the steam drum pressure high C. prevent water hammer in the feed line D. help the feed water flash to steam 锅炉给水泵排出压力比蒸汽筒压力要高，才能确保给水进人到锅炉。1147 Safety valv

41、es on a boiler vent to the _锅炉平安阀通大气。 A. fuel tank B. bilge C. atmosphere D. auxiliary exhaust hne1148 A donkey boiler is _辅锅炉即辅助性锅炉。 A. one to supply steam to the main propulsion turbine B. an auxiliary boiler C. A and B D. neither A nor B1149 The safety valves should be tested and adjusted when th

42、e boiler survey is _ 当进行锅炉检验时，应对锅炉平安阀作试验和调整。 A. completed B. carried out C. cleaned D. steamed1150 You should frequently compare dram-mounted and remote-reading water level indicators. _ between these have contributed to failures because of overheating through shortage of water, when a boiler was be

43、ing oil-fired.锅筒旁的水位指示器与遥控水位指示器的读数要经常进行比较，两者的偏差会成为锅炉运行故障(因缺水而过热)的原因。 A. Descriptions B. Discrepancies C. Different D. Deflections 1146 A 1147 C 1148 B 1149 B 1150 B 1151 Impurities from the boiler water surface can be removed through the _ 锅炉水面的杂质可通过上排污阀去除。 A. safety valve B. blow down valve C. scum

44、 valve D. feed check valve1152 In motor ship, _ is often used to recover some of the heat carried in the exhaust gases from the main engine .在内燃机船上，装备废气锅炉用来回收主机废气携带的热量 A. an diesel oil heater B. a waste heat boiler C. a fresh water generator D. all the above1153 _ will be used to blow away the combu

45、stion products from the tube surfaces. A. The blow down valve B. The scum valve C. The air release cock D. The soot-blower 吹灰器用来吹除管子外表的燃烧产物。 1154 Latent heat changes the _ of water.潜热能改变水的物理状态。 A. physical state B. temperature C. atmospheric pressure D. sensible pressure 1155 The amount of heat rele

46、ased by steam when it changes to water at the same temperature is called _在同样的温度下，蒸汽变成水时所释放的热量，称为冷凝潜热。 A. latent heat of condensation B. latent heat of vaporization C. latent heat of saturation D. sensible heat of condensation 1151 C 1152 B 1153 D 1154 A 1155 A 1156As for an oil-fired boiler if at a

47、 normal steaming condition and water 1157 goes out of sight in gauge glasses the action you should take is: secure oil to fires; )increase feed pump pressure.1158 发现锅炉水位表断水，应立即熄火，而不能盲目地增大给水泵的压力。 1159 A. B. and C. D. neither and 11601157 As for a oil-fired boiler too much air would indicated by _ 116

48、1 对于烧油锅炉，空气过多，火焰呈亮白色。1162 A. yellowish flame B. golden yellow flame1163 C. milky flame D. brilliant white flame11641158 W.H. R stands for _ WHR代表废热回收装置。1165 A. Water Head Register B. Water Heater Re-circulating1166 C. Waste Heat Recovery D. Waste Handle Reference11671159 When the boiler load returns

49、 to normal, the drum pressure will rise and steam bubble formation will reduce, causing a fall in water level. This is known as _当锅炉负荷回到正常时，锅筒压力上升，气泡减少，水位下降。这种现象被称为“收1168 缩。 A. swell B. shrinkage C. flash off D. lack of water11691160 A dazzling white burner flame in the boiler furnace indicates _ 11

50、70 A. no combustion B. deposits in the fuel见第1157题。1171 C. excessive air in the fuel D. cold fuel oil1172 1156 A 1157 D 1158 C 1159 B 1160 C1161 The water level showing in a boiler water gauge glass is usually _ during working. A. higher than the actual drum water level B. equal to the actual drum w

51、ater level C. increasing due to steam condensation in the glass D. lower than actual drum water level锅炉运行期间，水位表显示的水位比锅筒实际水位要低。这是因为锅炉水是水和汽 泡的混合物(水位表本身上端通汽下端通水)，向锅炉供水后，等汽泡凝结，水位反而下降。Which of the following may hardness of the boiler water cause? scale formation; tube failure; corrosion.炉水硬度会引起水垢，管子损坏以及腐

52、蚀等问题。 A. and B. and C. and D. and 1163 The separation of impurities and water from _ is essential for good combustion of diesel engines.从燃油中去除杂质和水分，这对柴油机发火燃烧很重要。 A. lube oil B. fuel oil C. turbine oil D. grease1164 High-speed rotation in a centrifugal purifier can produce a force _ the force of grav

53、ity.离心式分油机高速旋转时产生的离心力比重力大几千倍。 A. many thousand times larger than B. the same as C. many thousand times smaller D. none of the above1165 _ are used to ensure that ships dont discharge oil when pumping out oily water from any oil contaminated space. 船舶上的油水别离器能保证船舶排放舱底水等污水时不排油。 A. Boiler B. Incinerator

54、 C. Oily water separator D. Sewage treatment unit 1161 D 1162 D 1163 B 1164 A 1165 C1166 Oil water separators are used to ensure that ships don t discharge oil when pumping out _见上题。 A. ballast water B. boiler water C. bilge water D. sewage water1167 The bilge main is mamlged to drain any watertight

55、 compartment _ ballast, oil or water tanks and to discharge the contents overboard.舱底水总管设计用来排放除了压载舱、燃油舱和水舱之外的任何水密空间的污水到 舷外。otherthan=except。 A. rather than B. other than C. in addition that D. except for1168 Emulsification of oil will occur when mixed with _油与水混合后会产生乳化。 A. air B. black oil C. water

56、D. ice cream1169 A centrifuge arranged to separate two liquids is known as _ 离心式分油机设计用来别离两种液体时，被称为分水机。 A. an oily water separator B. a purifier C. a centrifugal compressor D. a clarifier1170 A centrifuge arranged to separate impurities and small amounts of water from oil is known as _离心式分油机设计用来别离油中的

57、杂质和少量水时，被称为分杂机。 A. an oily water separator B. a purifier C. a centrifugal compressor D. a clarifier 1166 C 1167 B 1168 C 1169 B 1170 D1171 When a clarifier is running the impurities and water collect at the bowl _ 分杂机运行时，由于杂质比重较大，积聚在别离筒的四周。 A. center B. periphery C. inlet D. upper parts1172 For many

58、 years marine centrifuges were designed for _ operation, that is the machines were run for a period during which solids accumulated in the bowl. The machine was stopped when the accumulated solids began to impair its performance.很多年以来，离心式分油机被设计成分批运行。意即，分油机运行一段时间，固体杂质积聚在别离筒内，当分油机停止运行时，才开始排渣。 A. purif

59、ying B. batch C. long period D. temporary1173 For a purifier, changing to a gravity disc with larger hole diameter will move the interface towards the _对于分水机，使用较大直径的比重环，油水界面会向别离筒四周移动。 A. bowl periphery B. bowl center C. upper surface D. lower surface1174 For a purifier changing to a gravity disc wit

60、h smaller hole diameter will move the interface towards the _对于分水机，使用较小直径的比重环，油水界面会向别离筒中心移动。 A. bowl periphery B. bowl center C. upper surface D. lower surface1175 In an oily water separator the oil will travel _ to the oil collecting spaces.在油水别离器中，油是向上运动到集油室的。 A. upwards B. downwards C. outwards D

61、. forwards 1171 B 1172 B 1173 A 1174 B 1175 A1176 When started, a complete oily water separating unit is first filled _ . The oily water mixture is then pumped through the inlet pipe into the coarse separating compartment. 油水别离器开始工作时应首先注满清水。 A. with dirty water B. with clean water C. by oily water D

62、. by mixed water1177 A high rate of separation between oil and water is favored by _ 油滴尺寸大，将有助于油、水别离。 A. large size of oil globule B. low temperature C. high viscosity D. high flow rate1178 A hydraulic motor may be driven by _液压马达是由油来驱动的。 A. an electric motor B. a diesel engine C. a compressor D. oi

63、l1179 In a hydraulic system , _ are used to protect the system from over pressure. 在液压系统中，平安阀用来防止系统超压。 A. stop valves B. check valves C. safety valves D. reducing valves1180 _ are used for cargo handling.回转式起货机(克令吊)可用来进行货物装卸。 A. Cranes B. Mooring winches C. Windlasses D. Foreman 1176 B 1177 A 1178 D

64、 1179 C 1180 A1181 Among the basic categories of equipment, which of the following are used to allow the hydraulic energy to be controlled?在液压系统中，液压阀可实现对液压能的控制。 A. hydraulic pumps B. valves C. hydraulic cylinders D. hydraulic motors1182 _ are used to handle anchors and chains.锚机可用来控制锚和锚链。 A. Cargo w

65、inches B. Mooring winches C. Windlasses D. Cargo hatches1183 The drive motor will have a brake annged to fail-safe, i.e. it will _ the load if power fails or machine is stopped.起货机的驱动马达具有制动装置进行故障平安保护，当失电时它能支住货物。 A. lift B. put C. take D. hold1184 _ are used for hauling in or letting out the wires wh

66、ich fasten the ship to the shore.绞缆机能收进或放出缆绳。 A. Cargo winches B. Mooring winches C. Windlasses D. Cargo hatches1185 The drive motor will have a brake arranged to fail-safe, i.e. it will _ the load if power fails or machine is stopped. 见第1183题。 A. cast B. put C. hold D. let out 1181 B 1182 C 1183 D

67、1184 B 1185 C 1186 Among the basic categories of equipment, which of the following are used to convert mechanical into hydraulic energy7 在液压系统中，液压油泵将机械能转变为液压能。 A. The hydraulic pumps B. Valves C. Hydraulic cylinders D. Hydraulic motorsl 187 Among the basic categories of equipment, which of the follo

68、wing is used to convert hydraulic energy into continuous rotary motion.? 在液压系统中，液压马达将液压能转变为持续的回转运动。 A. Hydraulic pumps B. Valves C. Hydraulic cylinders D. Hydraulic motors1188 _ are used to limit the pressure in any particular portion and mainly control the pressure after the valve.减压阀可用来限制压力，它主要是控制

69、阀后的压力。 A. Relief valves B. Check valves C. Safety valves D. Reducing valve1189 The rotor of the hydraulic motor rotates at a speed proportional to the _ 液压马达转子的回转速度与油量有关，而与油压无关。 A. flow of oil B. pressure of oil C. A and B D. temperature of oil1190 What type of valve is used to direct the flow of hy

70、draulic fluid?方向控制阀用来引导液压流体的方向。 A. Relief valve B. Direction control valve C. Stop valve D. Pressure control valve 1186 A 1187 D 1188 D 1189 A 1190 B1191 External and internal leakage in hydraulic systems may be caused by _ 异常振动、部件过度磨损、油压异常等都会引起液压系统内外泄露。 A. unusual vibration B. excessive worn parts

71、C. abnormal pressure D. any of the above1192 In a general cargo crane, _ is fitted to raise or lower the jib. 在回转式起货机(克令吊)中，变幅装置用于调节吊臂的高度。 A. the slewing motor B. the luffing motor C. the hoisting motor D. none of the above1193 Among the basic categories of equipment, which of the following are used

72、 to convert the hydraulic energy into linear motion? 在液压系统中，液压油缸将液压能转变为柱塞的线性运动。 A. Hydraulic pumps B. Valves C. Hydraulic cylinders D. Hydraulic motors1194 The single acting cylinder is the simplest form where pressure is applied to the full area of the piston head to move the load through piston ro

73、d extension. The load causes rod _ when the drive pressure is released.单作用式油缸是最简单的形式，压力作用于整个柱塞头部，通过柱塞杆的伸展传递负荷。当驱动压力释放后，负荷将会引起柱塞杆收进。 A. contraction B. retraction C. expansion D. shrinkage1191 D 1192 B 1193 C 1194 B 1195 A1195 In a ordinary cargo crane, _ is fitted to rotate the crane. 在回转式起货机(克令吊)中，回

74、转装置用于旋转克令。 A. the slewing motor B. the luffing motor C. the hoisting motor D. none of the above1196 The crane is usually mounted on a pedestal to offer adequate _ to the operator. 回转式起货机(克令吊)一般安装在平台上，确保向操作者提供足够的视野。 A. time B. space C. length D. visibility1197 In a general cargo crane, _ is fitted to

75、 lift the cargo load. 在回转式起货机(克令吊)中，提升装置用于装卸货物。 A. the slewing motor B. the luffing motor C. the hoisting motor D. none of the above1198 When the union purchase derrick is operated, one derrick is positioned over the quayside and the other almost vertically over the _ 在吊杆式起货机中，一根吊杆位于码头上方，另一根几乎垂直地位于货

76、舱的上方。 A. dock B. hold C. pedestal D. machinery space1199 Cargo handling unit is rated according to the _ to be lifted.货物装卸装置是根据装卸的平安工作负荷标定的。 A. cargo crane B. jib C. safe working load D. oil pressure 1196 D 1197 C 1198 B 1199 C 1200 B1200 _ play a very important part in hydraulic systems by preventi

77、ng int6raction between different parts of the hydraulic circuit. 在液压系统中，单向阀起很重要的作用，它能防止液压油路中不同部件之间相互影响。 A. Motors B. Check valves C. Safety valves D. Reducing valve1201 Which of the following can be used in hydraulic transmission system? 液压系统中采用液压油。A. Hydraulic oil B. Animal oil C. Light oil D. Fuel

78、 oil1202 _ is the production of pure water from sea water by evaporation and re-condensing 通过蒸发和再冷凝，由海水产生淡水的过程称为“蒸馏。 A. Evaporation B. Circulation C. Condensation D. Distillation1203 When a vacuum boiling evaporator works, the hot jacket water will pass over the tube stack and _ the sea water passin

79、g through the tubes. 当真空蒸发式造水机工作时，气缸冷却水经过热交换器(海水加热器)，给管内流动的海水加温。 A. dispose B. dissolve C. heat D. dissipates1204 With a vacuum boiling evaporator, the remainder of sea water fed to the evaporator is pumped out by _对于真空蒸发式造水机，剩余的海水由排盐泵排出。 A. a brine pump B. an air ejector C. a feed pump D. distillat

80、e pump 1205 In a vacuum boiling evaporator, the fresh water generated is pumped out by _ 对于真空蒸发式造水机，产生的淡水由凝水泵泵出。A. a brine pump B. an air ejector C. a feed water pump D. a condensate pump 1201 A 1202 D 1203 C 1204 A 1205 D1206When distilling sea water the cooling water discharging from the distiller

81、 is fed1207 back to evaporator as feed water _1208当蒸馏海水的时候，蒸馏器排出的冷却水被返回到蒸发器作为给水，其目的是为了向蒸发器提供温度较高的水，以提高造水机运行的经济性。1209 A. to decrease scale formation B. for better cooling effect1210 C. for more economical purpose D. to raise vacuum1211 1207 When distilling salt water the cooling water discharging fro

82、m the distiller is fed back to evaporator as feed water _见上题。1212 A. to cut down the amount of cooling water needed1213 B. to prevent an excess amount of cooling water from being discharged to the bilges1214 C. to supply hot water to the evaporator for more economical operation1215 D. None of the ab

83、ove is tree.1216 1208 The process during which liquid containing a reasonable amount of sensible heat at a particular pressure immediately changes into steam after admitted to a chamber at a lower pressure is called _1217在特定的压力下，具有一定显热的液体进人到压力较低的腔室时，迅速地变成蒸汽这一过程被称为“闪蒸。闪发式造水机就是基于此原理。1218 A. boiling of

84、f B. flash evaporation C. condensation D. none of the above1219 1206 C 1207 C 1208 B 1209 Compressed air is used on board ship _压缩空气的作用有：启动柴油机、用于气动控制系统、用于气开工具等。 A. for starting diesel engines B. in pneumatic control system C. in pneumatic tools D. All the above are true.1210 The starting air bottle

85、should be pumped up to maximum pressure by the _ before start of the engine.在发动机启动前，应使用空气压缩机将启动空气瓶泵至最大压力。 A. air compressor B. refrigeration compressor C. vacuum pump D. purifier1211 The primary task of the compressed air system is to deliver the starting air necessary for _压缩空气系统的首要任务是为启动主机输送压缩空气。

86、A. starting the M.E. B. starting the emergency electric alternator C. driving the main turbine D. driving the turbocharger1212 The evaporating pressure in R22 vapor compression refrigeration plant should be _ atmospheric.22制冷装置中，蒸发压力应稍高于大气压，以防空气渗入。 A. below B. above C. equal to D. much larger than12

87、13 Hot gas defrosting uses the hot gas from _ to defrost the evaporator. 在制冷装置中，一般使用来自于制冷压缩机的高温气体对蒸发器化霜。 A. starting air bottles B. diesel engines C. boilers D. refrigeration compressors 1209 D 1210 A 1211 A 1212 B 1213 D1214 In a refrigeration plant the _ need defrosting.在制冷装置中，蒸发器最易结霜，需要化霜。 A. fan

88、 B. compressor C. condenser D. evaporator1215 What is the substance called which can readily be converted from a liquid into a vapor, and also from a vapor into liquid with a reasonably narrow range of pressure? 在一定的压力范围内，能从液体变成气体，又能从气体变成液体的物质，被称为“制冷剂。 A. Refrigerator B. Refrigerant C. Cooling mediu

89、m D. Brine1216 A fluid coil will _ large quantities of heat when it changes state from a liquid to a vapor.当液体变成蒸汽时，流体的盘管将吸收热量(如在蒸发器中)。 A. release B. absorb C. develop D. regenerateA fluid coil Will _ large quantities of heat when it changes state from a vapor to a liquid.当蒸汽变成液体时，流体的盘管将放出热量(如在冷凝器小)

90、。 A. release B. absorb C. develop D. regenerate1218 The latent heat of evaporation is dissipated in the _ in a compression refrigeration system.在压缩式装置中，蒸发潜热是在冷凝器中释放给海水的。 A. evaporator B. condenser C. expansion valve D. compressor 1214 D 1215 B 1216 B 1217 A 1218 B1219 A refrigerant boils and vaporiz

91、es in the _ in a compression refrigeration system. 在压缩式装置中，制冷剂是在蒸发盘管或冷却盘管中沸腾和蒸发的。 A. liquid receiver B. compressor C. condenser D. cooling coil1220 A refrigerant gives up heat when it goes through当制冷剂经过冷凝器时释放热量。 A. condenser B. regurgitate C. evaporator D. boil coil1221 It should be ensured that onl

92、y _ vapor is handled by the refrigeration compressor.应确保进入到制冷压缩机的制冷剂气体是干蒸汽，以防液击。 A. humidity B. dry C. steam D. oil1222 In the refrigeration compressor the temperature of the vapor is _ by compression. 在制冷压缩机中，气体的压力因被压缩而提高。 A. raised B. risen C. reduced D. maintained constant1223 If the capacity of

93、the refrigeration compressor is too small, the excess vapor will accumulate in the evaporator, causing the pressure to _如果制冷压缩机的容量太小，过多的蒸汽将会积聚在蒸发中，引起压力升高 A. rise B. fall C. be maintained constant D. None of the above is true.1224 If the capacity of the refrigeration compressor is too large, the satu

94、ration temperature will _如果制冷压缩机的容量太大，饱和温度将下降。 A. rise B. fall C. be maintained constant D. None of the above.1219 D 1220 A 1221 B 1222 A 1223 A 1224 B1225 In the process of _ , liquid changes into gas. 在蒸发过程中，液体变成气体。 A. evaporation B. frosting C. condensing D. compressing1226 Since heat will not fl

95、ow freely from a body at a _ temperature to another at a _ temperature, it is necessary to expend mechanical work, heat, or electrical energy from an external source to achieve refrigeration. 众所周知，热量不能自发地从低温物体传递到高温物体。 A. lower/higher B. shallower/deeper C. larger/smaller D. higher/lower1227 In a com

96、pression refrigeration plant the refrigerant flows from the expansion valve and through the _ where it absorbs heat from the space being cooled and becomes a gas or vapor. 在压缩式制冷装置中，制冷剂通过膨胀阀后到达蒸发器，在蒸发器中，制冷剂吸收热量而变成气体。A. compressor B. condenser C. throttle valve D. evaporator1228 The _ compressor and

97、its electrical motor are entirely housed in a gas-tight casing. 封闭式压缩机和电动马达被整体封闭在气密外壳内。 A. open-type B. hermetic C. A and B D. None of the above.1229 The heat used to change a liquid to a vapor is called _ 将液体转变成蒸汽的热量，称为蒸发潜热。 A. latent heat of fusion B. latent heat of vaporization C. specific heat o

98、f vaporization D. latent heat of the gas1230Both the temperature and the pressure of the refrigerant are increased in the _ 1231在制冷压缩机中，制冷剂的温度和压力都升高。1232 A. compressor B. condenser C. evaporator D. expansion valve1233 1225 A1226 A 1227 D 1998 B 1999 B 1230 A1931 The compressor suction line conveys t

99、he refrigerant vapor from _ to _ 压缩机吸人管路将制冷剂蒸汽从蒸发器输送到压缩机。 A. condenser/evaporator B. evaporator/compressor C. compressor/condenser D. None of the above.1232 The thermal expansion valve controls the amount of refrigerant that is allowed to flow to the _热力膨胀阀用来控制流向冷却盘管的制冷剂量。 A. compressor B. cooling c

100、oils C. condenser D. receiver1233 When the temperature of the refrigerant flowing out from the condenser is below the condensing temperature, it is said to be _当冷凝器出口的制冷剂温度低于冷凝温度时，我们称它为“过冷。 A. dry B. wet C. super-cooled D. superheated1234 During working, thermostatic expansion valve should be _ 在工作过

101、程中，热力膨胀阀是根据负荷来实现制冷剂节流的。 A. either all the way open or all the way closed B. normally fully open C. throttled depending on load D. controlled by liquefied pressure1235 The expansion valve on a Freon system controls the _ 制冷系统中的膨胀阀可用来控制蒸发器出口的蒸汽过热度。 A. superheat of the gas leaving the compressor B. bac

102、k pressure in the evaporator C. temperature of the icebox D. superheat of the gas leaving the evaporator 1231 B 1232 B 1233 C 1234 C 1235 D1236 A feeler or thermal bulb is used for the expansion valve to _ 热力膨胀阀中，使用温包来检测温度。 A. detect the temperature B. detect the pressure C. heat the refrigerant D.

103、accelerate the refrigerant1237 In a compression refrigeration plant the refrigerant is under low pressure in the and under high pressure in the _在制冷装置中，制冷剂在蒸发器中处于低压，而在冷凝器中处于高压。 A. compressor/condenser B. condenser/evaporator C. throttle valve/evaporator D. evaporator/condenser1238 The boiling and co

104、ndensation points of refrigerant mainly depend on the _ exert- ed upon it.制冷剂的蒸发温度和冷凝温度取决于压力(蒸发压力和冷凝压力)。 A. temperature B. density C. volume D. pressure1239 The function of _ in a refrigeration plant using Freon is to move moisture from all refrigeration system.制冷装置中，过滤枯燥器用来去除系统中的水分 A. filter B. fil

105、ter drier C. heat exchanger D. air cooler1240 The saturation temperature of the refrigerant must be _ that required in the evaporator refrigerated space.制冷剂的饱和温度应低于蒸发器所需要的温度。 A. above B. below C. equal to D. None of the above. 1236 A 1237 D 1238 D 1239 B 1240 B1241 After passing through the expansio

106、n valve the refrigerant should be in the state of _ 经过热力膨胀阀后，制冷剂应该是气、液混合物， A. vapor B. liquid C. solid D. None of the above is tree. 1242 The refrigerant flows through the evaporator, where it _ heat from the refrigerated space.当制冷剂经过蒸发器时，从被冷却空间吸收热量。 A. extracts B. releases C. gives no D. absorbs no

107、1243 In practice, the refrigerant flow after the evaporator is designed to ensure that the vapor leaving the evaporator is slightly _蒸发器出口的制冷剂蒸汽实际是处于过热状态。 A. saturated B. super-cooled C. wet D. superheated1244Which of the following will be desirable properties of refrigerant?1245 制冷剂应具有不爆炸、无腐蚀性，与润滑制

108、不起作用等性质1246 non-explosive; non- corrosive; that it does nt react with lubricants A. and B. and C. and D. and 1245 In the _ refrigeration compressor one end of the crank shaft extends through the crankcase house for connection, via a coupling or pulley, to an external drive motor. 在开启式制冷压缩机中，曲轴的一端通过联

109、轴节与外部的驱动马达相连。 A. open-type B. hermetic C. semi-hermetic D. all the above 1241 D 1242 A 1243 D 1244 A 1245 A1246 In a compression refrigeration plant the hot, high pressure refrigerant gas is cooled by the sea water and becomes liquid in the _ 在压缩式制冷装置中，高温高压的制冷剂气体被海水冷却而变成液体。 A. compressor B. condense

110、r C. throttle valve D. evaporator1247 What is the function of thermostatic expansion valve in a compression refrigeration system?在压缩式制冷装置中，热力膨胀阀用来控制过热度。 A. nonexistent B. for controlling pressure C. for controlling superheat D. for controlling the solenoid valve1248 In a vapor compression refrigerat

111、ion the evaporating pressure is maintained constant by the action of the _ , which removes vapor from the evaporator at the same rate at which it is formed.在压缩式制冷装置中，蒸发压力是由压缩机来维持。 A. evaporator B. compressor C. condenser D. none of the above1249 The device used for low-pressure control and high-pres

112、sure cutout on a compressor is called a _在制冷压缩机中，用来进行上下压控制的设备是压力控制器。 A. cutout B. controller switch C. pressure controller D. cutout switchWhich of the following may cause that the compressor cuts off on high pressure cutout in a refrigeration plant? faulty condensing; too few refrigerant; high disc

113、harge pres sure;冷凝故障、压缩机排出压力偏高，都会使高压控制器产生动作。而制冷剂缺乏会引低压控制器动作。 A. any of and B. any of ) and C. any of and I). any of and 1246 B 1247 C 1248 B 1249 C 1250 A1251 Which of the following may cause that excessively warm water leaves the condenser in a refrigeration plant? too little cooling water; too muc

114、h cooling water; too warm cooler water.冷却水缺乏、冷却水温过高，都会使冷凝器中冷却水出口温度偏高。 A. only B. any of and C. any of and D. any of and 1252 The presence of air in the condenser of a refrigeration system will _ the condensing pressure.制冷装置中，冷凝器中存在空气将会使冷凝压力升高。 A. increase B. reduce C. maintain constant D. None of th

115、e above is true.1253 Which of the following best describes overcharge of refrigerant? “制冷剂充注过多即“制冷剂太多。 A. Too much refrigerant. B. Too little refrigerant. C. Refrigerant is ran out. D. Running is over.What separate the high pressure side from the low pressure side in a refrigeration system.?制冷系统中，压缩

116、机和热力膨胀阀将系统分成高压侧和低压侧。 A. Condenser and thermal expansion valve. B. King and solenoid valves. C. Compressor and thermal expansion valve. D. Condenser and solenoid valve.1255 After fitting back in place the gear wheels, don t forget to _ them. 把齿轮装回原地后，不要忘了给它们加油。 A. fulfill B. eliminate C. grease D. be

117、nd 1251 C 1252 A 1253 A 1254 C 1255 C 1256 The defective places in the furnace _ with fire bricks. A. should be paved B. should be cleaned 炉膛损害处，应用火砖砌。炉膛损害处，应用火砖砌。 C. should be dismantled D. should be welded1257 The designed _ is 20 tons per day, but the fresh water generator can only distil 15 tons

118、 at present. 造水机设计容量是每天造水机设计容量是每天20t，但目前每天只能蒸馏，但目前每天只能蒸馏15t， A. displacement B. weight C. power D. capacity1258 The _ of the gravity disc is too big. It cause oil to flow through the water outlet. We changed the disc and no oil is found in the water outlet. 分油机比重环直径过大会引起分油机比重环直径过大会引起“跑油。跑油。 A. gravi

119、ty B. diameter C. circumference D. cylinderWater level controllers of the boiler must be kept operable to protect external steam-using plant from water _ danger. 锅炉的水位控制器应保持在可操作状态，以防产生锅炉的水位控制器应保持在可操作状态，以防产生“蒸汽携水危险。蒸汽携水危险。 A. carry off B. carry down C. carry on D. carry over1260 The shaft and spare p

120、arts _ should be well greased in order to avoid corrosion. A. in the store room B. in the cylinder 物料间的备件应上油以防腐蚀。物料间的备件应上油以防腐蚀。 C. in the scavenge air box D. in the water box1261 If a bilge pump failed to build up discharge pressure, you should check for _ 如果舱底水泵不能建立起足够的排出压力，应注意检查吸人滤器是否堵塞。如果舱底水泵不能建立

121、起足够的排出压力，应注意检查吸人滤器是否堵塞。A. excessive water in the bilges B. a clogged suction strainer C. oil in the bilges D. All of the above 1256 A 1257 D 1258 B 1259 D 1260 A 1261 B 1262Black smoke coming from a boiler can be caused by _1263 锅炉油温太低会使排气冒黑烟。1264 A. low water level B. high water level1265 C. excess

122、ively high fuel pressure D. low oil temperature12661263 Moisture should be kept out of an R-12 system because it tends to cause _ 1267制冷系统中存在水分，会引起自动控制器结冰、某些部件脆化以及污染滑油等。1268 A. icing of the automatic controls1269 B. embrittlement of some parts of the automatic controls1270 C. sludge in the lubricati

123、ng oil D. all of the above12711264 Air that may enter a refrigeration plant tends to collect in the _ 1272 进入到制冷装置的空气积聚在冷凝器的上半局部。1273 A. upper part of the receiver B. upper part of the condenser1274 C. down stream end of the cooling coil D. outlet end of the condenser12751265 Insufficient refrigeran

124、t in a refrigeration plant may result in _ 1276 制冷系统中冷剂缺乏，会导致压缩机吸人压力偏低。1277 A. high discharge pressure B. frosting of the crankcase1278 C. high temperature of the overboard water D. low suction pressure of compressor 1279 1262 D 1263 D 1264 B 1265 D1266 Which will cause the high pressre cutout to st

125、op the compressor in a R-22 system7冷凝器冷却水量缺乏，会引起冷凝压力偏高，压缩机高压控制器会产生动作。 A. Condenser leakage B. A shortage of liquid refrigerant C. Excessive frost on the evaporator D. Not enough condenser cooling water 1267 Black smoke coming from a boiler can be caused by _ 空气燃油比例不适宜(空气太少)，会使锅炉排气冒黑烟。 A. low water l

126、evel B. low oil pressure C. excessively high fuel pressure D. an improper air/fuel ratio 1268 A ruptured diaphragm in a thermostatic expansion valve will cause the valve to _ 如果热力膨胀阀的膜片破裂，膨胀阀将关闭 A. open B. close C. remain in its position D. flood the evaporator with refrigerant 1269 Which of the fol

127、lowing should be recorded in Oil Record Book Part I(machinery space operation ) ? 机器处所舱底水的非自动排放和自动排放，这两项操作都应记录到?油类记录簿?第 一局部(有关机器处所的操作) A. Non automatic discharge overboard of machinery space bilge water. B. Automatic discharge overboard of machinery space bilge water. C. A and B. D. Neither A nor B.

128、 1270 Oil Record Book Part I shall be provided to _ MARPOL公约规定，150总吨及以上的油轮和400总吨及以上的非油轮应配备?油类 记录簿?第一局部(有关机器处所的操作) A. every oil tanker B. every ship of 400 tons gross tonnage and above C. A and B D. Neither A nor B. 1266 D 1267 D 1268 B 1269 C 1270 B1271 The third engineer took the _ and checked the

129、tank table in the of- fice and recorded all relevant data, as well as calculated the bunkering.二管轮测量了吃水差、核查了舱位表，记录了相关数据并计算了加油量 A. water level B. sump level C. ballast tank level D. ships trim 1272 Dirty oil must be _ before being used again .脏油再次使用前必须经过净化 A. mixed with clean oil B. purified C. heate

130、d D. strained 1273 The emergency bilge suction or bilge injection valve is used to prevent _ of the ship. 应急舱底水吸口用来防止船舶淹水 A. proceeding B. overloading C. collision D. flooding 1274 All bilge suctions must be fitted with suitable _ , which in the machinery space would be mud boxes positioned at floor

131、 plate level for easy access.所有舱底水吸口一般都装设滤器(除应急舱底水吸口外) A. strangers B. relief valves C. emergency valves D. strainers1275 Which of the following is NOT on the list items to be recorded in Oil Record Book Part I (machinery space operation) ?“造水机的造水量该项不需要记录到?油类记录簿?第一局部(有关机器处所的操作) A. Accidental dischar

132、ge of oil. B. Disposal of oil residues. C. Quantity of water produced by F. W. G. D. Discharge of dirty ballast or cleaning water from fuel oil tanks. 1271 D 1272 B 1273 D 1274 D 1275 C1276 Which of the following influences the position of the interface between the liquid seal and the oil in a purif

133、ier?比重环影响分油机中油、水之间的界面 A. Height of the machine B. Temperature of the liquid seal C. Gravity disc D. Bowl diameter1277 For a L.O. purifier, If the back pressure of the oil outlet is too high, the interface between oil and water in the bowl will对于滑油分油机，滑油出口的背压过高，油、水之间的界面向别离简四周移动 A. be interrupted B. m

134、ove downwards C. move downwards D. retain original position1278 When in operation, it is unavoidable that a small amount of oil _ through leak- age, and in order to compensate for these leaks the system is connected to a feed pump.在运行过程中，不可防止地将会有一些油因为泄露而逃逸 A. escapes B. overheats C. expands D. accel

135、erates;1279 Coalescence is the breakdown of surface tension between oil droplets in an oil/water mixture, which causes them to join and _ in size.“聚合是指油水混合物中油滴之间外表张力的破裂，然后使油滴聚合，尺寸增大 A. expand B. extract C. increase D. decrease 1276 C 1277 C 1278 A 1279 C1280Which of the following chemicals will be u

136、sed where protection against caustic 1281 cracking is required in boiler treatment ?锅炉炉水处理中，使用硝酸钠来防止苛性脆化 A. Sodium hydroxide B. Sodium carbonate C. Sodium nitrate D. Sodium polyphosphate1281 The main steering gear must be able to steer the ship at maximum ahead service speed and be capable at this s

137、peed, and at the ships deepest service draught, of putting the rudder from 35 degrees on one side to 30 degrees on the other side within no _ 对于主操舵装置，应能使舵在不超过28s的时间内从一舷的35转到另一舷的30 A. more than 28 seconds B. more than 60 seconds C. less than 28 seconds D. less than 60 seconds1282 The auxiliary steeri

138、ng gear must be capable of being brought speedily into operation and be able to put the rudder over from 15 degrees on one side to 15 degrees on the other side in no more than _ with the ship at its deepest service draught and nmning ahead at the greater of one half of the maximum service speed or _

139、 对于辅操舵装置，应能使舵在不超过60s的时间内从一舷的15转到另一舷的5，而船舶的前进速度应不低于7kn A. 28 seconds/7 knots B. 28 seconds/14 knots C. 60 seconds/7 knots D. 60 seconds/14 knots 1280 C 1281 A 1282 C 1283 Special thrust devices are provided on ships to improve their _ at zero ship speed when the rudder is relatively ineffective.船舶侧推器

140、可提高船舶的机动性能 A. brake capabilities B. reversing capabilities C. maneuvering capabilities D. acceleration capabilities1284 The temperature_ a liquid changes its state from liquid to gas depends upon the liquid itself and upon the pressure _ it is subjected in the containing vessel.一种液体由液态变为气态时的温度取决于液体本

141、身，而且取决于它在容器中承受的压力。“在某个温度下应使用介词“at；“be subiected to意“承受，“tO放于定语从句引导词“which之前。 A. at which/to which B. from which/at which C. to which/from which D. in which/on which 1285 When making entries in the Oil Record Book, the date, operational code and item number shall be inserted in the appropriate column

142、 and the required particulars shall be recorded_ in the blank spaces.填写?油类记录簿?时，日期、作业代码和工程编号记录到相应的表格内，所要求的细节应按年月顺序记人到空栏中 A. periodically B. occasionally C. chronologically D. additionally 1286 _ shall be provided to every oil tanker of 150 tons gross tonnage and above to record relevant machinery sp

143、ace and cargo/ballast operations.MARPOL公约规定，150总吨及以上的油轮配备(油类记录簿?第一局部(有关机器处 所的操作)和第二局部(货油的操作) A. Oil Record Book Part I B. Oil Record Book Part II C. Oil Record Book Part I or Part II D. Oil Record Book Part I and Part II and its main content is 1283 C 1284 A 1285 C 1286 D1287 The core item in the Oi

144、l Record Book Part I is _ ?油类记录簿?第一局部(有关机器处所的操作)中，核心工程是C项，其内容是“残油 的处理 A. item A/BAHAST OR (21,EANING OF FUEL OIL TANKS B. item B/DISCHARGE OF DIRTY BAI JAST OR CI,EANING WATER FROM FUEL Oil. TANKS REFERRED TO UNDER SECTION (A) C. item C/DISPOSAL OF OIL RESIDUES (SLUDGE) D. item H/BUNKERING OF FUEL O

145、ILS1288 According to the international regulations concerning the prevention of pollution of sea areas from ships, the disposal into the sea of all plastics is _ MARPOL公约规定，一切塑料制品禁止倾倒人海 A. welcome B. admitted in some special sea areas C. prohibited D. acceptable1289 If you must enter a room or compa

146、rtment to combat the fire , keep an escape path _ 如果进人到一个舱室灭火，应保持一个脱险通道开启 A. open B. close C. opens D. closes1290 Upon the completion of required tests, a _ should be placed on each extinguish- er, showing the date and the person who completed the tests.灭火器试验后，应贴上标签，标注试验日期和试验人员 A. cap B. disc C. tag

147、 D. cover 1287 C 1288 C 1289 A 1290 C1291 _ , i.e. a steam cooler, may be rifled in the boiler system to control the superheated steam temperature.锅炉系统中，安装温度控制器来控制过热蒸汽的温度 A. An economizer B. An attemperator C. A water drum D. A down-comer tube1292 Air conditioning is the process of treating air to c

148、ontrol _ its temperature, humidity, cleanliness and distribution to meet the comfort requirements of the occupants of the conditioned space.空气调节是这样一种过程：同时调节空气温度、湿度、洁净度和进行分配，使其满足空调场所居住者的舒适要求 A. instantaneous B. instantaneously C. simultaneous D. simultaneously1293 One of the functions of ventilation

149、is to _ the humidity of spaces containing sources of moisture, or to _ the temperature of spaces not mechanically cooled such as the engine room.通风的一个功能是减少具有湿源之空间的湿度，或降温(如对于机舱) A. increase/reduce B. reduce/increase C. increase/increase D. reduce/reduce1294 _ is the control of temperature and humidit

150、y in a space together with the cir- culation, filtering and refreshing of the air.能对空间的温度、湿度进行控制，并能实现空气循环、过滤和补充新鲜空气的过程， 是“空气调节 A. Refrigeration B. Air conditioning C. Ventilation D. Heating 1291 B 1292 D 1293 D 1294 B1295 _ is the circulation and refreshing of the air in a space without necessarily

151、a change of temperature.能实现空气循环补充新鲜空气，但无需改变温度的过程，是“通风 A. Refrigeration B. Air conditioning C. Ventilation D. Heating1296 If liquid refrigerant accidentally comes in contact with the eyes, _ immediately.如果液体制冷剂进入到眼睛，应接受医疗。 A. n the eyes B. irritate the eyes C. wash the eyes with a heavy boric acid so

152、lution D. obtain medical help1297. Should a person be overcome due to lack of oxygen and high concentration of refrigerant, treat with _ 如果人员呼人高浓度的制冷剂而缺氧，应对其进行人工呼吸 A. fresh water B. flesh air C. salt water D. artificial respiration1298 Steering geam can be arranged with hydraulic control equitmnt kn

153、own as a _ , or with electrical control equipment:.舵机系统装有液压遥控马达或电力控制设备 A. telemeter B. telemanometer C. telemotor D. telemometer 1295 C 1296 D 1297 D 1298 C 1299Which of the following operations need NOT to be entered on the 1300 Oil Record Book Part I?1301 Routine discharge at sea of bilge water co

154、ntaining oil from the machinery spaces through strainers; Bunkering of fuel oil1302“机器处所含油舱底水的排放、“燃油的加装，这两项操作都应记录到?油类记录1303 薄?1304 A. only B. only C. both and D.neither and 13051300 Which of the following operations need NOT to be entered on the Oil Record Book Part I?1306 Disposal of oil residues;

155、Internal transfer of fuel oil1307“残油的处理应记录到?油类记录簿)；而“燃油的内部驳运不需要记录到?油类记1308 录簿?1309 A. only B. only C. both and D.neither and 13101301 Which of the following operations need to be entered on the Oil Record Book Part I?1311 Cleaning of fuel oil tanks; Internal transfer of fuel oil1312“燃油舱的清洁，应记录到?油类记录

156、簿)；而“燃油的内部驳运不需要记录到?油类1313 记录薄?1314 A. only B. only C. both and D.neither and 13151302 Which of the following operations need to be entered on the Oil Record Book Part I? Ballast .of fuel oil,tanks; Condition of oil discharge monitoring and control system.1316“燃油舱的压载，和“排油监视系统的状况都应记录到?油类记录簿)1317 A. on

157、ly B. only C. both and D.neither and1318 1299 D 1300 B 1301 A 1302 C 1303As the air passes through the charge air cooler, its temperature may be reduced and 1304 moisture condensed, with the condensate in danger of being carried into the engine. So a water separator should be mounted beneath the bot

158、tom part of the engine inlet manifold. A water separator is used in order to1305发动机进气总管底部装设分水器，是为了去除空气中的凝水1306 A. keep the air from being carried, into the engine1307 B. keep the moisture from being condensed1308 C. keep the danger from being carried into the engine1309 D. take away the condensate f

159、rom the air13101304 With reference to a two ram actuating mechanism, which one of the following statement is false?1311对于两撞杆的舵机装置，“十字头安装在舵柱上说法是错误的1312 A. The rams work inside cylinders.1313 B. The cylinders have glands sealing their open ends.1314 C. The rams are connected to a cross-head.1315 D. Th

160、e cross-head is mounted on the redder stock.13161305 With reference to an axial piston: pump, which one of the folio wing.statements is true ?1317对于轴向柱塞泵，圆柱形套筒必然具有奇数个孔，一般是7个或9个1318 A. The cylindrical barrel is coupled to the motor.1319 B. The cylindrical barrel has an odd number of bores.1320 C. The

161、 bores end in sockets.1321 D. The sockets fit in the swash plate.1322 1303 D 1304 D 1305 B1306 With reference to a radial piston pump, which one of the following statements is false ?对于径向柱塞泵，必然具有奇数个孔，一般是对于径向柱塞泵，必然具有奇数个孔，一般是7个或个或9个。因此个。因此D项错误项错误 A. Surrounding the fixed shaft is a hollow shaft. B. Th

162、is hollow shaft carries radial bores. C. Each bore is fitted with a weJl-lapped plunger. D. There are always even numbers of bores.1307 With reference to operating a four-mm steering gear system under emergency conditions, which one of the following statements is incorrect?对于应急情况下的四撞杆的舵机装置，应记录舵机的缺陷，

163、并通知驾驶台对于应急情况下的四撞杆的舵机装置，应记录舵机的缺陷，并通知驾驶台 A. Only one pump should be used any time. B. The ship speed shoed reduced to 70% of .the normal. C. Watch keeping of the steering gear,shd be increased. D. Limitations of the steering gear should be logged but the bridge need not be informed.1308 With, referenc

164、e to roles governing stccring gear, which one of the following roles is incorrect?有关舵机的规那么规定，客船上的辅助舵机必须是动力驱动的有关舵机的规那么规定，客船上的辅助舵机必须是动力驱动的 A. It is required that all ships are provided :with two independent steering gear systems that is one main and one auxiliary. B. The attxil gear could be power ope

165、rated in passenger ships. C. The auxiliary gear must be of adequate strength and sufficient to steer a ship at navigable speed. D. All moving parts of the steering gear must be guarded against any possible damage. 1306 D 1307 D 1308 B 1309 With reference to a mtm3r vane steering gear system, which o

166、ne of the following statements is true ?对于转口十式舵机系统，3个运动的叶片和3个固定的叶片组成6个压力腔室 A. The three moving vanes and the three fixed vanes form three, pressure chambers:. B. The three moving vanes and the three fixed vanes form six pressure chambers. C. The three moving vanes and the three fixed vanes form nine

167、 prmane chambers. D. The three moving vanes and the three fixed vanes form twelve chambers.1310 Large pipes or down-comers are fitted between the steam dram and _ to ensure good natural circulation of water.对于D型锅炉，在蒸汽筒和水筒之间安装的下行水管用来确保水的自然循环 A. fire-tubes B. furnaces C. water drums D. water wall1311

168、When a centrifuge is arranged to separate impurities and small amount of water from oil , it is known as a _ 1311离心式分油机设计用来别离杂质和少量水分，被称为分杂机 A. purifier B. separator C. filter D. clarifier1312 Topping wires fix the height of the derricks and _ to the deck may be used to prevent fore and aft movement.

169、吊杆式起货机中，顶索用来固定吊杆的高度，而牵索(稳索)用来防止吊杆前后晃动。 A. stays B. winches C. barrels D. brakes 1309 B 1310 C 1311 D 1312 A 1313 _ unit is mounted so as to raise and lower the cable from the spurling pipe, which is att he top and center of the c or cable locker. ,1313锚链轮装置用于从锚链管中升、降锚链。 A. The cable lifter B. hoisti

170、ng motor C. The topping wire D. The fife-raft1314 _ or dram is used for hauling in or letting out the wires or. which will fasten the ship to the shore1314绞缆卷筒用于收进或放出缆绳。. A. The winch motor B. The band brake C. The winch barrel D. The anchor capstan1315 Excessively warm water leaving condenser may b

171、e caused by _ 1315冷凝器中冷却水太少或温度太高，会引起冷凝器出口水温过高。 A. fouled tubes in shell and tube condenser B. too little or too warm condenser water C. air or non-condensable gas in system D. overcharge of refrigerant1316 Two rams of the hydraulic gear are linked at their outer ends to _ by a crosshead and: swivel

172、block.1316液压舵机的两个撞杆的外端通过十字头和转环与舵柄臂相连。 A. the piston rod B. the till arm C. the connecting rod D. the rudder1317 _ connected to the moving tiller will bring the floating lever pivot and the lever into the at right angles to the screw shaft axis.1317与舵柄相连的反响杆将浮杆带到与轴线成适宜角度的位置上。 A. A cut-off lever B. A

173、swivel lock C. A cross-head D. A driving gear 1313 A 1314 C 1315 B 1316 B 1317 A1318 _ system is arranged to ensure that water can be drawn from any tank or the sea and discharged to any other tank or the sea as required to trim the vessel.压载水系统用来确保能从任一个舱或海中吸人海水，也能将水排到任一舱或海中到达平衡船舶之目的 A. The domestic

174、 water B. Bilge water C. Oil transfer D. The ballast1319 Large pipes or _ are fitted between the steam and water drums to ensure good natural circulation of water.1319对于D型锅炉，在蒸汽筒和水筒之间安装的下行水管用来确保水的自然循环。 A. fire-tubes B. furnaces C. down-comers D. sootblowers 1320 The water level in the gauge glass wh

175、en a boiler is operating is _ when the boiler is shut down.1320锅炉运行时，水位表中水位比停炉时的要高。A.; lower than B, higher than C. below D. equal to 1321 Under rotary pumps are the gear, _ , cam-and-piston and screw types.1321齿轮泵、叶片泵、凸轮柱塞式泵和螺杆泵都属于旋转式泵。A. reciprocating B. diffuser C. turbine D. vane 1322 When the w

176、ater produced from most evaporator is supplied for drinking purpose, it must be treated to ensure it is biologically pure and _ 1322造水机产生的淡水用之于饮用，必须经过处理，使其纯洁并呈微碱性。 A. slightly acidic B. slightly alkaline C. no salty D. slightly bitter 1318 D 1319 C 1320 B 1321 D 1322 B 1323 _ provides the head or pr

177、essure to supply the domestic water where required.日用水系统中常采用压缩空气提供压头，确保供水。A. The compressed air B. The compressing air C. The transfer pump D. The head tank1324 may be fitted for operating the derrick topping lift (thewire which adjusts the derrick height).1324。吊杆式起货机中，卷绕端用来操作吊杆的顶索。A. A capstan B. A

178、 hold C. A warp end D. A mooring drum1325 The _ is used for hauling in or letting out the wires or ropes.1325，绞缆卷筒用于收进或放出缆绳。A. windlass B. anchor capstan C. turning gear D. winch barrel1326 Manually operated band brakes may be fitted and _ will have a brake arranged to fait-safe.1326起货机的驱动马达应具有制动装置，

179、用来故障平安保护。A. the drive pump B. the drive motor C. the warp end D. the purchase1327 In cargo crane, _ for lifting the load.1327克令吊中，提升装置用来提升货物。 A. a hoisting motor B. a luffing motor C. a mooring motor D. a slewing motor1328 The engine fuel oil system should be primed by using _ , and the system clear

180、ed of air by means of the various air vent cocks.1328备车时，发动机燃油系统应使用引液泵，使系统注油 A. the priming pump B. the transfer pump C. the hydraulic pump D. injector pump 1323 A 1324 C 1325D 1326 B 1327 A 1328 A1329 Domestic water pump is started automatically by _ which operates as the water level falls to a pre

181、determined level.日用水泵是由压力开关自动启动。A. a level controller B. a temperature switch C. a pressure switch D. a floating ball1330 _ is arranged for cleaning the lubricating oil in tim system and clean oil can be provided from a storage tank.1330离心式分油机用来清洁系统中的滑油。 A. A filter B. A centrifuge C. A distiller D.

182、 A generator1331 The pumps employed on board ship can be divided into two main categories, i. e. pumps and centrifugal pumps.1331泵可以分为两大类：容积式泵和离心泵。A. gear B. non-positive displacement C. positive displacement D. rotary1332 In a complete oil/water separator, more oil will separate out onto the unders

183、ide of these plates and travel outwards until it is free to rise into the oil collecting space. Whats the meaning of it in the sentence above?1332在油水别离器中，更多的油将会在捕集板上别离出来，并向外流动，直到能自由地上升到集油室。显然，句中“it指的是oil。A. a separator B. oil C. water D. an oil collecting space1333 Under centrifugal pumps are the vo

184、lute, diffuser, mixed-flow, axial flow and or regenerative types.1333离心式泵有：涡壳式、扩压式、混流式、轴流式和透平式等 A. reciprocating B. hydraulic C. turbine D. vane 1329 C 1330 B 1331 C 1332 B 1333 C 1334 In general, _ is suitable for delivering small quantities at high pressure.一般地说，往复泵适用于低排量、高压头的场合。 A. reciprocating

185、pump B. gear pump C. centrifugal pump D. vane pump1335 In a purifier, the interface between the liquid seal and the oil should be positioned as close as possible to _ 1335在分水机中，油水界面应尽可能地靠近别离筒的四周。 A. the outlet of oil B. the outlet of water C. the bowl periphery D. the center of bowl1336 Bottom blow

186、valves are installed on auxiliary water-tube boilers to _ 1336辅助水管锅炉安装下排污阀用于去除锅炉给水中脏物。 A. remove suspended and precipitated solids from the boiler water B. completely drain the boiler in an emergency situation C. prevent hardened scale deposits in the water dnnn. D. remove floating impurities from t

187、he oily water surface1337 Oil water separators are used to ensure that ships dont discharge oil when _ bilge water.1337“when pumping out bilge water是现在分词短语，作状语。 A. to pump off B. being pumped C. pumping out D. it pumping out1338 Additional heat extraction from the exhaust gases can be effected by ad

188、ding an _ section to the unit in plants.1338从废气中再吸收热量，这可以通过在装置中添加“经济器来实现 A. air cooler B. economizer C. injector D. air blower 1334 A 1335 C 1336 A 1337 C 1338 B1339 If a heavy sea strikes the redder, the shock is transmitted through _ to the rams, this cause a sudden increase in oil pressure in one

189、 of the cylinders.如果大浪打在舵叶上，冲击力会通过舵柄臂传递给撞杆。A. the control rod B. the hunting gear C. the floating ring D. the tiller ann1340 The control rod of a steering gear pump is attached at its outer end to _ 1340舵机泵的控制杆外端与追随机构相连。A. the hunting gear B. the rudder stock C. the redder controller D. the feedback

190、 unit1341 Where tanks are arranged for either oil or ballast _ must be fitted in the pipeline.1341对于多个油舱或水舱，管系中必须设置转换阀箱。A. a change-over chest B. a head tank C. a emergency bilge pump D. an air cooler 1342 he control spindle operates the slipper ring or _ of the variable de- livery pump, which contr

191、ols the suction and discharge of the oil.1342控制手柄用来操作变量泵的滑环或倾斜盘，以控制油的吸人和排出，A. servo-motor B. swash plate C. plunger D. cylinder 1343 _ is used for sensing the temperature of the room in the air condition system.1343。空调系统中使用温度控制器来感受空间的温度 A. An expansion valve B. An evaporator C. A thermostat D. A con

192、denser 1339 D 1340 A 1341 A 1342 B 1343 C 1344 According to the way the steering gear is operated, the steering gear may be divided into: hand- steering, _ and automatic steering.根据舵机操作方式的不同，可分为手动舵、随动舵和自动舵。A. hydraulic steering B. follow-up steering C. remote control steering D. air controlled steer

193、ing 1345 The various pumps and lines are _ to some extent so that each pump can act as an alternative for another.1345，各种泵和管路在某种程度上互通的，这样每个泵都可作另一泵的备用 A. interlocked B. interconnected C. interfered D. interacted 1346 _ _ are more suitable for large quantities at low pressure.离心泵适用于大排量，低压头场合。 A. Recip

194、rocating pumps B. Rotary pumps C. Centrifugal pumps D. Gear 1347 Gear pumps are _ type because they discharge a near constant amount of liquid regardless of pressure.1347齿轮泵是容积式泵。A. positive displacement B. non-positive displacement C. mixed-flow D. axial-flow 1344 B 1345 B 1346 C 1347 A 1348 Centri

195、fugal p are non-positive and a fairly _ unit.离心泵的排量不是恒定的，而且压头低。 A. low pressure B. low discharge C. low speed D. high pressure1349 In _ pump a closed discharge valve will not cause excessive pres-1349对于离心泵，排出阀关闭不会产生过高的压力。sure to build up. A. gear B. vane C. screw D. centrifugal1350 The emergency bil

196、ge suction or bilge _ is used to prevent flooding of the ship. 1350应急舱底水吸口用来防止船舶淹水。A. injection valve B. relief valve C. discharge valve D. inlet filter1351 Centrifugal pumps are popular because they are very simple in:construction, and produce smooth, constant, _ discharge.1351由于结构简单、排量平稳、连续而且无脉冲，离

197、心泵广为使用。 A. non-pulsating B. pulsating C. positive D. non-positive1352 _ is the breakdown of surface tension between oil droplets in an oil water mixture which causes them to join and increase in size.1352“聚合是指油水混合物中油滴之间外表张力的破裂，然后使油滴聚合，尺寸增大 A. Wear B. Contaminating C. Coalescence D. Coarse separating

198、 1348 A 1349 D 1350 A 1351 A 1352 C1353 The removal of _ from lubricating oil will reduce engine wear and possible breakdowns. 1353滑油中去除杂质有助于减少发动机磨损和可能发生的故障。A. contaminating water B. contaminated additives C. contaminated fuel D. contaminating impurities1354 _ is used for washing and drinking.1354日用

199、水系统用于盥洗和饮用了A. The ballast system B. The salt water system C. The bilge system D. The domestic system1355 The position of the interface between oil and water within the centrifuge is achieved by the use of1355离心式分油机中，油水之回的界面是通过比重环来实现的。 A. gravity disc B. centrifugal bowl C. a stack of discs D. main s

200、ealing ring1356 If a heavy sea strikes the _ , the shock is transmitted through the tiller to the rains. 1356如果大浪打在舵叶上，冲击叻会通过舵柄臂传递给撞杆。 A. propeller B. rudder C. bow thruster D. stabiliser 1353 D 1354 D 1355 A 1356 B1357 No specific period is given for the renewal of the lubricating oil filter elemen

201、t as this should be done _ a figure of 0.7 bars is shown on the gauge.bar时应更换。A. whatever B. whenever C. wherever D. whoever1358 To start the ejection process the oil feed to the centrifuge is first shut off and the oil remaining in the bowl removed by admitting _ 1358为了开始喷射冲洗过程，首先应切断向分油机供汕，残留在别离韵内的

202、油通过注入冲洗水去除。A. flashing water B. operating oil C. flushing water D. sealing water1359 The interface between the liquid seal (water) and the oil should be positioned _ possible to the bowl periphery.1359在分水机中，油水界面应尽可能地靠近别离筒的四周。A. as far as B. as soon as C. as close as D. as closer as1360 What is used

203、to purify water and foreign matters from the fuel oil in the following?1360土扑由机用来别离燃油中的水分和杂质。 A. Compressor B. Separator C. Evaporator D. Fuel pump1361 They understand the _ of automatic sludge discharging of the purifier. But they are not good in practice.1361他们明白分油机自动排污原理 A. principle B. principal

204、 C. theory D. ease 1357 B 1358 C 1359 C 1360 B 1361 A1362 Here some oil in the oily water separator, as a result of its lower _ will separate and rise into the oil collection space.在油水别离器中，一些油由于比重小，会别离出来，并上升到集油室。 A. temperature B. viscosity C. density D. velocity1363 The diameter of the gravity disc

205、 is too big, It causes oil to flow through the water outlet. We changed the disc and no _ is found in the water outlet.1363比重环直径太大引起分油机跑油。更换比重环后，发现山水口没有油了。A. water B. oil C. scale D. ridge1364 Sealing in pump shaft is achieved by means of the _ 1364。泵轴的密封是通过填料来实现的。A. gasket B. packing C. washer D. s

206、pring1365 Centrifugal pumps, however, can be designed with a number of impellers _ to attain a large amount of liquid.1365离心泵通过并联的方法，可实现更大的排量。 A. in series B. in parallel C. assembled D. together 1362 C 1363 B 1364 B 1365 B1366 All bilge suction must be fitted the suitable _ , which in the machinery

207、 spaced be:mud boxes positioned at floor- plate level for easy access.所有舱底水吸口应装设滤器。A. strainers B. valves C. elements D. separators 1367 Impurities from the boiler water surface :can be removed through the1367锅炉水面的杂质可通过上排污阀排除。A. safety valve B. blow clown valve C. scum valve D. feed check valve 1368

208、 The exhaust boilers are used to recover some of _ carried in the exhaust gas from the main engine.1368废气锅炉用来回收主机废气中所携带的热量。A. water B. oil C. heat D. steam 1369 The defective place in the furnace should be _ with fire bricks.1369炉膛损害处应用火砖砌。A. paved B. cleaned C. welded D. dismantled 1370 The safety

209、valves are mounted in pairs to _ the boiler against overpressure.1370锅炉平安阀用来防止锅炉超压 A. use B. release C.protect D. effect 1366 A 1367 C 1368 C 1369 A 1370 C1371 The safety valve should be _ in the presence of C/E and Surveyor.锅炉平安阀应在轮机长和验船师在场的情况下铅封。 A. tightened up B. sealed up C. opened up D. unscre

210、wed1372 Between the steam drum and the smaller water drum below , large numbers of smaller diameter _ tubes are fired.1372对于D型锅炉，在蒸汽筒与水筒之间，安装了大量小直径的产汽管。 A. fire B. water wall C. generating D. down comer1373 A _ boiler is an auxiliary boiler some included in a steamship s installation for supplying s

211、team to auxiliaries in port.辅锅炉，即是辅助性锅炉，有时电包括在蒸汽机船装置中，用于在港口时向辅助机械 提供蒸汽。 A. monkey B. donkey C. waste heat D. main1374 Water evaporates or steam condenses at the saturation temperature, which depends upon the pressure, the higher the preare _ the saturation temperature.1374水在饱和温度下蒸发，水蒸汽在饱和温度下冷凝。饱和温度取

212、决于饱和压力， 越高，饱和温度也越高。A. the more B. the higher C. the lower D. the highest1375 The soot blowers are operating in the oil fuel boiler the air/fuel ratio must _ throughout the action, and blowers-greased :after use.1375锅炉吹灰器运行时，空气燃油的比例应逐渐提高 A. be increased B. be decreased C. remain constant D. either be

213、 increased or remain constant 1371 B 1372 C 1373 B 1374 B 1375 A1376 At normal sea going , we use _ instead of donkey boiler.在海上航行时，使用废气锅炉来代替辅助锅炉。A. a heater B. a pre-heater C. an exhaust gas boiler D. the coal burning boder1377 The internal part of ,boiler should be cleaned by yard if found. _ 1377

214、锅炉内侧发现水垢，应进行清洁。 A. scaled B. worn C. deformed D. rusted1378 The oil _ in the discharging water from oil water separator exceeds 15 PPM without alarm, because the coil was burnt out.1378油水别离器出水口油分浓度超过ppm，但没有报警因为线圈烧毁了。A. filter B. hole C. pollution D. content1379 The remaining oil/water mixture now fl

215、ows down into the fine separating compartment and moves slowly between the _ in the Turbulo separator.1379。剩下的油水混合物向下流到细别离室，并在捕集阪之间慢慢流动、A. catch plates B. swash plates C. cover plates D. bedplates1380 Grease the roller bearings with H.P. gun . In the sentence H. P. means1380。使用高压牛枪给滚株轴承加牛油： A. horse

216、 power B. high pressure compressor C. hand pump D. high pressure 1376 C 1377 A 1378 D 1379 A 1380 D1381Anchor _ are used in some. installations where the cable lifter rotates about a vertical axis. 1382在一些装置中，使用锚绞盘，锚链轮绕立轴旋转。1383A.windlasses B.drums C.capstans D.warp ends13841382 Prior to running the

217、 hydraulic pump, examine the system carefully and ensure the lever of Control valves is in _ position.13851382运行液压泵之前，应仔细检查系统，确保控制阀杆处在中央位置?1386 A. neutral B. end C. opening D. closure13871383 Anchor capstans are used in some installation where the cable lifter rotates about a _ 13881383在一些装置中，使用锚绞盘，

218、锚链轮绕立轴旋转。1389A. horizontal axis B. crankshaft C. vertical axis D. camshaft13901384 If a heavy sea strikes the rudder, the shock is transmitted through the tiller to _ 13911384如果大浪打在舵叶上，冲击力会通过舵柄臂传递给撞杆。1392 A. the tiller arms B. the swivel blocks C. hunting gears D. the rams13931385 The hand steering

219、is a method by which the motion of the rudder is controlled with _ 13941385手动舵，即舵的运动是由手动驱动的舵轮来控制。1395 A. a motor-driven steering wheel B. a pneumatic steering wheel1396 C. a hand-driven steering wheel D. an electric steering wheel1397 1381 C 1382 A 1383 C 1384 D 1385 C1386 These include deck machine

220、ry such s mooring equipment, cranes and _ 系缆设备、起锚设备、克令吊、舱盖板等都属于甲扳机械。 A. boilers B. bow thrusters C. stabilizers. D. hatch covers1387 A warp end may be fitted for operating the derrick topping wire which adjusts the derrick _ 1387吊杆式起货机中，卷绕端用来操作吊杆的顶索。A. length B. slack C. height D. rotation direction

221、 1388 In a general cargo crane, three principal movements are _ ; _ ; _.1388对于普通克令吊，三种根本运动是：提升、变幅和回转。 A. hoisting/luffing/slewing B. lifting/raising/lowering C. rotating/raising/handling D. hosting/lowering/moving1389 For occasional heavy loads, two cranes can be arranged to work together The operat

222、ing for deck crane motors may be hydraulic electric.1389克令吊马达的驱动介质可以采用液压油或电力、 A. principle B. medium C. instruction D. voltage 1386 D 1387 C 1388 A 1389 B1390 In the cargo winch, spur reduction gearing transfers the motor drive to _ 在货物绞车中，减速齿轮将马达的驱动力传递给卷筒轴。 A. the toping light B. the board brake C.

223、 the fail-safe D. the barrel shaft1391 The inner part of the condenser should be cleaned with _1391。冷凝器的内侧应用化学剂清洁。A. gas oil B. diesel oil C. chemical compound D. Freon-121392 The shutter of the evaporator was blocked with _ it means there was too much evaporation.1392蒸发器的格栅被冰堵塞了，说明蒸发过度 A. ice B. wo

224、oden board C. iron plate D. cotton waste1393 The quantity of cooled air delivered by an air conditioning unit should _ the sum of the quantity of air re- circulated to the unit and the quantity mechanically exhausted.空调装置输送的冷气量应该与再循环到装置的空气量和机械排出的空气量之和平衡。A. balance B. not balance C. be more than D. b

225、e less than1394 Freon 12 which is used to produce intense cold is normally a _ when at atmospheric pressure and temperature.1394制冷剂R12在大气温度和压力下是一种气体。 A. liquid B. gas C. solid D. water only 1390 D 1391 C 1392 A 1393 A 1394 B1395 As the refrigerant passes through thevalve orifice, its pressure is red

226、uced and part of the refrigerant turns into1395当制冷剂经过节流阀时，压力下降，局部制冷剂变成蒸汽。A. liquid B. oily mixture C. emulsion D. vapor1396 Because the expansion valve is just _ way open, the refrigerant is under low pressure, in the evaporator. 1396因为膨胀阀只有少许翻开，制冷剂在蒸发器中处于低压。 A. little B. few C. a little D. a fewThe

227、 refrigerating agent can _ at low temperature in the evaporator.1397、制冷剂能在蒸发器中在低温下蒸发。 A. expand B. evaporate C. condense D. distil1398 Faulty operation of any system is indicated by very definite1398任何系统的故障运行，都会以某种征兆显示。A. symptoms B. samples C. traces D. tracks1399 The boiling and condensation point

228、s of a refrigerant depend on the _ exerted up on it. 1399制冷剂的蒸发温度和冷凝温度取决于压力(蒸发压力和冷凝压力)。A. temperature B. pressure C. velocity D. heat In the condenser, the hot, hi pressure refrigerant gas is cooled by the sea water and becomes _ 1400在冷凝器中，高温高压的制冷剂气体被海水冷却而变成液体 A. fresh water B. vapor C. mixture D. l

229、iquid 1395 D 1396 C 1397 B 1398 A 1399 B 1400 D1401 We use _ to distill fresh water from seawater.使用造水机，从海水中蒸馏淡水。A. engine B. sea water pump C. cylinder cooler D. fresh water generator1402 Because of the reduced _ in the vacuum boiling evaporator, some of the sea water boils as it flows through the

230、tubes.1402由于真空蒸发式造水机的压力较低，海水经过管子时便蒸发了。 32A. temperature B. water level C. pressure D. rate of flow1403 The fresh water generator produces fresh water _1403造水机通过海水的蒸发来产生淡水。 A. by cooling sea water B. by heating sea water C. by evaporation of sea water D. by purifying sea water1404 Clean oil is achiev

231、ed in a clarifier bowl where the impurities and water collect at the bowl _ 1404在分油机中，杂质和水都积聚在别离筒的四周。 A. bottom B. top C.center D.periphery 1405 The designed capacity is 25 tons a day, :but the fresh water generator can only _ 22 tons at present.1405造水机的设计容量是每天25t，但目前每天只能蒸馏22 A. consume B. distill C

232、. run D. operate 1401 D 1402 C 1403 C 1404 D 1405 B 1406 In the process of _ , liquid changes into gas.在蒸发过程中，液体变成气体。 A. evaporation B. frosting C. condensing D. compressing1407 More than one stage of evaporation can take place by admitting the sea water into chambers with progressively _ pressure i

233、n th flash evaporator.1407在闪发式造水机中，通过让海水进入到压力渐低(真空度渐高)的几个腔室中，实现多级蒸发。 A. lower B. higher C. the lower D. the higher1408 You must take good care of the drainage cock of the air control system. Because _ leads scale formed which might malfunctions the pilot control valve and other instruments.1408对于空气控

234、制系统的放残旋塞应仔细照料，因为水分会引起水垢，从而使控制导阀和其他仪器失灵。A. the temperature B. the rust C. the pressure D. the humidity1409 Keep compartment _ as the gm given off can be dangerous.1409应保持舱室良好通风，因为释放的气体很危险。 A. well ventilated B. well clean C. in good order D. more room1410 Gear pumps are _ because they discharge a nea

235、r constant amount of liquid regardless of pressure.1410齿轮泵是容积式泵 A. negative displacement type B. turbine type C. positive displacement type D. mixed-flow type 1406 A 1407 A 1408 D !409 A 1410 C1411 The boiler is fired _ the demand for steam exceeds that available from exhaust gas heating当蒸汽的需求量超过废气加

236、热产生的蒸汽量时，锅炉便开始烧油运行。A. whenever B. however C. wherever D. whether1412 An oil water monitor is required in order to measure _ .1412油分浓度监测器用来监测水中的含油浓度。A. the oil content in water B. the water content in fuel oil C. the water level in bilge well D. the oil level in bilge well1413 Oil Record Book Part I

237、shall be provided to every oil tanker of 150 tons gross tonnage and above and every ship of 400 tons gross tonnage and above, _ oil tankers, to record relevant machinery space operations.1413MARIL公约规定，150总吨及以上的油轮和400总吨及以上的非油轮应配备?油类记录簿?第一局部(有关机器处所的操作)。otherthan=except。A. as well as B. as long as C. r

238、ather than D. other than1414 The bilge main is arranged to drain any watertight compartment _ ballast, oil or water tanks and to discharge the contents overboard1414舱底水总管设计用来排放除了压载舱、燃油舱和水舱之外的任何水密空间的污水到舷外。otherthan=except。A. more than B. other than C. in addition to D. except for1415 If oil density w

239、ere greater than waters, the oil separator _ 1415如果油的密度比水大，分油机便不能工作 A. did work B. would work well C. didnt work D. wouldn t work 1411 A 1412 A 1413 D 1414 B 1415 D 1416 Oil water separators are used to ensure that ships dont discharge oil when pumping out _ 油水别离器用来确保船舶排放舱底水时不排油。A. ballast water B.

240、boiler water C. bilge water D. sewage waterA hydraulic machine is one that uses _ to do work.417液压设备是使用液体做功的设备。A. liquid B. steam C. gas D. electricity1418 In a vacuum distillation system, the case is the higher the pressure, _ 1418在真空蒸馏系统中，压力越高，饱和温度也就越高。A. the saturation temperature is higher B. th

241、e higher the saturation temperature C. the higher is the :saturation temperature D. the saturation temperature is more high1419 Because of the reduced _ in the distillation system, some of the sea water boils as it flows through the t of the evaporator.1419由于真空蒸发式造水机的压力较低，海水经过管子时便蒸发了。 A. pressure B.

242、 temperature C. density D. volume 1416 C 1417 A 1418 B 1419 A 1420 In extreme weather conditions, either hot or cold, control of the air conditioning plant presents _ difficulties.在tR端气温(太低或太高)条件下，空调装置的控制几乎不会产生困难。A. few B. little C. a little D. less1421 Most air conditioning units have _ for adjusti

243、ng the ratio of recirculated fresh air. Care must be taken not to reduce the fresh air so that stuffiness or smells arise.1421绝大多数空调装置都有风门，用于调节再循环新鲜空气量。A. catch plates B. dampers C. regulating valves D. fans1422 For the intermediate condition, thefts must be correctly set _ 1422对于中等的气温条件，温度控制器应使用“反复

244、试验法来设定。 A. by trial and error B. by and large C. automatically D. very easily1423 lne coder as the liquid becomes, _ .1423液体越冷，蒸发将越侵； A. the faster it will evaporate B. the slower it will condense C. the slower it will evaporate D. the faster it will flow1424 Where an excessive level of contaminatio

245、n is detected an alarm is sounded and diverting valves are operated. The discharging liquid is then passed to _ 1424当油分浓度监测器监测到油分超标时，会发出报警，相关阀门动作，液体排到污水舱。 A. overboard B. a bilge well C. a slop tank D. a hot well 1420 A 1421 B 1422 A 1423 C 1424 C 1425 When a boiler is operating, the water level in

246、the gauge glass reads _ when the boiler is shut down.锅炉运行时，水位表中水位比停炉时的要高。A. lower than B. higher than C. as much as D. the same as 1426 Strainers and fine filters should be cleaned at intervals, _ prevent dirt from getting under a fuel injection pump valve.1426粗细滤器应定期清洗，以防脏物积聚在燃油喷射泵之下 A. in order th

247、at B. so as to C. so that D. in addition to 1427 The fine filters will be arranged _ one can be cleaned while the other is细滤器应这样布置：一台工作时，另一台可以清洁。operating. A. in order to B. because of C. so that D. so as to 1428 In _ , hot diesel engine jacket water passes over the stack and heats the sea water pas

248、sing through the tubes.1428当真空蒸发式造水机工作时，气缸冷却水经过热交换器(海水加热器)，给管内流动的海水加温 A. a flash generator B. a flash evaporator C. a vacuum boiling evaporator D. a boiler 1425 B 1426 B 1427 C 1428 C1429 In an oil cooler circulated by sea water, the oil is at a larger pressure the result being that any leak in the

249、cooler will mean a loss of _在海水循环的油冷器中，油压比水压高，结果是油冷器发生泄漏时，滑油损失了。A. oil B. sea water C. refrigerant D. fresh water 1430 Sediment collects in a tubular purifier _1430在分水机中，沉淀物积聚在别离筒的边上。A. on top cover B. on sides of bowl C. in drain line on the discs D. on the discs 1431 The _ discharge a nearly const

250、ant amount of liquid regardless of pressure.1431不管压力如何，容积式泵总是排出几乎恒定的流量。A. mixed-flow pump B. axial-flow pump C. centrifugal pump D. displacement pump 1432 The gear, screw, and vane pumps are all classified as1432齿轮泵、螺杆泵和叶片泵都归类于容积式泵 A. variable stroke pumps B. multistage pumps C. positive displacemen

251、t pumps D. triple-ported pumps 1429 A 1430 B 1431 D 1432 C 1433 Which of the following are components of a mechanical seal? stationary ring; rotational ring: packing; spring.静环、转环和弹簧都是机械密封的部件。A. , and B. , and C. , and D. None of the above.1434 he pressure head of a water pump is given in the unit o

252、f _ 1434水泵的压头单位可用m20。A. kg B. MPa C. mH20 D. None of the above. 1435 A vane pump belongs to _ according to its working principle.1435根据工作原理，叶片泵属于容积式泵。A. reciprocating pumps B. positive displacement pumps C. centrifugal pumps D. centrifugal pump1436 Attempts are made to eliminate axial thrust in cent

253、rifugal pump by _ 1436消除离心泵的轴向力，可使用具有平衡孔的叶轮，也可使用对称叶轮 A. providing the impeller with counterbalancing holes B. the use of symmetrical impeller C. neither A nor B D. A and B 1433 B 1434 C 1435 B 1436 D 1437 Generating tubes in waste heat boilers are finned to _ 废热锅炉的产汽管带翅片，目的是为了增大传热的速度。A. reduce gas f

254、low turbulence B. prevent est gas corrosion C. increase the rate of combustion D. increase the rate of heat transfer1438 The concentration of total dissolved solids in the water of an auxiliary boiler can increase as a result of1438辅助锅炉给水的总溶解固体含量会因海水污染而提高。A. seawater contamination B. frequent surfac

255、e blows C. dissolved oxygen deaeration D. frequent bottom blows1439 Air chambers are usually fitted to reciprocating in order to _ 1439往复泵中的空气室用来保持流量稳定。A. increase discharge pressure B. increase suction vacuum C. develop pulsation flow D. keep a steady rate of flow1440 The water in an auxiliary boil

256、er should be,tested for chloride content to determine _ 1440对辅助锅炉的给水进行含氯量的化验，用来判断是否被海水污染 A. total dissolved solids B. salt contamination C. water hardness D. chlorine contamination 1437D 1438 A 1439 D 1400 B1441 A positive displacement pump is that where the volume of the pump chamber is alternately

257、 _ to draw the liquid in and then _ to force the liquid out.对于容积式泵，泵腔室体积增大时吸人液体，体积减少时那么排出液体。 A. increased/decreased B. decreased/increased C. decreased / decreased D. increased/increased1442 Which of the following pumps are self-priming, and can deal with liquid form a level below the pump? reciproc

258、ating; rotary; centrifugal.1442往复泵和旋涡泵都具有干吸能力。A. only B. and C. and D. and 1445 Which of the following pumps are serf-priming, and can deal with liquid from a level below the pump?, reciprocating; vane gear.1443往复泵、叶片泵和齿轮泵都具有干吸能力。A. only B. and C. and D. and 1444 A pump is said to have negative suct

259、ion head when the pump is located _ 1444当泵位于供液管之上时，泵具有“负压头。 A. between the suction and discharge B. below the lid supply C. above the liquid supply D. any of the above 1441 A 1442 B 1443 C 1444 C1445 If a bilge pump failed to build up discharge,pressure, you should check for _ . 如果舱底水泵不能建立起排出压力，应检查滤

260、器是否堵塞。A. excessive water in the bilges B. a clogged suction straine C. oil in the bilges D. a closed skin valveThe advantage of a centrifugal pump as compared with a reciprocating pump is that _ 1446离心泵与往复泵相比具有以下优点：排量连续；无内部阀件；如果排出阀关闭，不会产生过高的压力。 A. discharge is continuous B. it has no internal valves

261、 C. upon accidental closing of discharge valve, excessive pressure will not build up D. all of the above are true1447 Which of the following pumps belongs to centrifugal pump?1447扩压泵属于离心式泵。 A. Reciprocating pump. B. Screw pump. C. Diffuser pump. D. Water-ring pump.1448 While flowing through the volu

262、te in a centrifugal, part of the _ energy of the liquid is converted to _ energy.1448当液体经过离心泵的涡壳时，局部动能转换成压力能 A. kinetic/pressure B. kinetic/essential C. pressure/kinetic D. pressure/height 1445 B 1446 D 1447 C 1448 A1449 When there is a flame failure in an automatically fired auxiliary boiler, the _

263、 自动锅炉因故障熄火，应切断燃油供给。A. air supply is shut off B. fuel supply is shut off C. water supply is shut off D. safety valve lifts1450 Fins are installed on the generating tube surfaces in waste heat boilers to _ 1450废热锅炉的产汽管带翅片，目的是为了增大传热的速度。A. prevent soot fires in the exhaust system B. prevent exhaust gas

264、erosion of the tubes C. increase the velocity of exhaust gas flow D. increase the rate of heat transfer1451 Excessive vibration of an automatically fired auxiliary boiler can be caused by _1451自动锅炉的燃烧脉冲会引起锅炉振动过大。 A. air or water in the furnace B. combustion pulses C. fuel oil pump failure D. flame f

265、ailure 1449 B 1450 D 1451 B 1452 If the feed pump for an auxiliary boiler fails to deliver the feed water to the boiler, the cause may be _ 辅助锅炉给水温度过高，给水泵会失去吸人压头。 A. high steam pressure in the boiler B. abnormally high feed water temperature C. abnormally high boiler water temperature D. steam deman

266、d exceeding feed pump capacity1453 Black smoke coming from a boiler can be caused by _ 1453。空气燃油比例不适宜(空气太少)，会使锅炉排气冒黑烟。A. low water level B. low oil pressure C. excessively high fuel pressure D. an improper air/fuel ratio1454 Proper combustion in a boiler would be indicated by _ 1454锅炉正常燃烧火焰应该是金黄色。A.

267、 yellowish flame B. golden yellow flame C. white flame D. brilliant white flame1455 The feed water to the boiler will comprise1455 锅炉的给水包括凝水和少量的补偿水 A. condensate B. a small amount of make-up feed C. A and B D. None of the above. 1452 B 1453 D 1454 B 1455 C1456 The furnace of a oil-fired boiler shoul

268、d be _ before the operating burner is lit. 锅炉点火前，应进行扫气。“purge意“驱气；而“clearofair意“去除空气。 A. filled with water B. purged C. cleared of air D. none of the above1457 Too much air in the furnace of an oil-fired boiler would be indicated by1457对于烧油锅炉，空气过多，火焰呈亮白色。 A. yellowish flame B. golden yellow flame C.

269、 white flame D. brilliant white flame1458 A donkey boiler is _ 1458辅锅炉是辅助性锅炉。A. one to supply steam to the main propulsion turbine B. an auxiliary boiler C. A and B D. neither A nor B 1459 A feed pump for an auxiliary boiler might lose suction if the _ 1459辅助锅炉给水温度过高，给水泵会失去吸人压头 A. boiler water level

270、 is low B. feed water is too hot C. boiler steam demand is low D. feed water is too cold 1456 B 1457 D 1458 B 1459 B1460 The water level in a steaming boiler will always _ 辅助锅炉的水位将随蒸汽需求量的变化而变化。A. vary as the steam demand changes B. remain constant as long as the feed pump operates C. fall when the s

271、team pressure is decreased D. rise when the steam pressure is increased1461 Which of the following conditions could cause the feed pump for an auxiliary boiler to lose suction?1461辅助锅炉给水温度过高，给水泵会失去吸人压头。 A. Increased suction head pressure B. Decreased feedwater temperature C. Pump recirculating line

272、being open too much D. Excessive feedwater temperature1462 If at a normal steaming condition and water goes out of sight in gauge glasses the action you should take is: secure oil to fires; increase feed pump pressure.1462自动辅助锅炉的燃油供给系统在发生锅炉水位异常低的情况下，将自动切断燃油供给。 A. B. and C. D. neither nor 1460 A 1461

273、 D 1462 A 1463 Foaming in the steam drum may be caused by _ in a boiler.蒸汽需求量过大会引起蒸汽筒产生汽泡。 A. oxygen in the water B. poor boiler design C. density too high D. excessive steam demand1464 The water in an auxiliary boiler should be tested daily for _ 对辅助锅炉的给水，应每天化验氯含量。 A. dissolved oxygen B. chlorides

274、C. sludge D. dissolved nitrogen1465 In a _ boiler the hot gases from the furnace pass through the tubes while the water is on the outside.1465对于火管锅炉，高温气体在管子内流动，而水在管子外流动。A. water-tube B. fire-tube C. exhaust gas D. None of the above.1466 _ should be tested and adjusted when the boiler survey is carri

275、ed out.1466当进行锅炉检验时，应对锅炉平安阀作试验和调整 A. The boiler oil tank B. The steam pipe C. The fire side D. The safety valves 1463 D 1464 B 1465 B 1466 D1467 In readying an auxiliary water-tube boiler for a routine hydrostatic test, which of the following procedures should be undertaken prior to filling the boil

276、er with fresh water.?准备对辅助水管锅炉进行周期性的水压试验，在注人淡水之前，首先应翻开锅炉的放气阀。 A. The safety valve escape piping should be disconnected from the valve body and a blank inserted. B. The boiler vent valves should be opened. C. All hand-hole/manhole covers should be tightened up as much as possible to preclude any leak

277、s. D. All of the above. 1468 A dazzling white burner flame in the boiler furnace indicates _ 1468对于烧油锅炉，空气过多，火焰呈亮白色 A. proper combustion B. water in the fuel C. excess air D. cold fuel oil 1467 B 1468 C1469 The fuel supply system to an automatic auxiliary boiler, will be automatically shutdown if th

278、e boiler _ 自动辅助锅炉的燃油供给系统在发生锅炉水位异常低的情况下，将自动切断燃汕供给。A. salinity is abnormally high B. steam demand is too high C. water level is abnormally low D. feedwater flow is low1470 The correct pH value of boiler water is achieved by continuous addition of a suitable _ to the feed.1470，锅炉给水适宜的P值是通过参加碱性物质来实现的。 A

279、. acid B. alkali C. salt D. None of the above1471 Black smoke coming from a boiler can be caused by _ 1471汕温低会引起锅炉冒黑烟。A. low water level B. high water level C. excessively high fuel pressure D. low oil temperature1472 _ will be used to blow away soot and the combustion products from the tube surface

280、.1472吹灰器用来吹除管子外表的燃烧产物。 A. The blow down valve B. The scum valve C. The air release cock D. Soot-blower 1469 C 1470 B 1471 D 1472 D 1473 After a normal, or safety shutdown, automatic combustion control systems for an auxiliary boiler are designed to prevent the immediate re-firing of a burner in orde

281、r for the _ 辅助锅炉的自动燃烧控制系统能防止锅炉在正常熄火后迅速再次点火，其目的是为了使炉膛再次扫气。A. furnace to be re-purged B. electric charge to buildup in the igniter C. fuel pump to restart D. drum level to stabilize1474 Improper maintenance of an automatic auxiliary boiler oil burner could result in _ 1474自动锅炉的燃烧器保养不善，会引起锅炉效率下降。A. fue

282、l pump failure B. fan motor failure C. increased feed-water consumption D. decreased boiler efficiency1475 If the fire goes out in an automatically fired auxiliary boiler and the burner continues to sup ply fuel, there is a potential danger of _ 1475、如果自动锅炉熄火了，而燃烧器继续供油，那么有炉膛爆炸的潜在危险 A. overpressure a

283、nd dry firing B. a severe furnace explosion C. spalling damage to the brickwork D. heat damage to the atomize 1473 A 1474 D 1475 B1476 Prior to lighting off a cold automatically fired auxiliary boiler, you should _ 对处于冷态的自动点火锅炉点火前，应检查并调节水位。 A. check and regulate the water level B. close the air cock

284、 once fires are lit C. blowdown the gage glass D. crack the steam stop to assure protective steam flow1477 Which of the following items is necessary for all waste heat boiler installations, regardless of design or manufacturer?1477对于所有废热锅炉装置，必须具有蒸发控制设备。 A. Control of evaporation. B. A separate means

285、 to prevent feed-water contamination. C. Power circulating pump. D. Super-heater.1478 For proper operation, auxiliary boiler feed water must have which of the following characteristics?1478辅助锅炉的给水应具有适当的碱度以确保锅炉正常运行。 A. High oxygen concentration. B. Low pH. C. Proper alkalinity. D. All of the above. 1

286、476 A 1477 A 1478 C1479 When a waste heat boiler is installed in the exhaust of a main propulsion diesel engine, the exhaust gas bypass would be used _ 1479主推进柴油机排气总管后设置废气锅炉，在低负荷时应使用废气旁通以防锅炉产：生腐蚀。 A. at high loads to prevent overheating B. at low loads to prevent corrosion in the boiler C. during pe

287、riods of high steam demand D. when the turbocharger is in operation1480 When a hydraulic vane pump is working, which of the following is in contact with the vanes? the rotor; the internal surface of the housing; the external surface of the housing.1480对于液压叶片泵，工作时，转子和泵壳内侧与叶片接触。 A. only B. only C. and

288、 D. and 1481 Thermostatic expansion valve are _ 1481在工作过程中，热力膨胀阀是根据负荷来实现制冷剂节流的。 A. either all the way open or all the way closed B. normally open C. throttled depending on load D. controlled by suction pressure1482Which of the following may cause that excessively warm water leaves the condenser in a

289、 refrigeration plant?1483 too little cooling water; t much cooling water;too warm cooling water. 1482。冷凝器中冷却水太少或温度太高，会引起冷凝器出口水温过高。 A. only B. any of , and C. either or D. either or 1479 B 1480 C 1481 C 1482 C1483 If a refrigeration compressor is running continuously without lowering temperature as n

290、ormal in the refrigerator, the trouble may be _ 制冷压缩机持续运转但不降温，可能原因是制冷剂缺乏。 A. excessive condenser cooling water B. warm food in the refrigerator C. a shortage of refrigerant D. a shortage of compressor oil1484 The color of the flame on a halide torch without any refrigerant present is _ 1484对于卤素灯，无制冷

291、剂时火焰呈蓝色。 A. blue B. green C. orange D. purple1485 The compressor suction line conveys the refrigerant vapor from _ 1485压缩机吸人管路把制冷剂蒸汽从蒸发器输送到压缩机。A. condenser to evaporator B. evaporator to compressor C. compressor to condenser D. None of the above.1486 If an anchor windlass has been idle for some time

292、, you should _ 1486如果锚机有一段时间不用了，使用前应润滑 A. repack all valve stems B. lubricate it prior to use C. replace the foundation bolts D. balance the warping heads 1483 C 1484 A 1485 B 1486 B 1487 Water allowed to accumulate in the hydraulic system oil will cause an oxidation process producing by- products w

293、hich are normally _ 液压油含有的水分会引起氧化，产生胶质、酸性物质和残碳等。A. gums, acids, and varnishes B. removed by cellulose type filters C. neutralized by oil additives D. not removed by absorbent filters1488 It is possible to mount a double suction centrifugal pump impeller with the vanes facing in the wrong direction.

294、This would cause the pump _ 1488对于双叶轮的离心泵，如果叶片方向安装错误，将使泵效率下降。A. head capacity to improve B. discharge to be reversed C. efficiency to decrease D. slippage to decrease1489 A thermostatic expansion valve is properly controlling evaporator superheat. Adjusting this valve to lower the superheat will res

295、ult in a/an _ 1489热力膨胀阀用于控制蒸发器的过热度，当调节膨胀阀以减少过热度时，将使蒸发盘管流量过大 A. evaporator pressure decrease B. evaporator coil over-feed C. evaporator capacity increase D. expansion valve diaphragm rupture 1487 A 1488 C 1489 B1490 Air compressor receivers should be blown down at least _ 空气瓶每天应放残。 1491 Hydraulic mac

296、hinery failures are commonly caused by misalignment of the system components and by _ 1491液压机械的故障通常有系统部件失中和润滑油污染。 A. hydraulic fluid contamination B. excessive fluid friction C. turbulent fluid flow D. fluid pressure surges1492 A double suction centrifugal pump impeller has been installed in the rev

297、erse direction, and will _ 1492对于双叶轮的离心泵，如果反向安装，将需要更多功率来驱动离心泵轴，使泵效率下降。A. have a greater head capacity B. operate with increased impeller efficiency C. discharge through the suction side of the pump casing D. require more power to turn the shaft1493 If a centrifugal pump were continually operated wit

298、h the discharge valve closed , the _ 1493如果离心泵在排出阀关闭的情况下持续运转，将不可防止产生过热 A. motor controller overload would open B. pump would eventually overheat C. relief valve would continuously cycle open D. motor would overheat 1490 D 1491 A 1492 D 1493 B 1494 When you adjust a thermostatic expansion valve, _ 当调

299、节热力膨胀阀时，在作进一步调节前，应有足够时间让蒸发器工况稳定。 A. refrigerant must be bled off the sensing line before adjustments are made B. all refrigerant must be pumped into the receiver before adjustments are made C. time must be allowed for conditions to stabilize in the evaporator before further adjustments are made D. a

300、ll refrigerant must be muted through the dehydrator while changing the superheat setting1495 Hydraulic machinery failures are commonly caused by contamination of the hydraulic fluid and _ 1495液压机械的故障通常有系统部件失中和润滑油污染。A. fluid friction B. fluid turbulence C. component misalignment D. pressure surges149

301、6 The refrigeration system low pressure cutout switch is actuated by _ 1496制冷系统的低压控制器是由吸人管路的压力变化来产生动作的 A. an electric system manager B. a sensing bulb at the tail coil of the evaporator C. pressure changes in the suction line D. failure of the king solenoid valve 1494 C 1495 C 1496 C1497 A knocking

302、sound emitted from an unloaded air compressor is probably caused by _ 1497卸载后的空气压缩机发生敲缸，通常是由于活塞松动引起的 A. damaged intake valves B. excessively tight mounting bolts C. insufficient cylinder lubrication D. a loose piston1498 Which of the following statements is tree concerning any evaporator.?对于造水机来说，如果

303、凝水导电性好，说明凝水盐度过高。 A. High conductivity of the distillate indicates distillate salinity is excessive. B. Increasing the absolute pressure of the shell will increase the distillers capacity. C. Mesh separators are used in evaporators to filter the distillate. D. Reducing the brine density will reduce t

304、he heat lost overboard.1499 The sensing line for the low pressure cutout switch to a refrigeration system is located _ 1499制冷系统低压控制器的输入管路位于压缩机的吸入侧。 A. in 4he chill box B. before the receiver C. on the suction side of the compressor D. on the discharge side of the compressor 1497 D 1498 A 1499 C 1500

305、 In the production of freshwater from seawater through a process of heating and cooling, the cooling phase of production is usually called _ 通过加热和冷却的方法由海水中制造淡水，冷却过程称为“冷凝。A. evaporation B. distillation C. dehydration D. condensation1501 The process of boiling seawater in order to separate it into fre

306、shwater vapor and brine is usually defined as _ 1501使海水沸腾使之变成淡水蒸汽和盐水的过程，称为“蒸发。A. dehydration B. condensation C. evaporation D. dissolution1502 The purpose of the low pressure cut-out switch is to _ 1502制冷系统低压控制器的作用是在预先没定的压力下启、停压缩饥。A. maintain liquid refrigerant at the suction of the compressor B. ma

307、intain a preset suction pressure to the compressor C. start and stop the compressor at preset operating pressures D. operate at minimum efficiency 1503 Overheating of a hydraulic system may be a result of _ 1503液压油粘度不宜会引起液压系统过热。 A. changing pump discharge pressure in response to normal load variatio

308、ns B. a high oil level C. incorrect fluid viscosity D. continued slow re-circulation of the oil 1500 D 1501 C 1502 C 1503 C 1504 Condensate must be drained periodically from the air compressor receivers to prevent _ 空气瓶应定期放残，以防气动阀件误动作。 A. second stage cylinder lockup B. oil sump contamination C. fau

309、lty operation of pneumatic valves D. corrosion of air receiver baffles 1505 When a flash-type evaporator is to be secured for an extended period of time, the entire unit should be drained, cleaned, and _ 1505、如果闪发式造水机要停机一段时间，应放残、清洁并通大气。 A. completely filled with saltwater B. filled with de-scaling c

310、ompound C. tightly closed to exclude air D. vented to the atmosphere1506 Short cycling of a refrigeration compressor refers to _ 1506制冷压缩机“短循环，指的是压缩机启、停频繁。 A. frequently grounding out B. frequently starting and stopping C. running too fast D. running too slow 1504 C 1505 D 1506 B1507 The emergency b

311、ilge suction valve is typically used _ 当舱底进水，而且不能用其他方法排干时，使用应急舱底水吸口排水。 A. to inject cleaning additives when the bilges are extremely dirty B. when the main condenser becomes fouled, in order to provide additional cooling water circulation C. to connect the rose box to the independent bilge suction D

312、. if the bilges become flooded and they can not be emptied by any other1508 On all vessels equipped with refrigeration units of over 20 cubic foot capacity, _ 1508具有容积在20ft3以上制冷系统的船舶，必须有适宜的气体面罩(能防止所使用的制冷剂J产生的危害)或呼吸面具。A. a gas mask suitable for protection against each refrigerant used, or a self cont

313、ained breathing apparatus must be provided B. it is the sole responsibility of the chief engineer to ascertain that all members of the engineering department are familiar with the use of gas masks or breathing apparatus C. spare charges shall be carried for at least 50% of each size and variety of g

314、as masks and/or self contained breathing apparatus D. all of the above1509 Which of the listed types steam traps operates on the principle that hot water flashes to steam when its vapor pressure is rapidly reduced? 1509脉冲式阻汽器是基于“压力迅速下降，高温的水闪发成蒸汽原理工作的 A. Ball float B. Thermostatic C. Bimetallic D. Im

315、pulse 1507 D 1508 A 1509 D 1510 The heat gained per pound of refrigerant in the evaporator is known as the _ 蒸发器中，每磅制冷剂获得的热量，称为“单位制冷量。A. latent heat of vaporization B. sensible heat C. refrigerating effect D. specific heat of vaporization1511 The process of removing moisture from air is known as _ 1

316、511从空气中去除水蒸汽的过程称为“除湿。A. humidification B. dehumidification C. vaporization D. evaporation1512 A centrifugal bilge pump requires priming _ 1512离心式舱底水泵需要灌水，因为这种泵无干吸能力 A. primarily to lubricate the shaft seals B. due to the inability of this type of pump to lift water to cover the suction (eye) of the

317、impeller C. to initially unload the pump by having its head pressure equal to discharge pressure D. in order to overcome the potential energy of water in the discharge line 1510 C 1510C 1511 B 1512 B1513Which of the listed conditions can lead to cavitation in a 1514 centrifugal pump?1515离心泵吸入口有气泡，会引

318、起泵产生“气蚀现象。1516A. Vapor pockets formed in the suction flow stream1517 B. Rough casing volute surfaces C. Worn wearing rings1518 D. Heavy fluid in the flow stream15191514 Which of the following descriptions best identifies the operating principal of a flash-type evaporator715201514在闪发式造水机中，加过热的海永被喷射到真

319、空室(闪发室)。1521A. Sea water is heated to boiling temperature while under a vacuum.1522 B. Sea water is passed over heated plates in a thin film.1523 C. Heated sea water is injected into a vacuum chamber.1524 D. Sea water is forced through a heated eductor.15251515 If air at 95 C dry bulb temperature an

320、d 50% relative humidity is conditioned to 75 C dry bulb temperature and 50% relative humidity, it is an example of _ 15261515干球温度从95下降到75，相对湿度保持在50，这是一个制冷和除湿的过程1527 A. cooling only B. cooling and humidifying1528 C. cooling and dehumidifying D. adiabatic cooling15291513 A 1514 C 1515 C1516 What is a

321、function of the wearing rings used in most centrifugal pumps?绝大多数离心泵中使用的耐磨环，其中一个作用是将排出侧与吸入侧隔离。 A. Absorb erosion of high velocity discharge stream. B. Seal pump shaft against entry of air. C. Isolate the discharge side from the suction side. D. Dampen the turbulent discharge flow.1517 When liquid re

322、aches the compressor of a refrigeration system through the suction line, the condition is called _ 1517当液态制冷剂通过压缩机吸入管到达制冷系统的压缩机时，会产生“液击现象。A. flooding back B. superheating C. overflowing D. recycling1518 The term pour point is defined as the lowest temperature at which lubricating oils will flow _ 15

323、18滑油依靠重力能流动时的最低温度，称为“倾点。 A. rapidly B. by gravity C. through a standard orifice at a specified temperature D. at a rate of 60cc per second1519 A reciprocating air compressor is nmning roughly and vibrating excessively, indicating that the _ 1519往复式空气压缯机运转不平稳、振动严重，通常是由于机座螺栓松动引起的 A. compressor is over

324、loaded B. motor is overloaded C. foundation bolts are loose D. belts are too tight 1516 C 1517 A 1518 B 1519 C1520 Increasing the moisture content of conditioned air is known as _ 增加空气水蒸汽含量的过程，称为“加湿。 A. moisturizing B. dehumidification C. dampening D. humidification1521 In a radial piston pump, reve

325、rsal and control of fluid flow are accomplished by moving the _ 1521对于径向柱塞泵，通过浮环来实现流体方向和流量控制。 A. central valve B. radial plunger C. floating ring D. cylinder body1522 To maintain design discharge pressure from a centrifugal pump, the design clearance must be maintained between the _ 1522为了保持离心泵设计的排出

326、压力，在泵壳体和叶轮承磨环之间应保持设计间隙。 A. shaft and impeller B. motor and pump shaft C. casing and impeller wearing rings D. lantern ring and impeller1523 If a radial piston hydraulic pump fails to deliver rated fluid volume, the cause can be _ 1523如果径向柱塞式液压泵不能排出额定的流量，原因可能是吸人通道堵塞， A. contaminated fluid B. pitted t

327、hrust rings C. worn pintle bearings D. obstructed suctions passage1524 With respect to centrifugal pump impellers, which of the following descriptions represents the correct centrifugal pump classification?1524按照离心泵叶轮数量来分类，可分为单级和多级 A. Single stage or multistage. B. High pressure or low pressure. C.

328、Open or close coupled. D. Horizontal or vertical. 1520 D 1521 C 1522 C 1523 D 1524 A1525 The sum of the sensible heat and the latent heat of any substance is known as _ 任何物质的显热和潜热之和，称为“总热量。 A. total heat B. residual heat C. specific heat D. superheat1526 The static suction lift of a pump is the diff

329、erence in elevation between the _ 1526泵的静吸人压头是指当液体位于泵下面时泵的中心线与吸入侧液位之间的差。 A. centerline of the pump and the level of the liquid in the suction well when the source of liquid is below the pump B. centerline of the pump and the suction liquid level when the source of liquid is above the pump C. centerl

330、ine of the pump and the level of the discharge liquid D. liquid levels of the suction and discharge1527 The heat identified by only a change in temperature is known as _ 1527仅以温度改变表现出来的热量，称为“显热。 A. sensible heat B. latent heat C. total heat D. residual heat1528 The usual number of single-acting pist

331、ons used in a variable stroke axial-piston pump is_ 1528变甩轴向柱塞式泵使用的单作用式柱塞的数目一般是7个或9个(奇数个)。 A. 3 or 5 B. 5 or 7 C. 7 or 9 D. 9 or 11 1525 A 1526 A 1527 A 1528 C 1529An axial piston pump differs from a radial piston pump as the pistons of an axial piston pump are positioned _ 1530轴向柱塞式泵与径向柱塞泵不同之处在于，轴向

332、柱塞式泵的注塞相互平行并轴线平行。1531A. radially from the shaft B. parallel to each other and to the shaf1532 C. parallel to each other but at a right angle to the shaf1533 D. at an angle to each other and to the shaft15341530 In reference to air conditioning, when air attains the maximum mount of moisture it can h

333、old at a specific temperature, it is said to be _ 15351530在空调中，当空气获得在其特定温度下能含有的最多水蒸汽时，我们说空气处于饱和状态。1536A. superheated B. saturated C. condensed D. convected1537Why are removable sleeves installed on centrifugal pmnp shafts15381531离心泵泵轴上安装可拆卸式轴套，以便磨损后能经济地更换。1539 A. They make it easier to replace the p

334、ump shaft packing.1540 B. They can be economically replaced as they wear out.1541 C. They can be removed when it is necessary to lighten the weight of the pump1542 D. They increase the strength of the shaft.1543 1529 B 1530 B 1531 B1532 If a reciprocating air compressor has a knock occurring in freq

335、uency with its operating RPM, the cause is probably _ 如果往复式空气压缩机运转时经常发生敲击声，可能原因是轴系失中或主轴损。A. misalignment or worn main bearings B. insufficient cylinder lubrication C. defective or poorly fitted valves D. All of the above1533 Which of the following statements represents the advantage of rotary pumps

336、as 旋涡式泵与往复式泵相比的一个优点是它的排量大。 compared to reciprocating pumps? A. The high discharge pressure of the rotary pumps permits a larger volume of fluid per unit time than the reciprocating pump. B. Rotary pumps are capable of pumping more fluid than reciprocating pumps of the same weight. C. Rotary pumps oc

337、cupy only one-half the space of reciprocating pumps. D. Rotary pumps eliminate discharge slippage of the pumped liquid, while this does not hold tree for a reciprocating pump.1534 Which of the following factors will have the greatest effect on the heating load within a conditioned space? 渗热和通风对空调处所的

338、热负荷影响最大。 A. Solar gain. B. Infiltration and ventilation air. C. Occupants inside the space. D. Entertainment equipment within the space. 1532 A 1533 B 1534 B1535 Which of the following terms represents the form of heat removed from the refrigerant in the condenser of a refrigeration system?1535制冷系统冷

339、凝器中，制冷剂释放的热量包括：蒸发潜热、压缩热和过热。 A. Latent heat of vaporization. B. Heat of compression. C. Superheat. D. All of the above.1536 Which of the listed problems could produce a high lute pressure within a flash type evaporator?1536对于闪发式造水机，如果淡水泵透气管(至淡水泵吸入口的“平衡管)泄漏，将破坏真空，使绝对压力升高。 A. Production of high salinit

340、y distillate. B. Seawater feed temperature below 165C. C. A leak in the first stage demister. D. A cracked distillate pump vent line.1537 The dew point of air is reached when the wet bulb temperature is _ 1537当空气的湿球温度与干球温度相等时，该点称为空气的“露点。 A. twice the dry bulb temperature B. 102 above the dry bulb te

341、mperature C. 5C above the dry bulb temperature D. equal to the dry bulb temperature 1535 D 1536 D 1537 D1538 Increasing the speed of a rotary pump above its rated speed will result in which of the following conditions to occur?旋涡式泵超速运转，将使间隙增大。 A. Loss of suction B. Increased clearances C. Decreased

342、clearances D. Decreased slippage1539 The tendency for lubricating oil to thin out at high temperatures and thicken at low temperatures will be characterized by a _ 1539如果滑油在高温时变得稀薄，而在低温时变成浓厚，那么滑油的粘度指数低。A. low viscosity index B. high viscosity index C. high neutralization number D. low demulsibility

343、quality1540 The temperature at which water vapor in the atmosphere begins to condense is called the _ 1540大气环境下水蒸汽开始冷凝的温度，称为“露点温度 A. dew point temperature B. condensation temperature C. psychometric temperature D. absolute humidity temperature 1538 B 1539 A 1540 A1541One of the main differences betw

344、een the various types of screw pumps is in the _ 1542各种类型的螺杆泵主要区别之一螺杆的螺距不同。1543A. stuffing box diameter B. direction of rotation of the screws C. pitch of the screws D. type of driving gears1542 The FIRST thing to do to ensure that a refrigeration unit will not start while undergoing repairs, is to

345、_ 在进行维修工作时，为确保制冷装置不启动，应首先切断电路。A. secure and tag the electrical circuit B. place a crow bar in the flywheel of the unit C. inform all persons in the area not to start the unit D. make a log book entry1543 In a refrigeration system, the refrigerant rbs the latent heat of vaporization in the _ 在制冷系统中，制

346、冷剂在蒸发器中吸收蒸发潜热。 A. compressor B. condenser C. receiver D. evaporator 1541 C 1542 A 1543 D1544The only means of removing the latent heat of condensation from a 1545 refrigerant in the normal refrigeration cycle is by _ 1546在制冷系统中，去除制冷剂冷凝潜热的设备是冷凝器。1547 A. passing it through the expansion valve1548 B. c

347、ondensing refrigerant in the system condenser1549 C. passing the gaseous refrigerant through the heat1550 interchanger on the suction side of the compressor1551 D. maintaining a high pressure on the systems receiver15521545 With reference to a vessels structural integrity, the most significant chara

348、cteristic of a cryogenic liquid is its _ 15531545低温液体对船舶结构产生的最大危害是发生“冷脆。1554 A. capability of causing brittle fractures1555 B. highly corrosive action on mild steel1556 C. vapor cloud which reacts violently with saltwater1557 D. toxicity at atmospheric pressure1558The heat required to change a subst

349、ance from a solid to a liquid while at its freezing temperature, is known as the latent heat of _ 15591546在冰点温度下将物质从固态转变为液态所需的热量，称为熔化潜热o1560 A. fusion B. vaporization C. condensation D. sublimation1561 1544 B 1545 A 1546 A 1547 The degree to which the viscosity of an oil will change with a change in

350、 temperature is indicated by the _ 油的粘度随温度变化的程度，可用粘度指数来表示。 A. weight designation B. viscosity index C. pour point D. thermal change value1548 Which of the processes listed consumes the greatest amount of power while producing the greatest amount of heat?克服滑动摩擦需要消耗最大的功，同时产生最多的热量。A. Overcoming sliding

351、 friction. B. Overcoming rolling friction. C. Overcoming fluid friction. D. Overcoming oil wedge friction.1549 The heat required to change a substance from a liquid to a gas without experiencing a temperature change, is defined as the latent heat of _ 在温度保持不变的情况下，将物质从液态转变为气态所需要的热量，称为蒸发潜热。A. fusion B

352、. vaporization C. sublimation D. condensation1550 A distinguishing feature of an eductor, when compared to other pumps, is the _ 1550，喷射泵与其他形式的泵相比，最显著特点是无运动部件。 A. discharge end being smaller than the suction end B. small size of impeller C. lack of moving parts D. ease at which the wearing rings may

353、 be changed 1547 B 1548 A 1549 B 1550 C1551 When securing a flash - type evaporator for an extended period of time , you should _ 如果闪发式造水机要停机一段时间，应放残、清洁并通大气。A. fill the unit with saltwater B. fill the unit with de-scaling compound C. completely drain the unit D. tightly seal the unit to exclude air1

354、552 Which features of a centrifugal pump reduce the need for renewing worn impellers and pump casings?1552对于离心式泵来说，由于使用了可更换式耐磨环，减少了更换叶轮和泵壳的可能性。A. Close radial clearance between impeller hub and casing. B. Low rotational speed of impeller. C. Removable end plate. D. Replaceable impeller and casing we

355、aring rings.1553 A centrifugal pump may fail to deliver water when first started if the _ 1553离心式泵启动时如果不进行灌水，将不能正常泵水。 A. water seal pipe is plugged B. pump is not primed C. seal ring is improperly located D. impeller is flooded 1551 C 1552 D 1553 B 1554 Which of the devices listed is common to all t

356、ypes of pumps? 所有形式的泵，都具有功率端和流体端。 A. A power end and fluid end. B. A propeller and educator. C. A volute and impeller. D. A turbine and piston.1555 If a centrifugal pump vibrates and is noisy when operating, the cause could be _ 如果离心式泵运转时振动严重、噪声大，原因可能是泵轴弯曲。 A. worn gland sealing shaft B. worn wearin

357、g rings C. a bent shaft D. reversed pump coupling1556 Distilled water from an evaporator may be discharged into a potable water tank _ 造水机产生的淡水，通过三通式电磁阀的控制，排到日用水柜。 A. through a detachable hose connection B. after passing through an activated charcoal filter C. after chemical analysis shows it is fit

358、 for consumption D. through a solenoid operated three-way valve1557 If the capacity of a centrifugal pump decreases gradually over a long period of time, you should replace the _ 如果离心泵的排量在很长一段时间内逐渐下降，应更换承磨环。 A. packing gland B. mechanical seals C. lantern rings D. wearing rings 1554 A 1555 C 1556 D

359、1557 D1558 To absorb the wear resulting from impeller rotation and abrasives in the liquid, a centrifugal pump is usually fitted with _ 为了承受由于叶轮旋转和流体中磨粒而产生的磨损，离心泵通常需要装设承磨环。A. lantern tings B. bearings C. casing volutes D. wearing rings1559 Personnel working with refrigeration systems, and subject to

360、 the exposure of refrigerants should wear _ 如果对制冷系统进行维修工作，可能会接触制冷剂，人员应戴适宜的面罩。A. face shield B. a respirator C. rubber gloves D. an all purpose gas mask1560 The purpose of an air compressor unloading device is to _ 空气压缩机卸载设备的主要目的是推迟压缩过程，直到马达到达一定的转速。A. drain water from the air receiver B. drain water

361、from the cylinders C. delay the compression process until the motor is up to speed D. check pump alignment1561 The amount of moisture in a given sample of air, when compared with the amount of moisture the air could hold if totally saturated at the existing temperature of the sample, is called _ 空气含

362、有的水蒸汽量与其温度下处在全饱和状态时能携带的水蒸汽量相比，称为相对湿度。 A. absolute humidity B. specific humidity C. effective humidity D. relative humidity 1558 D 1559 A 1560 C 1561 D 1562Which of the following statements is correct relative to distillation 1563 plant operation.?蒸馏是这样一种过程：将海水蒸发，产生蒸汽，然后冷凝成淡水。A. Distillation is the p

363、rocess of boiling seawater to produce vapor which is condensed into fresh water. B. Evaporation is the second part of the distillation process where brine is removed. C. Brine is the result of condensed sea water vapor. D. Distillate is the product resulting from the evaporation of fresh water vapor

364、.1563If a centrifugal pump is driven by a constant speed electric motor and produces a discharge pressure less than designed, the cause is probably _ 如果由定速电动机驱动的离心泵，排量小于设计值，原因可能是承磨环磨损。 A. excessive pump speed B. excessive suction head C. worn wearing rings D. gross pump misalignment1564 The ratio of

365、 the weight of moisture contained in a given volume of air, to the weight of moisture that the same sample would hold if saturated, is called the _ 空气含有的水蒸汽量与其温度下处在全饱和状态时能携带的水蒸汽量相比，称为相对湿度 A. absolute humidity B. relative humidity C. specific humidity D. total humidity 1562 A 1563 C 1564 B1565 Which

366、of the listed chemicals can be routinely used to maintain tile hygienic quality of potable water?化学剂氯可用来保持饮用水的卫生质量。A. Hydrochloric acid B. Chlorine C. Sulfuric acid D. Zinc chromate1566 The steam coils in a high pressure evaporator used for saltwater service should be de-scaled with _ 1566高压蒸发器的蒸汽加热

367、盘管，应用钢丝刷去除水垢。A. a needle gun B. soap and water C. a wire brash D. a chipping hammer1567 The packing installed in the pump stutfing box is lubricated by _ 安装在泵填料箱的盘根由通过填料箱的泄漏液来润滑的。A. gravity and feed oil cups B. grease cups C. hand during installation D. leakage through the stuffing box1568 If you we

368、re operating a centrifugal water service pump with worn wearing rings , the _ 如果离心泵的承磨环磨损，排量将小于设计值。 A. pump would be very noisy B. pump would vibrate excessively C. pump would develop insufficient flow D. stuffing box would leak excessively 1565 B 1566 C 1567 D 1568 C1569 Which of the following stat

369、ements is correct regarding an oil with a high viscosity index?粘度指数大的油，温度发生明显变化，其粘度变化很小。A. A large change of viscosity occurs with a minor change in temperature. B. No change in viscosity occurs with any change in temperature. C. Very little change in viscosity occurs with a significant change in te

370、mperature. D. The viscosity of the oil increases with an increase in temperature.1570 Brine density in a distilling plant is measured with a/an_ 蒸馏装置中盐度是由盐度计来测量的。 A. psychrometer B. salinometer C. anemometer D. sphygmomanometer1571 One of the main functions of wearing rings, as used in a centrifugal

371、 pumps, is to_ 离心泵使用承磨环；其中一个主要作用是防止泵壳和或叶轮磨损 A. maintain radial alignment between the pump impeller and casing B. absorb all impeller shaft end thrust C. prevent water leakage to the atmosphere D. prevent wear of the pump casing and/or impeller 1569 C 1570 B 1571 D1572For safe storage, the maximum al

372、lowable temperature to which refrigerant bottles should be exposed is _ 1573为了平安起见，制冷剂瓶接触的温度不得高于125 1574A. 100C B. 125 C C. 150 C D. 175 C 15751573 After installing a new hydraulic pump in a system, what special attention should be given to the hydraulic system? 15761573在液压系统中安装一台新的液压泵后，应经常检查粗、细滤器。1

373、577A. The relief valves in the system should be readjusted.1578 B. The filters and strainers should be checked frequently.1579 C. All system pressure should be readjusted.1580 D. The system should be drained and renewed with a fluid of different operating characteristics.15811574 An un-loader is ins

374、talled on an air compressor to _ 1582空气压缩机的卸载设备能卸走启动时除了摩擦负荷外的所有负载1583 A. bypass the high pressure stage to the low pressure stage on 100% of the air compressors in service1584 B. prevent excessive inter-stage pressure buildup1585 C. control compressor discharge pressure1586 D. remove all but the fri

375、ctional load during starting1587 1572 B 1573 B 1574 D1575 Which of the following is operated from the main engine room console on an automated vessel? 在自动化船舶上，消防泵和滑油泵是由机舱集控室来操作的。A. Fire pump and lube oil pump B. Lube oil pump and distilling plant C. Distilling plant and shaft alley door D. Shaft all

376、ey door and fixed C02 release1576 Ammonia when used as a refrigerant is valuable because of its high efficiency, it is however_ 氨用作制冷剂，效率高，但是它有毒、易燃、易爆。A. toxic B. flammable C. explosive D. all of the above1577 Which of the following terms is used to identify the pressure of the liquid entering a pum

377、p?通常用“吸人压头来表示进入泵流体的压力。 A. Suction head B. Pump head C. Discharge head D. Total head1578 When subjected to high heat from a open flame, or an electric heating element, which of the listed refrigerants will break down and produce phosgene gas?制冷剂与高温接触后，会分裂并产生光气。 A. CO2 B. Methyl chloride C. R- 22 D. S

378、ulphur dioxide 1576 D 1577 A 1578 C 1579 Demulsibility of a lube oil is defined as _ 滑油的抗乳化性能是指油能从水中别离的能力。 A. the abili of oil to separate from water B. the temperature at which oil flows rapidly C. a measure of the water in a lube oil system D. an emulsion of different grades of oil1580 The clearan

379、ce volume for a single stage compressor is defined as the space created between the _ 单级压缩机的余隙容积是指当活塞处于上止点时，活塞与气缸盖之间的容积，包括到顶部第一道活塞环沿活塞周围的容积以及气阀下的容积 A. top of the piston and bottom side of head, with the piston at BDC B. piston and head, including the space around the piston to the top of the upper r

380、ing and under the valves, with the piston at TDC C. bottom of the piston and bottom side of the head at TDC, regardless of upper ring location and valve placement D. top of the piston and bottom side of the head at TDC as compared to that which exists between the top of the piston and bottom side of

381、 head at BDC 1579 A 1580 B1581 If the discharge valve is closed before the drive motor is stopped, which of the following types of pumps will most likely be damaged?如果电动机停车前，齿轮泵的排出阀关闭，泵将损坏。 A. Centrifugal B. Gear C. Propeller D. Turbine1582 When the relief valve opens it discharges high pressure ref

382、rigerant vapor to the _ 当制冷压缩机的释放阀翻开时，将高压的制冷剂气体排到压缩机的吸入侧。A. liquid strainer B. refrigerant inlet of the condenser C. inlet side of the evaporator D. suction side of the compressorThe ability of an oil to separate cleanly from an oil and water mixture is referred to as its _ 油的抗乳化性能是指油能从油水混合物中别离的能力 A

383、. precipitation number B. neutralization number C. pour point D. demulsibility 1581 B 1582 D 1583 D 1584 Which of the following statements is true concerning the over all efficiency of air compressors?从效率角度看，双级空气压缩机的效率高于单级压缩机。 A. High pressure compressors are more efficient than low pressure compres

384、sors. B. Mechanical efficiency divided by compressor efficiency will equal the overall efficiency of the compressor unit. C. Two stage compressors are generally more efficient than single stage compressors. D. The volumetric efficiency is decreased in multistage compressors.1585To obtain maximum eff

385、iciency, two stage air compressors are usually_ 1586为了提高效率，双级空气压缩机装有中冷器。 A. horizontally mounted B. never fitted with intake filters C. fitted with intercoolers D. operated in an unloaded condition at all times 1584 C 1585 C1586The function of the hydraulic telemotor transmitter used in an electro-h

386、ydraulic1587 steering gear system is to _ 电动液压舵机系统中的遥控液压发送器的功能是将液压信号发送到接收装置。A. transmit the rudder angle to the bridge indicator B. prevent the control linkage from striking the stops when hard over C. automatically purge all entrained air from the system D. send hydraulic signals to the receiving u

387、nit1587 Which of the following statements is/are true regarding hydraulic pumps in general?对于齿轮泵，排量的改变只能通过改变泵的转速来实现。A. Variable volumes can be obtained with gear pumps only by variation of the pump drive speed. B. A radial piston pump houses sliding pistons in a stationary cylinder block through whi

388、ch passes a rotating pintle or ported shaft. C. The amount of fluid displaced per revolution of an axial piston rotary pump is dependent on the angle formed between the cylinder block and valve plate. D. All of the above.1588 R- 12 is generally considered to be a safe, nontoxic, nonflammable, and no

389、n-explosive refrigerant. It can, however, become highly toxic whenR12制冷剂无毒、不易燃、不易爆。但与明火接触时，会有很高的毒性 A. superheated outside the system B. in contact with an open flame C. heated to the boiling point D. All of the above. 1586 D 1587 A 1588 Belectn)1589 A refrigeration system contaminated with moisture

390、can be affected by _ 制冷系统中存在水分，会形成酸性物质、沉淀，并在膨胀阀处结冰。A. acid formation B. sludge formation C. ice in the expansion valve D. All of the above1590Some chloronated flourocarbon refrigerants may decompose into a toxic irritating gas if it is _ 氟氯化饱和碳氢化合物的制冷剂与高温接触后，会分解出对人体有害的氟化氢、氯化氢及光气。A. stored at tempera

391、tures below 60 degrees Fahrenheit B. charged into a system having copper fitting C. allowed to mix with compressor oil D. exposed to an open flame or hot surface1591 Which of the following statements describes the relationship between viscosity and specific gravity?如果不明确或限制其他条件，粘度与密度没有直接关系。 A. Liqui

392、ds with different viscosities will always have the same specific gravity. B. Liquids with different viscosities will never have the same specific gravity. C. Viscosity and specific gravity are directly proportional. D. Viscosity and specific gravity are not related in that one does not define or lim

393、it the other. 1589 D 1590 D 1591 D1592 The delivery rate of a variable stroke axial piston hydraulic pump is controlled by varying the position of the _ 变量轴向柱塞式液压泵的输出速度是通过改变倾斜盘的位置来控制的。A. slide block B. tilting box C. pintle D. reaction ring1593 The pressure of a liquid leaving the pump can be referr

394、ed to as the _ 液体离开泵时的压力，称为排出压力。 A. total head B. discharge head C. net positive suction head D. suction head1594 Tube leaks in the distillate cooler of a two stage flash evaporator will result in _ 1594两级闪发式造水机，淡水冷却器管子泄漏将会造成淡水污染。 A. loss of second stage vacuum B. contamination of the distillate C.

395、lower feed inlet temperature D. contamination of the second stage condenser1595 Air leakage between the shaft and stuffing box packing in a centrifugal pump is 在离心泵中，泵轴和填料箱盘根之间的漏气是通过液封来防止的。A. a compressed packing gland B. lantern rings between the packing rings C. a liquid seal D. the stuffing box g

396、land1596 The suction- force principle of operation is a typical characteristic of _ 往复泵是基于“吸力原理来工作的。 ，A. centrifugal pumps B. jet pumps C. propeller pumps D. reciprocating pumps1597 Hydraulic pumps most commonly used in steering systems are of the _ 舵机系统中使用的液压泵通常是轴向柱塞泵。 prevented by _ A. lobe type B

397、. screw type C. axial piston type D. volute type 1592 B 1593 B 1594 B 1595 C 1596 D 1597 C 1598 An additive used to improve the ability of a lube oil to reduce friction is known as a/an _ 用来改善滑油减少摩擦能力的添加剂称为“极压剂。 A. suppressant additive B. dispersant additive C. extreme pressure additive D. viscosity

398、 improver additive1599 In an electro-hydraulic steering gear system, when will the variable displacement pump be placed on stroke?1599对于电动液压舵机系统，当舵角与舵轮位置不同时，变量泵才会产生吸排油的动作?A. When the helm is at any angle other than amidships. B. When the six-way valve is opened. C. When the ram relief valves hft. D.

399、 When the rudder angle is different from the position of the helm.1600 Which of the listed operations will cause an automatically controlled refrigeration compressor to restart?吸人压力升高会引起自动控制的制冷压缩机重新启动。 A. Closing of the solenoid valve B. Closing of the expansion valve C. An increase in the suction p

400、ressure D. Decreasing the suction pressure 1598 C 1599 D 1600 C1601 Saltwater is typically provided to a refrigeration system to _ 向制冷系统提供海水，是用来冷却制冷剂气体。A. cool the expansion valve B. prevent refrigerant superheating C. condense the refrigerant gas D. prevent motor overheating 1602 Under normal opera

401、ting conditions, the rudder is hydraulically locked unless _ 在正常工作状态下，舵是被液压锁紧的，除非控制系统发出舵角信号。 A. the manual trick wheel is engaged for steering B. the variable stroke pump is off stroke C. a redder order is given by the control system D. an electric power system failure occurs at the steering gear 16

402、03 Which of the following statements is correct concerning the viscosity of lubricating oil?滑油的粘度是表示滑油流动时的内阻力。A. Viscosity will increase as temperature increases. B. Viscosity is a measure ofa fluids internal resistance to flow. C. Viscosity will decrease as temperature decreases. D. Viscosity is no

403、t dependent on temperature. 1601 C 1602 C 1603 B1604 The pour point of lubricating oils is affected the most by which of the following?滑油的倾点受石蜡含量的影响最大 A. Extensive centrifuging. B. Wax content. C. Water content. D. Acid content.1605 The viscosity of an oil is a measure of its _ 油的粘度是表示油流动时的内阻力。A. we

404、ight B. internal friction C. demulsibility D .S.A.E. number1606 Although lube oils used in the main lubricating service systems should have a relatively high flash point to avoid ignition, they can create smoke and fire hazards when they _ 1606尽管润滑系统中的滑油具有相对较高的闪点以防着火，但是当它们与温度特别高的外表接触时仍会产生烟雾甚至火灾。A. a

405、re exposed to a vacuum B. come in contact with extremely hot surfaces C. are reduced in temperature to just above the pour point D. become extremely agitated or aerated1607 Hydraulic cranes must be properly warmned-up before being operated because _ 1607液压克令吊使用前应首先进行适当暖机，以确保液压油处在适宜的粘度 A. warm-up all

406、ows the hydraulic system to become charged with oil B. warm-up allows the relief valves to be properly tested C. hydraulic strainers operate only during the warm-up period D. hydraulic fluid must be at the proper viscosity 1604 B 1605 B 1606 B 1607 D1608 Which of the following statements describes t

407、he function of an air compressor intake filter?1608空气压缩机进气滤器的作用是防止空气中携带的固体颗粒产生损坏作用。A. Protects against suction valve float. B. Provides a positive pressure on the air inlet valves. C. Prevents lubricating oil contamination of the compressed air supply. D. Protects against the damaging effects of air

408、borne solid particles.1609 Which of the listed characteristics of lube oil are the most important to the engineer from an operational standpoint?1609从操作观点来看，滑油的粘度、酸值和抗乳化性能等指标最重要。A. Ash content, carbon residue, and gravity B. Viscosity, acidity, and demulsibility C. Pour point, flash point, and preci

409、pitation number D. Auto-ignition point, viscosity index, and film strength1610 A salinity indicating system functions on the basic principle of measuring the _ 1610盐度指示仪是通过测量水的导电性来测量盐度。 A. electrical inductance of water B. electrical conductivity of water C. specific gravity of water D. hydrogen ion

410、 concentration of water 1608 D 1609 B 1610 B1611 In a flash type evaporator, all saltwater headers are vented through individual vent cocks to the _ 1611在闪发式造水机中，所有的海水加热器通过各自的透气管通大气。A. saltwater heater shell B. second-stage condenser C. atmosphere D. second-stage flash chamber1612 An axial piston, v

411、ariable stroke pump is used in a vessels hydraulic steering gear. Under pressure, oil continually leaks out from between the valve plate/ cylinder barrel and will _ 1612船舶舵机系统中使用轴向变量柱塞泵。在压力下，液压油持续地从阀片和套筒之间 漏出，如果不连续地把泵壳中的油排掉，将会对油泵产生损坏。 A. cause loss of hydraulic oil from the system B. result in extre

412、me damage to the pump C. cause damage to the pump if not continually drained from the pump casing D. result in the system high side pressure to substantially drop off 1611 C 1612 C1613 A centrifugal pump vibrates excessively during operation. Upon disassembling the pump it is found that the impeller

413、 is out of balance. Without an available spare, you should _ 1613离心泵工作时，发现振动很大。拆卸泵时，发现叶轮不平衡。如果没有备用叶轮，可以通过机加工的方法去除较重一侧的金属。 A. drill holes through the heavy side of the impeller until it balances B. weld counterweights to the light side of the impeller C. remove metal from the heavy side by machining

414、in a lathe D. acid wash and scrape the heavy side until it balances1614 Moisture is removed from a refrigeration system by _ 1614。制冷系统中的水分通过除湿器来去除。 A. bleeding refrigerant from the condenser B. opening a drain petcock on the oil separator C. condensing the water in the heat exchanger D. using a dehy

415、drator cartridge 1613 C 1614 D1615 Why will a two stage flash type distilling plant tend to operate more efficiently when operating in cold seawater?1615当海水温度较低时，两级闪发式造水机的效率较高，因为闪发式的真空度提高了 A. The colder seawater passing through the condnser tube bundles of the various stages increases evaporator vac

416、uum. B. The amount of heated feed water discharged from the feed water heater after condenser is increased. C. Fewer non-condensable gases are created by the flow of colder seawater. D. More seawater is allowed to pass through the first stage overflow weir.1616 Moisture in the refrigerant may _ 1616

417、、制冷系统中的水分会在膨胀阀座结冰，并会减少制冷剂的流量。A. freeze on the expansion valve seat and reduce the flow of liquid refrigerant B. emulsify the oil in the condenser C. freeze in the king valve D. clog the oil trap1617 The tendency of a flammable liquid to vaporize is indicated by its _ 1617可燃液体的蒸发趋势可以用闪点来表示 A. ignitio

418、n temperature B. flash point C. flammable range D. convection index 1615 A 1616 A 1617 B1618 When the propeller blades are integral with the hub, the propeller is called a _ 1618当螺旋桨的桨口子与桨毂是整体式时，这种螺旋桨称为整体式螺旋桨。A. built up propeller B. solid propeller C. controllable pitch propeller D. suction back pr

419、opeller1619 Moisture in a refrigeration system can cause _ 1619制冷系统中的水分会造成膨胀阀结冰，系统管系腐蚀并使温度调节不正常。 A. freezing the expansion valve closed B. corrosion of system piping C. improper temperature regulation D. all of the above1620 Which of the problems listed could be indicated if a sight glass in the ref

420、rigerant liquid line is full of bubbles? 1620如果制冷剂液态管路中的示液镜充满气泡，可能说明制冷剂缺乏。 A. Proper refrigerant charge. B. Faulty expansion valve. C. Insufficient refrigerant. D. Solenoid valve stuck open.1621 Which of the following statements describes the functions of a reservoir used in a hydraulic system?1621液

421、压系统中使用贮油器，其作用有散发热量、去除外界杂质和别离空气等 A. Dissipate heat. B. Trap foreign matter. C. Separate air from the oil. D. All of the above. 1618 B 1619 D 1620 C 1621 D 1622 Compared to a constant pitch propeller, a controllable pitch propeller _ 1622与定距桨相比，调距桨更能有效地使用发动机的功率。意即不管船舶在任何工况下，调距桨均能给予主机发出全部功率的能力。A. more

422、efficiently uses available engine power B. operates at a lower efficiency at a fixed speed C. produces the same torque at lower engine power D. develops its rated power at a lower speed1623 A liquid indicator sight glass is useful in determining whether or not a refrigeration system is sufficiently

423、charged. It is generally located in the _ 1623，制冷系统示液镜位于高压液态管路。A. high pressure liquid line B. low pressure liquid line C. high pressure vapor line D. low pressure vapor line1624 One distinct advantage of flash type evaporators, as compared to most other evaporators, is that in a flash evaporator _

424、1624与普通造水机相比，闪发式造水机最明显的优点是结垢问题大为减轻。 A. high temperature distillate can be re- circulated to induce additional flashing B. scale formation is not a severe problem C. cold shocking is more effective in removing scale D. water purity is greatly increased at high capacity 1622 A 1623 A 1624 B1625 Dual e

425、lectro-hydraulic steering units usually operate _ 1625电动液压舵机工作时，有一台泵处于备用状态。A. with both pumps on line at the same time B. with one pump on standby C. with the follow-up gear disconnected D. only when the redder is moved amidships1626 If a liquid sight flow indicator in a refrigeration system shows g

426、as bubbles in motion passing inside of the glass, there is _ 1626如果制冷剂液态管路中的示液镜充满气泡，可能说明制冷剂缺乏。 A. too much refrigerant in the system B. oil entrained in the refrigerant C. less than a full charge of refrigerant in the system D. ice crystals forming in the refrigerant 1625 B 1626 C1627 The bilge syst

427、em has been performing well; however, the aft st engine room bilge- well suddenly fails to be pumped out. Which of the following should be done first to deter-mine the cause?16281627舱底水系统工作正常，但是右舷尾部污水井突然不能泵出。在查找原因前，首先应试图泵另一个污水井来判断是否整个系统受到影响。1629A. Open the bilge pump for inspection1630 B. Remove eac

428、h of the manifold valves.1631 C. Remove only the manifold valve to the affected bilge-well.1632 D. Attempt to pump out another bilge well to determine if the entire system is affected.16331628 If one hydraulic pump of an electro-hydraulic steering unit fails, the vessels steering can be initially an

429、d best maintained by using the _ 16341628电动液压舵机的一台液压泵发生故障，可以通过使用备用泵使舵机系统保持正常运转。1635A. trick wheel B. accumulator C. standby pump D. telemotor16361629 A sight glass is installed in the liquid line to indicate the condition of the refrigerant charge and may also indicate the _ 16371629制冷系统液态管路中的示液镜可用来

430、表示制冷剂的充注状况，也可用来显示系统中足否有水分。1638 A. condition of the expansion valve B. moisture in the system1639 C. condition of the compressor suction valves1640 D. condenser temperature1641 1627 D 1628 C 1629 B 1630 Which of the filter/strainer units listed permits you to clean the dement while leaving the system

431、 on the line?1630双联式滤器能在脱离管路情况下清洗滤器芯件。A. Simplex B. Duplex C. Canister D. Bypass1631 A liquid sight flow indicator in a refrigeration system is examined and gas bubbles are noted in motion with the fluid flow. This means _ 1631如果制冷剂液态管路中的示液镜充满气泡，可能说明制冷剂缺乏。A. the system is fully charged B. there is a

432、ir leaking in from the condenser C. ice crystals are forming in the refrigerant D. the system contains less than a full charge of refrigerant1632 Less scale formation occurs in a flash evaporator than in a submerged tube evaporator because _1632闪发式造水机最明显的优点是结垢问题入为减轻，因为在热交换面上没有发生沸腾现象。 A. the distilla

433、te produced has greater purity B. no boiling occurs on heat transfer surfaces C. evaporation occurs at a higher rate D. the incoming feed is at a higher temperature 1630 B 1631 D 1632 B1633 Vessel propellers are classified as being right hand or left hand. A right hand propeller turns clockwise when

434、 viewed from _ l633从船尾方向看，正转时顺时针旋转的螺旋桨，称为右旋桨。A. the bow B. the stern C. the port side D. the starboard side1634 The primary reason low pressure evaporators produce distillate more efficiently, and with less scale formation, than high pressure evaporators is _ 低压造水机与高压造水机相比，效率高而且水垢形成少。其主要原因是蒸发是在真空进行的

435、。 A. evaporation is accomplished in a vacuum B. due to the higher temperature of the incoming feed C. due to the latent heat of evaporation principle D. evaporation in a submerged medium produces more distillate 1633 B 1634 A1635 If the refrigeration compressor crankcase is sweating, the cause may b

436、e due to _ 1635如果制冷压缩机曲柄箱冒汗，原因可能是液态制冷剂返回到压缩机。A. a shortage of refrigerant B. the compressor running continuously C. liquid refrigerant returning to the compressor D. the compressor short cycling on the high pressure cutout1636 When normal operating pressure is applied to the hydraulic oil used in a

437、high-pressure system, the oil _ 1636当正常的工作压力作用于高压系统中的液压油时，油的体积将减少。A. viscosity will decrease B. volume will increase C. volume will decrease D. pour point will be reduced1637 Most solenoid valves are actuated by _ 1637绝大多数电磁阀是受电磁铁的作用来工作的。 A. a spring B. an electromagnet C. the force of gravity D. re

438、frigerant pressure 1635 C 1636 C 1637 B1638 Increased internal leakage, in addition to poor hydraulic system response, and inadequate lubrication, is the result of _ 1638液压系统反响慢、润滑不良，而且内部泄漏大，往往是由于液压油的粘度低引起。 A. pump bearings in poor condition B. excessively worn actuator-piston packing C. broken dire

439、ctional control valve centering springs D. low hydraulic oil viscosity1639 The structural members of the hull extending in a fore and aft direction are called _ 1639沿船舶首尾方向布置的结构件，称为纵梁。 A. frames B. joiners C. longitudinals D. knees1640 When there is no movement of the rams on an electro-hydraulic st

440、eering gear, the tilting box of the running pump is _ 1640当电动液压舵机的撞杆不运动时，油泵的倾斜盘处在中央位置。A. set for maximum torque B. on the purge and vent stroke C. in the neutral position D. rotating backwards1641 Which characteristic or condition will have the greatest effect on increasing a hydraulic oils viscosit

441、y? 1641压力将会引起液压油的粘度增大。 A. Pour point B. Cloud point C. Vacuum D. Pressure 1638 D 1639 C 1640 C 1641 D 1642 Rotation of the steering wheel on the navigation bridge initiates oil pressure being applied to the steering gear rams by _ 1642驾驶台舵轮转动，将改变倾斜盘的角度或浮环的偏心距，使得油压作用在舵机的撞杆上。A. regulating the oil flow

442、 with the six-way valve B. moving the automatic differential valve C. moving the receiving tele-motor which regulates the two-way valve D. varying the angle of a tilting box or eccentricity of a floating ringA knocking sound from one cylinder of an operating air compressor indicates_1643空气压缩机运转时，一个气

443、缸发生敲缸，原因是阀片松动。A. a defective or broken high pressure un-loader B. a loose valve plate C. excessive overload D. no compression1644 Sluggish response or action of the hydraulic actuators may be a result of _ 1644液压油粘度过高会引起系统反响迟钝。 A. insufficient load B. excessively high oil viscosity C. relief-valve p

444、ressure setting too high D. reservoir level being maintained two inches above normal 1642 D 1643 B 1644 B1645 A swing check valve is used in a pipeline to _ 1645管系中单向阀只允许流体以一个方向流动。 A. maintain a preset pressure on the line B. closely regulate the amount of flow C. relieve excessive pressure on the l

445、ine D. allow flow in one direction only1646 When the desired rudder angle is attained by a typical double ram electro- hydraulic steering gear, the _ 1646对于两撞杆的液压舵机，当到达所需要的舵角时，追随机构将使油泵不产生吸排作用，A. ram relief valves bypass oil to stop rudder movement B. six-way valve shifts to the neutral flow position

446、 C. steering pump electric motor is de- energized by the transfer switch D. follow-up gear takes the hydraulic pump off stroke1647 A refrigeration system compressor crankcase is sweating or unusually cold. This is an indication of _ 1647如果制冷压缩机曲柄箱冒汗，原因可能是液态制冷剂积聚在曲柄箱。 A. a shortage of refrigerant in

447、the system B. air in the system C. an accumulation of liquid refrigerant in the crankcase. D. a shortage of oil in the crankcase 1645 D 1646 D 1647 C1648 Operating a rotary pump at speeds in excess of design requirements could cause _ 1648旋涡泵超速运转，会引起剥蚀和过度磨损。 A. decreased clearances between rotating

448、parts B. decreased slippage to the suction side of the pump C. air binding in the discharge ports D. erosion and excessive wear1649 Refrigeration system compressor crankcase sweating is an indication of _ 1649。如果制冷压缩机曲柄箱冒汗，另一个原因可能是系统中循环的滑油过多。 A. insufficient lube oil circulating through the system B

449、. excessive circulation of lube oil through the system C. insufficient refrigerant in the system D. an overworked compressor1650 Which bearing will carry the load on two small points diametrically opposite to each other?1650对于球轴承，负荷是由直径方向相对的两点来承受。 A. Needle B. Tapered miler C. Roller D. Ball 1648 D

450、1649 B 1650 D1651 Sweating of the refrigeration system compressor crankcase is caused by _ 1651如果制冷压缩机曲柄箱冒汗，原因可能是过多的制冷剂返回到压缩机。A. too much superheat B. insufficient superheat C. suction pressure too low D. excessive refrigerant returning to the compressor1652 An increase in rotor clearances in a rota

451、ry pump will _ 1652旋涡泵转子间隙增大会引起泵排量减少。 A. increase discharge pressure B. decrease pump capacity C. decrease pump cavitation, D. decrease reaction ring clearance1653 The internal force of a material, which tends to resist deformation when subjected to external forces, is known as _ 1653物质承受外力时，能抵抗变形的内

452、力，称为“应力。A. stress B. strain C. shear strength D. ultimate tensile strength1654 In an electro-hydraulic steering system, redder movement is maintained in close synchronization with the steering wheel position by means of the _ 1654在电动液压舵机系统中，通过追随控制，舵的运动与舵轮位置构成闭环。 A. trick-wheel B. follow-up control C

453、. six-way valve D. Rapson slide 1651 D 1652 B 1653 A 1654 B 1655 Crankcase sweating in a refrigeration system is caused by _ 1655口果制冷压缩机曲柄箱冒汗，另一个原因可能是系统中循环的滑油过多。 A. a stuck solenoid valve B. a shortage of refrigerant C. too much oil in circulation D. too much superheat1656 If a refrigeration system

454、compressor crankcase is sweating, you should _ 1656n果制冷压缩机曲柄箱冒汗，应调节热力膨胀阀到正常位置，A. add refrigerant to the system B. adjust the thermal expansion valve to the proper setting C. adjust the float valve to the proper holding pressure D. open the hand expansion valve1657 A multistage centrifugal pump can b

455、e BEST described as having _ 1657多级离心泵是指两个或多个口卜轮封闭在一个泵壳内并安装在一根轴上。 A. two or more impellers housed together in one casing and mounted on a single shaft B. a single stepped impeller mounted in a progressively staged casing C. a large radial clearance between the impeller and casing to prevent overheat

456、ing due to friction D. an increase in the discharge velocity of the liquid with a corresponding decrease in pressure through the stages 1655 C 1656 B 1657 A 1658 Propeller pitch speed minus ship speed divided by the propeller pitch speed is termed _ 1658螺旋桨螺距的速度(船速)螺旋桨螺距的速度，即“滑失比。A. apparent slip B.

457、 true slip C. pitch D. propulsive efficiency1659 Which of the devices listed, when used on an electro-hydraulic steering gear, keeps the movement of the redder closely in step with the steering wheel?1659在电动液压舵机系统中，通过追随装置，舵的运动与舵轮位置保持同步。 A. The follow-up gear. B. The redder angle indicator. C. The sy

458、nchronous electric transmitter. D. A rudder angle limit switch.1660 The sensible heat of air is dependent upon the _ 1660空气的显热取决于干球温度。 A. dry bulb temperature B. wet bulb temperature C. saturation temperature D. water vapor superheat 1658 A 1659 A 1660 A1661 If an air compressor is used to supply co

459、mpressed air to outlets throughout the engine room and on deck of a vessel, the system is known as the _ 1661如果空气压缩机用来向机舱内和甲板上的有关接口提供压缩空气，该系统称为日用空气系统。 A. combustion control air system B. supply air system C. ships service air system D. low pressure deck air system1662 When it is necessary to open a

460、refrigeration system for repairs and the system will be open for more than a few minutes, the open ends of the system should be _ 1662如果要对制冷系统进行维修工作，系统需要翻开一段时间，系统的开口端应塞住。A. dehydrated B. purged C. plugged D. evacuated1663 If an air compressor is used to supply air primarily to the combustion control

461、 system and other pneumatic controllers, the entire system is known as the1663如果空气压缩机用来向燃烧控制系统和其他气动控制器提供压缩空气，该系统称为控制空气系统。 A. control air system B. forced draft air system C. supply air system D. ships service air system 1661 C 1662 C 1663 A1664 A cracked diaphragm in a thermostatic expansion valve w

462、ill cause the valve to1665 _1664热力膨胀阀膜片损坏将引起膨胀阀关闭。A. return to a neutral position B. flood the evaporator C. open D. close1665 In order to distribute the side pressures over a wide area of the cylinder walls and liners, which of the listed types of pistons are used in modem low pressure air compress

463、ors?1665现代低压式空气压缩帆通常采用筒状活塞，将侧向压力分布在较大的气缸壁和气缸套面积上。A. Differential B. Trunk C. Barrel D. Valve-in-head 1666 Which of the listed operating conditions would have the greatest effect on the volumetric efficiency of an operating reciprocating air compressor?1666对于运转中的往复式压缩机，头部垫片泄漏将对容积效率产生很大影响。 A. The dens

464、ity of the air entering the compressor. B. The temperature of the air entering the compressor C. The designed rotating speed of the compressor. D. A leaking head gasket. 1664 D 1665 B 1666 D1667Broken valve strips in an operating low pressure, air compressor will cause 1668 _1667空气压缩机阀片损坏将使排量下降。 A.

465、an immediate crankcase explosion B. oil contamination in the compressed air C. a decrease in compressor capacity D. no immediate loss of the compressed air capacity1668 Which of the problems listed represents the major difficulty encountered with thermal expansion valve operation?1668热力膨胀阀阀座和阀芯积聚水分或

466、杂质会对膨胀阀的工作造成影响。 A. Lube oil passing through the system. B. Moisture or foreign matter collecting at the valve seat and orifice. C. Variable spring tension caused by the changing temperature. D. Frost on the liquid line. 1667 C 1668 B1669A viscous film of oil collected between the valve face and seat

467、 of a low1670 pressure reciprocating air compressor will _1671 1669低压往复式空气压缩机，气阀面与阀座之间积聚油膜，将造成气阀开、关延迟。 A. prevent the valve from wire drawing B. retard the opening and closing of the valve C. have no effect on compressor operation D. provide quieter valve operation1670 If the pump for a hydraulic an

468、chor windlass is over heating, the cause may be _1670如果液压锚机的油泵过热，原因可能是油泵排出压力过高。 A. increased pump speed B. excessive pump discharge pressure C. too low of a tilting box angle D. low pump speed 1669 B 1670 B1671If a refrigeration compressor were short cycling on the low pressure 1672 cutout switch, t

469、he probable cause for this might be the _16731671膨胀阀滤器污垢，会引起低压控制器频繁动作，造成压缩机起、停频繁。1674A. system was overcharged with refrigerant1675 B. high pressure switch was improperly adjusted1676 C. expansion valve strainers were fouled1677 D. suction valves were leaking slightly16781672 The part of the anchor

470、windlass that engages the anchor chain for lifting is called the _16791672锚机装置中，锚链轮用来啮合锚链，实现锚的起降。1680A. warping head B. fairlead C. wildcat D. capstan16811673 Air blowing from the intake air filter of an operating air compressor indicates _16821673空气压缩机进气滤器有空气吹出，那么说明进气阀损坏1683 A. broken inlet valves

471、B. broken discharge valves1684 C. pulsations in the air distribution system1685 D. overloading of the air distribution system1686 1671 C 1672 C 1673 A1674ff a refrigeration crankcase compressor were short cycling on the low 1675 pressure cutout switch, the cause might be that the _16761674低压控制器频繁动作，

472、造成压缩机起)，停频繁，原因可能是系统中制冷剂缺乏。1677 A. system was overcharged with refrigerant1678 B. system was low on refrigerant1679 C. suction valves were leaking slightly1680 D. relief valve was leaking slightly16811675 Which of the following problems would be the probable cause for the faulty operation of a recipr

473、ocating air compressor suction valve?16821675对于往复式空气压缩机，气缸卸载装置运行不正常会使其吸气阀工作不正常。1683 A. Carbon build up in the piston ring belt.1684 B. Faulty operation of a cylinder un-loader.1685 C. Compressor operation in an area of high relative humidity.1686 D. Lifting of intercooler relief valve.1687 1674 B 16

474、75 B1676In which of the listed hydraulic systems will the installation of an oil1677 cooler be necessary?1676绞缆机液压系统中必须安装油冷器。 A. Constant tension mooring winch system. B. Hatch cover system. C. Watertight door system. D.Internal combustion engine hydraulic starter system.1677 Which of the following

475、problems could cause air to blow out through the inlet air filter of a running compressor?1677见第1673题。 A. Excessive compression in the cylinder. B. A broken intake valve. C. A dirty inlet filter element. D. An improperly adjusted discharge valve.1678A refrigeration unit will tend to short cycle when

476、 operating_16791678制冷装置在低负荷运转时，容易产生压缩机起、停频繁。 A. under heavy loads B. during hot gas defrost C. under light loads D. during starting conditions 1676 A 1677 B 1678 C1679 A vacuum is initially created in a flash type distilling plant by _1679在闪发式造水机中，真空是由喷射器或独立的真空泵产生的。A. the flashing of the feed water

477、B. the condensation of the saltwater feed C. air ejectors, eductors, or a separate vacuum pump D. condensation of the distillate1680 What color is used to indicate the last shot of anchor chain?1680锚链的最后一节是用红色来表示。A. Red B. White C. Blue D. Yellow1681Which of the following problems can result in belo

478、w normal pressure in the 1682 intercooler of an operating low pressure air compressor?1681低压空气压缩机运行时，低压气缸的排出阀泄漏会使中冷器压力偏低。 A. Defective pressure pilot valve. B. Defective receiver relief valve. C. Leaking intake valves on the high pressure cylinder. D. Leaking discharge valves on the low pressure cyl

479、inder 1679 C 1680 A 1681 D 1682If a refrigeration compressor is short cycling on high head pressure, you should 1683 _ 16841682由于排压过高而使制冷压缩机起停频繁，应注意检查冷凝器是否有足够水流。1685 A. purge the condenser if the waterside is dirty B. check for proper water flow through the condenser C. increase the high pressure cu

480、tout setting D. reduce the cooling water flow1683Most pump manufacturers recommended that the discharge piping for centrifugal pumps be _1684 1683绝大多数泵浦制造商建议离心泵排出管的尺寸应比泵的排液喷嘴的尺寸大。1. A. one size larger than the pump discharge nozzle B. the same size as the pump discharge nozzle C. one size smaller th

481、an the pump discharge nozzle D. installed with a short radius elbow at the pump1684 Excessively low air pressure occurring in the intercooler of a reciprocating air compressor is caused by _1.1684往复式空气压缩机的中冷器空气压力过低，通常是由于低压气缸的排出阀漏气引起 A. leaky discharge valves on the LP cylinder B. leaky discharge val

482、ves on the HP cylinder C. insufficient intercooler cooling D. low ambient air pressure 1682 B 1683 A 1684 A1685The refrigeration compressor in a water cooled refrigeration system is short cycling1686 on the high pressure cutout switch. One reason for this could be the _1685水冷式制冷系统中，制冷压缩机由于高压继电器频繁动作而

483、使压缩机起、停频繁，其中一个可能原因是高压继电器没有正确调节。 A. system is low on refrigerant B. high pressure cutout switch is improperly adjusted C. discharge valves are leaking slightly D. discharge valves are leaking excessively1686 In the operation of a flash type evaporator equipped with air ejectors, the air and non-conde

484、nsable gases are evacuated directly from the _1686在装有空气喷射器的闪发式造水机中，空气和不凝性气体直接是从第二级冷凝器中排出 A. first stage flash chamber B. second stage flash chamber C. first stage after condenser D. second stage distilling condenser1687 Most pump manufacturers recommend that the suction piping dimension for centrifu

485、gal pumps be _1687绝大多数泵浦制造商建议离心泵吸人管的尺寸应比泵的吸液喷嘴的尺寸大。 A. one size smaller than the pump suction nozzle B. the same size as the pump suction nozzle C. one size larger than the pump suction nozzle D. installed with a short radius elbow at the pump 1685 B 1686 D 1687 C1688Which of the following statement

486、s about pump operations is NOT a correct 1689 statement ?1690 1688“物质温度低才能泵送这一说法显然不正确。1691A. In order for a fluid to be pumped, a fluid must be made to flow.1692 B. A substance must be cold in order for it to be pumped.1693 C. The kinetic energy imparted by the pump can be used to force a liquid 169

487、4 through a hydraulic system.1695 D. A pump must receive its energy from an external source.16961689 Which of the following precautions should always be carried out in dry dock?16971689船舶坞修时的预防措施包括：液舱之间不得随意泵送；如果已拆卸海底阀门，当船舶重新浮起时应注意检查海底阀门的圆冒是否漏水；在船舶重新浮起前，应确保海底阀箱的滤器已更换等。 1698 A. Liquids should never be

488、 transferred between tanks without1699 consulting the dock master.1700 B. If sea valves have been disassembled, all bonnets must be checked for leakage when the ship is re-floated. all sea chest strainers should be verified as having been replaced.1701 C. Before re-floating, D. All of the above.1702

489、 1688 B 1689 D1703 1690 If an electric motor driven air compressor fails to start, it may be due to a_1690如果电动机驱动的空压机不能启动，可能原因是过载继电器已跳闸。A. leaking discharge valve B. jammed suction valve C. tripped overload relay D. broken discharge un-loader1691Machinery driving fuel oil transfer and fuel oil servi

490、ce pumps must be 1692 fitted with a remote means of stopping the machinery from_1691燃油驳运泵和日用泵的驱动机械应具有遥控的速停装置。1. A. within the space concerned B. outside the space concerned C. the throttle station D. within the fire room 1692 An air compressor can be unloaded at start-up by_1692空气压缩机启动时可通过释放中冷器的压力到大

491、气来实现卸载。 A. holding the discharge valve open B. relieving the intercooler pressure to the atmosphere C. using an enlarged, permanently opened clearance expansion space D. a pre-charged accumulator 1690 C 1691 B 1692 B1693 With regards to fluid flow control, an advantage of pneumatic control 1694 syst

492、ems over electrical control systems is _1693从流量控制的角度看，气动控制比电动控制具有优点。这主要表现在它能在临时的断电情况下还能实现控制。A. practically no limit to the power available for a given system B. no transmission losses C. low energy input D. continued control through temporary electrical power losses 1694 Flexible hose under pressure

493、 in a hydraulic system will _1694液压系统中柔性软管在压力下，将轴向收缩、径向膨胀。A. tend to twist about its long axis B. expand in length and in diameter C. contract in length and expand in diameter D. flex at right angles to the applied pressure 1695 Which of the following statements describes the relationship between fl

494、ash point and ignition temperature?1695着火点总是比闪点高： A. Both are higher than normal burning temperatures. B. The flash point is always higher. C. The ignition temperature is always higher. D. They are not necessarily related. 1693 D 1694 C 1695 C1696 ff a refrigeration compressor will not start, the re

495、ason may be _ 1696制冷系统中制冷剂尸重缺乏，会引起制冷压缩机不能启动。A. the pressure regulating valve is not closing B. an excessive lack of refrigerant in the system C. badly leaking discharge valves D. worn piston ringsThe lowest temperature required to cause serf-sustained combustion of a substance independent of any out

496、side source of ignition is called _1697刁；受外界火源影响，引起物质能持续燃烧的最低温度，称为“着火点。A. explosive range B. flash point C. ignition temperature D. combustion temperature1698 The purpose of the wearing rings used in a centrifugal pump is to _1698离心泵中使用的承磨环用来承受叶轮与泵壳之间的摩擦。 A. prevent an internal explosion in the pump

497、 when it is overheated B. enable a visual inspection of the pump while it is running C. insure a proper alignment of the pump coupling to the driver D. accommodate for friction between the impeller and the casing 1696 B 1697 C 1698 D1699When a refrigeration compressor motor fails to start, the FIRST

498、 thing that 1700 should be checked for is a _ 1699制冷压缩机的电动机不能启动时，首先应检查电路中熔断丝是否熔化。A. loose expansion valve control bulb B. low differential setting on the H.P. cutout C. blown fuse in the motor circuit D. faulty suction pressure regulator1700 Air compressors are equipped with unloading systems for th

499、e purpose of _1700空气压缩机装有卸载装置，用来卸走启动时除了摩擦负荷外的所有负载。 A. removing all but the frictional load during starting B. relieving intercoolers of high temperature buildups C. providing high starting torque in the drive motor D. seating valve plates during compressor shutdown 1699 C 1700 A1701The simplest meth

500、od to use for determining if a centrifugal pump is 1702 operating as designed, is to_1701判断离心泵是否按设计状态运行，最简单的方法是关闭排出阀，观察压力的升高情况。A. closely observe the pump discharge temperature B. close off the discharge valve, and watch for a rise in pressure C. momentarily close off the suction valve, and watch fo

501、r a rise in pressure D. use a clamp on ammeter and compress the reading to past records1702 Which of the following statements concerning butterfly valves is correct?1702对于蝶阀，只要转动手柄14转，就能关闭阀门。 A. Special tools are required for lapping or grinding. B. It is impossible to throttle flow with a butterfly

502、 valve. C. To close the valve, it is only necessary to turn the handle a quarter of a turn. D. The butterfly valve should never be used in a freshwater system. 1701 B 1702 C1703If a large difference exists between the compressor discharge pressure and the pressure corresponding to the existing conde

503、nsing temperature in a refrigeration system, you should_1704 1703制冷系统中，如果压缩机的排压与冷凝温度对应的冷凝压力存在很大的压差，应释放不凝性气体以减少过高的压力。1705A. increase the flow of the cooling water through the condense1706 B. adjust the high pressure cutout to maintain the desired pressure1707 C. open the hot gas bypass temporarily to

504、 reduce capacity 1708 D. purge non-condensable gases to reduce the excess pressure17091704 Pressure in an operating hydraulic system is developed _17101704液压系统工作时的压力是由流体通过系统时的阻力产生的。1711 A. only by the pump as its primary function1712 B. by resistance to the fluid flow through the system1713 C. by th

505、e thermal input to the systems fluid1714 D. solely by the charge applied by the accumulators1715 1703 D 1704 B1705 The accumulation of air and other non-condensable gases in a refrigeration system will_ 1705制冷系统中空气和不凝性气体总是积聚在冷凝器的上半局部。A. cause a loss of the liquid seal B. create a vapor lock in the l

506、iquid receiver C. collect in the condenser D. cause foaming of the oil in the crankcase1706 Which pump installation would require an external source of sealing water?1706舱底离心式污水泵需要灌注外界的液封水。 A. Main circulator pump jacket water cooling. B. Salt water service pump. C. Auxiliary condensate pump. D. Bil

507、ge pump.1707 A lube oil filter can be used to remove most contaminants from lube oil. A contaminant which will remain in the lube oil after filtering is_ 1707滑油滤器能去除滑油中绝大多数污染物。滑油经过净化后仍残留的污染物是燃油。因为酸性物质被滑油中的添加剂中和；沉淀物和水都能在滤器或分油机中被别离。A. acid B. fuel oil C. sediment D. water1708 When installing a hydraul

508、ic hose, which of the following precautions should be taken?1708安装液压软管时，软管不能被扭曲；如果软管承受挤压力，应装套管；软管应有松弛局部(不能拉得太紧)。 A. The hose should not be twisted. B. The hose should be protected with a sleeve if it is subjected to rubbing. C. There should be some slack in the hose. D. All of the above. 1705 C 1706

509、 D 1707 B 1708 D 1709 Air entering an air-cooled refrigeration system is indicated by_1709空冷式制冷系统，如果空气进入到系统，压缩机的排压会偏高。 A. frosting of the liquid line B. higher than normal head pressure C. a clear sight glass D. abnormally cold reefer boxes1710 The presence of bubbles in a refrigeration system liqui

510、d line may_1710制冷系统液相管存在气泡，会携带水分并导致腐蚀。 A. promote refrigerant dehydration B. be absorbed in the receiver C. cause low condensing pressure D. carry moisture and lead to corrosion 1709 B 1710 D1711Dirt should not be allowed to contaminate a grease lubricant because 1712 the _ . .1711。脏物与油脂混合后，会产生很大的磨损

511、作用，因此应防止油脂被脏物污染。A. dirt will cause corrosion of bearing B. bearings will leak oil excessively C. dirt is very abrasive when mixed with grease D. grease will become inflammable1712 The function of a centrifugal pump double volute casing is to _1712离心泵采用双涡壳，其目的是为了减少对叶轮的径向力。A. reduce radial thrust to t

512、he impeller B. double the liquid velocity through the pump when compared to a single volute C. reduce hydraulic end thrust D. provide the effect of multi-staging1713 Differential pressures can be measured with the use of a _1713膜片式压力表、压力传感器和压气计都可测量压差。 A. diaphragm type gage B. pressure transducer C.

513、 manometer D. All of the above 1711 C 1712 A 1713 D 1714Which of the listed statements is a characteristic of the liquid charged power 1715 element used with thermostatic expansion valves?1714热力膨胀阀在正常工作时，其感温包不可能没有液态制冷剂。A. At the designed operating temperature, the liquid refrigerant charge has chang

514、ed to a vapor. B. The liquid refrigerant tends to collect at the bellows or diaphragm and reduces the valve sensitivity. C. The sensing bulb is empty of liquid refrigerant charge at the designed operating temperature. D. The sensing bulb is never emptied of liquid refrigerant under normal operating

515、conditions.1715 The valve best suited for throttling gas or liquid flow in a pipeline is the _1715最适于调节气体或液体流量的阀是球阀。 A. gate valve B. globe valve C. check valve D. plug cock 1714 D 1715 B1716In order to properly remove air from the casing of a centrifugal pump when1717 starting, the pump should have

516、 a _17181716为了在启动时去除离心泵泵壳中的空气，应在涡壳顶部的泵壳上安装透气阀。1719A. positive head B. negative suction head1720 C. mechanical seal1721 D. vent valve attached to the casing at the top of the volute1722Scale accumulation on evaporator heat exchange surfaces _17231717。造水机热交换外表上的水垢会减少热量传递。1724 A. increases brine densit

517、y B. increases distillate salinity1725 C. reduces metal corrosion D. reduces heat transfer17261718 Excessive circulation of the lubricating oil with the refrigerant in a refrigeration system will cause _17271718制冷系统中，过多的滑油随制冷剂循环，会引起蒸发温度升高。1728 A. carbon deposits on the compressor suction valves1729

518、B. the evaporator temperature to increase1730 C. rapid corrosion of the thermal expansion valve1731 D. no operating problems 1732 1716 D 1717 D 1718 B 1719Which of the following centrifugal pump components converts the liquid 1720 kinetic energy of velocity to the potential energy of pressure? 1719离

519、心泵的涡壳将液体的动能转化为压力能。A. Impeller B. Electric motor C. Volute D. Eye1720 Sludge may form in the crankcase of an air conditioning compressor as a result of _1720由于过热和氧化，空调压缩机的曲柄箱会产生沉淀物。A. bubbling refrigerant B. overheating and oxidation C. lowered operating temperatures D. reducing the cloud or flash po

520、int1721 Which of the following statements is correct concerning the flash point of a liquid?1721闪点总是比着火点低。A. It is lower than the ignition temperature. B. It is the temperature at which a substance will spontaneously ignite. C. It is the temperature at which a substance, when ignited, will continue

521、to bum. D. It is the temperature at which the released vapors will fall within the explosive range.1722 If your vessel bums 8 tons of fuel per hour at 15 knots, how many tons per hour will it bum at 18 knots?1722M2=(2)l=(185)X81382(t)。 A. 13.82 tons B. 15.61 tons C. 16.00 tons D. 16.37 tons 1719 C 1

522、720 B 1721 A 1722 A 1723 The percentage of impurities in a specific fuel oil sample is determined by _1723对于给定的燃油油样，杂质的百分比是在实验室的分油机中测定的。A. settling in a fuel tank B. testing in a laboratory centrifuge C. burning in a calorimeter D. testing in a closed cup1724 Which of the listed characteristics can

523、be applied to R- 12 vapor ?1724R12蒸汽是无色无味的。A. It is corrosive. B. It is odorless. C. It is visible as a blue fog. D. It has a distinctive taste.1725 Foaming of the oil in a refrigeration compressor crankcase is caused by _1725制冷压缩机曲柄箱油泡沫是由制冷剂从滑油中蒸发出来所引起。 A. refrigerant boiling out of solution from t

524、he lube oil B. liquid refrigerant flooding the compressor and system C. lube oil viscosity being reduced by refrigerant dilution D. compressor suction pressure suddenly increasing1726 Excessive scale formation in a distilling plant may result from _1726。造水机真空度调节不当，会引起蒸馏装置结垢严重。 A. poor distillate qua

525、lity B. reduced evaporator capacity C. low brine concentration D. improper vacuum regulation 1723 B 1724 B 1725 A 1726 D1727 In a refrigeration system, foaming of the crankcase oil may cause the _ 1727制冷压缩机曲柄箱油泡沫会引起压缩机敲缸。A. expansion valve to overfeed B. compressor to knock C. water regulating valve

526、 to fail D. crankcase drains to plug 1728 The centrifugal pump component responsible for converting the mechanical energy of the liquid being pumped, to that of kinetic energy is the _1728离心泵的叶轮将液体的机械能转化为动能，A. electric motor B. volute C. impeller D. diffusion nozzle 1729 Excessive oil foaming in the

527、 crankcase of a refrigeration compressor can result in _1729制冷压缩机曲柄箱油泡沫过多会引起压缩机轴承过热(；A. overheated compressor beatings B. excess lube oil viscosity C. excess deposits on the compressor piston rings D. wax crystals forming in the lubricant1730 The basic function of the centrifugal pump impeller is to

528、 _1730离心泵叶轮的作用是直接提高液体的速度。 A. directly increase the pressure of the liquid being,pumped B. directly increase the velocity of the liquid being pumped C. convert the potential energy of the liquid to kinetic energy D. separate air from the liquid being pumped 1727 B 1728 C 1729 A 1730 B1731Which of the

529、 following statements is correct concerning a typical shipboard multi-coil1732 refrigeration system?1731制冷系统中，蒸发器中的制冷剂温度直接与制冷剂的压力有关。 A. The liquid receiver functions to collect and remove non-condensable gases. B. A thermostatic expansion valve is used to control refrigerated space temperature. C. R

530、efrigerant temperature in an evaporator is directly related to refrigerant pressure. D. Dehydrators must be used continuously in a refrigeration system.1732 One of the consequences in continuing to operate a centrifugal bilge pump with the discharge valve closed, is that the _1732离心式舱底水泵，在排出阀关闭的情况下持

531、续运转，会引起泵过热。 A. motor overload will open B. relief valve will open C. pump will overheat D. motor will overheat1733 The sudden reduction of pressure occurring within the crankcase of a refrigeration compressor during starting causes the _1733制冷压缩机启动期间，曲柄箱压力突然下降，会引起制冷剂从混合物中蒸发出来 A. sudden evaporation o

532、f wax crystals in the lubricant B. sudden evaporation of entrapped air in the lubricant C. release of refrigerant from the oil/refrigerant mixture D. release of dissolved lubricant from the refrigerant 1731 C 1732 C 1733 C 1734If an operating bilge pump is developing good vacuum, but is unable to di

533、scharge any water, which of the following problems is the most probable cause? 17351734、如果舱底水泵建立起良好的真空度，但不能正常泵水，可能原因是吸口滤器堵塞。1736A. The wearing tings are excessively worn. 1737 B. The suction strainer is clogged.1738 C. The discharge valve is clogged. 1739 D. The shaft is worn.1735 A centrifugal pump

534、 produces flow with a resulting discharge head by energy conversion. It is typical for the energy conversion to follow the order of_1.1735离心泵中能量转换顺序是：机械能到动能再到势能(压力能)。 A. mechanical energy to kinetic energy to potential energy B. mechanical energy to potential energy to kinetic energy C. potential en

535、ergy to mechanical energy to kinetic energy D. kinetic energy to mechanical energy to potential energy 1734 B 1735 A1736 The size of ball and miler bearings can be identified by the _1736球轴承和滚珠轴承的尺寸由制造商的系列号来识别。A. rolling member size B. inner race cone width C manufacturer s numerical code D. outer r

536、ing width 1737 An advantage of a helical gear pump over a simple gear pump is that the helical gear pump is capable of _1737螺旋式齿轮泵与简单齿轮泵相比，优点是能产生更平稳的排量。A. maintaining a steadier speed B. delivering liquids over greater distances C. operating for longer periods of time D. producing a smoother dischar

537、ge flow 1738 Refrigerant is normally sub-cooled in a refrigeration or air conditioning system condenser to _1738在制冷系统的冷凝器中，制冷剂通常处于过冷状态，以防在液相管路产生闪发。 A. maintain adequate coil back pressure B. prohibit flashing in the liquid line C. reduce refrigerant volume in the system D. reduce compressor discharg

538、e line loading 1736 C 1737 D 1738 B 1739The principal purpose of sub-cooling liquid refrigerant prior to its entering 1740 the expansion valve is to _17411739制冷剂在进入膨胀阀前通常处于过冷状态，以防在液相管路产生闪发，从而提高制冷效果。1742A. increase the refrigerating effect, by decreasing the amount of flash gas1743 B. allow the refri

539、gerant to enter the throttling device in a saturated condition1744 C. increase the refrigerating effect by increasing the amount of flash gas1745 D. minimize the temperature drop of the liquid as it passes through the solenoid valve to the outlet side1746 1740 If a bilge pump is able to develop vacu

540、um, but is unable to sufficiently pump out the bilges, you would check for all of the following EXCEPT _17471740如果舱底水泵建立起良好的真空度，但不能正常泵水，不可能的原因是电路问题，因此不需要检查回路切断器。 A. the circuit breaker B. for leaks in the suction piping1748 C. relief valve is not properly seated D. the suction strainer17491741 Sub-c

541、ooling is a method of reducing the temperature of the liquid refrigerant below its _17501741“过冷是指将液态制冷剂的温度降低到其冷凝温度以下。1751 A. freezing point B. floc point 1752 C. condensing temperature D. compression temperature1753 1739 A 1740 A 1741 C 1742Some vessels are equipped with a water lubricated stem tube

542、. When at sea, operating 1743 under normal conditions, the water service valve from the ships saltwater system to the bearing should be _1742一些船舶装有水冷式尾轴管(铁梨木轴承尾轴管)，在海上正常航行状态下，船舶海水系统中向轴承供水的海水阀应关闭，只允许少许海水漏人。A. closed, and no leakage permitted across the shaft packing B. closed, and only slight leakage

543、 permitted across the shaft packing C. open, and no leakage permitted across the shaft packing D. open, and only slight leakage permitted across the shaft packing1743 Under normal conditions, the refrigerant enters the compressor in an operating refrigeration system as a _1743制冷系统工作时，进入到压缩机的制冷剂处于过热状

544、态。A. liquid B. dry saturated gas C. wet saturated gas D. superheated vapor1744 An excessive amount of water is prevented from entering a vessel using a water lubricated stem tube bearing by the use of the _1744。水冷式尾轴承的尾轴管，使用盘根以防过多的海水进人到船舶。A. propeller hub B. lignum vitae C. shaft packing D. labyrint

545、h seal1745 Refrigerant enters the condenser as a _1745。制冷系统工作时，进入到冷凝器的制冷剂是高压蒸汽。 A. high pressure liquid B. low pressure vapor C. high pressure vapor D. low pressure liquid 1742 B 1743 D 1744 C 1745 C1746If the pump for a hydraulic anchor windlass is overheating, the cause 1747 may be _1746如果液压锚机的油泵过

546、热，原因可能是油泵的排出压力过高。A. excessive drive motor speed B. excessive pump discharge pressure C. too low of a tilting box angle D. insufficient drive motor speed1747 An independent bilge suction is required for _1747机器处所的舱底吸口是独立式的。A. ballast tanks B. sludge tanks C. machinery space bilges D. cargo hold bilge

547、s1748 In a flash distilling unit, evaporator feed (seawater) first absorbs heat in the _1748在闪发式造水机中，给水(海水)首先从淡水冷却器中吸收热量。 A. vapor feed heater B. air ejector condenser C. saltwater heater D. distillate cooler1749 The function of lubricating oil is to _1749滑汕的作用是减少运动部件之间的摩擦。 A. reduce friction betwee

548、n moving surfaces B. provide even distribution of bearing wear C. reduce the accumulation of harmful detergents D. maintain a constant oil temperature output at each bearing 1746 B 1747 C 1748 D 1749 A1750 A dirty intercooler on the ship service air compressor will result in _ 1750船用空压机的中冷器脏了，会导致功率消

549、耗增大。A. decreased compression ratio B. higher than normal power consumption C. un-loader malfunction D. water in the lubricating oil1751Which of the listed conditions will cause the feed water, that has not flashed 1752 to vapor in the _ first-stage of a flash evaporator, to flow into the second-stag

550、e71751在两级闪发式造水机中，由于第二级真空度较高，在第一级中未闪发的海水能流向第二级。A. Gravity siphon effect. B. Higher vacuum in the second-stage. C. Difference in brine density between first and second stages. D.Lower pressure in first-stage.1752 Under normal operating conditions, the highest temperature and pressure conditions existi

551、ng in a flash-type evaporator will occur in the _1752在闪发式造水机运行过程中，海水加热器处的压力和温度最高。 A. first stage B. second stage C. distillate cooler D. salt water feed heater 1750 B 1751 B 1752 D 1753 A dirty intercooler on an air compressor will cause _ 1753船用空压机的中冷器脏了，会导致马达电流增大，功率消耗增大。A. damage to the un-loader

552、operating diaphragm B. an increase in current flow to the motor C. high pressure in the receiver and filter D. an excessive consumption of crankcase oil 1754 The effect of high vapor superheat in a refrigeration system, is a/an _1754制冷系统中，制冷剂蒸汽过冷度过高，会减少压缩机的排量。A. increased capacity of the compressor

553、B. more efficient operation of the thermal expansion valve C. decreased capacity of the compressor D. loss of receiver capacity 1755 Excessive lube oil consumption by a reciprocating air compressor can be caused by _1755对于往复式空压机，滑油油位过高会引起油耗增加。 A. using a slightly dirty air filter B. using oil having

554、 an excessive viscosity C. intercooler or after-cooler leaks D. carrying the oil level higher than normal 1753 B 1754 C 1755 D1756In which of the listed refrigeration system components does superheating 1757 of the refrigerant take place?1756在制冷系统的蒸发器中，制冷剂发生过热。A. Expansion valve B. Evaporator C. Dri

555、er D. Receiver1757 The vacuum maintained in the salt water feed heater shell of a flash-type evaporator is generally accomplished by_1757在闪发式造水机中，海水加热器的真空一般是通过从第一级闪发室引出来实现。A. a separate air ejector unit B. a direct unimpeded connection between second stage and salt water feed heater C. either by vac

556、uum drag or an external line from the first stage via a fixed orifice D. the fixed orifice provided in the steam supply line1758 In a refrigeration system, the amount of refrigerant admitted to the evaporator is directly related to_1758在制冷系统中，允许进入到蒸发器的制冷剂流量直接与其过热度有关。A. the compressor discharge press

557、ure B. condenser cooling water temperature C. the solenoid valve differential pressure D. the superheat of the refrigerant in the tail coil 1756 B 1757 C 1758 D1759 The refrigerant gas returning to the compressor should be _1759。回到压缩机的制冷剂蒸汽应该处于过热状态。A. superheated B. saturated C. dense D. flooded1760

558、 If the electric motor driving an air compressor fails to start, the cause may 1761 be a _1760、如果空压机的电动机不能启动，原因可能是断路器跳闸。 A. leaking unloader B. tripped circuit breaker C. control line leak D. defective pop valve1761 The low pressure side of a refrigeration system is considered to exist from the _176

559、1制冷系统中的低压侧是从膨胀阀到压缩机。A. expansion valve to the compressor B. receiver to the expansion coil C. expansion valve to the evaporator D. condenser to the expansion valve1762 The component of a refrigerating system in which the refrigerant vaporizes and absorbs heat is known as the _1762制冷剂在蒸发器中蒸发并吸收热量。 A.

560、 condenser B. vapor generator C. accumulator D. evaporator 1759 A 1760 B 1761 A 1762 D1763In which of the areas listed would you expect to find the highest salt 1764 concentration in a flash evaporator?1763在两级闪发式造水机中，第二级海水箱中的盐度最高。 A. Distiller air ejector cooling medium. B. Saltwater heater discharg

561、e. C. First-stage internal feed box. D. Second-stage internal feed box.1764 An AC synchronous transmission type remote steering control system consists of a_1764舵机遥控系统中有发送器和接收器。A. transmitter at the steering station and a receiver at the steering engine B. reversible motor at the steering station ge

562、ared to the steering pumps C. small induction motor on the bridge which controls the rudder through pulleys D. variable displacement hydraulic pump driven by a reversible DC motor1765 To operate a centrifugal fire pump at reduced capacity, you should_1765离心式消防泵在低排量工作时，应关小排出阀 A. readjust the relief v

563、alve B. throttle the suction line C. throttle the discharge valve D. open the priming line 1763 D 1764 A 1765 C 1766Which of the following best describes the thermodynamic effect on the1767 pressure and volume relationship with regards to saturated gases?l766对于饱和气体而言，压力减少，体积增大。A. As pressure decreas

564、es, volume increases B. As volume increases, pressure increases C. As volume decreases, pressure decreases D. As pressure increases, volume increases1767 The discharge rate or capacity of a centrifugal pump will vary directly as the_1767离心泵的排量随叶轮直径的改变而变化。A. change in the impeller diameter B. square

565、of the impeller radius C. cube of the impeller diameter D. impeller efficiency for large changes in its size1768 When operating with a negative suction head, which of the following types of pumps will require priming?l768离心泵不具有干吸能力，运行前需要灌水。 A. Reciprocating B. Centrifugal C. Rotary D. Gear 1766 A 17

566、67 A 1768 B1769The refrigerant leaves the evaporator of a refrigeration system as a low 1770 pressure_ 1771 l769制冷系统中，蒸发器出口是低压过热蒸汽。 1772A. sub-cooled liquid B. high temperature liquid C. oil saturated liquid D. superheated vapor1770 Reduced capacity, accompanied by vibration and noise at the suction

567、 of a centrifugal pump is a result of_1.1770离心泵排量下降，吸入口伴有振动和噪声，原因是泵发生气蚀现象。2.A. cavitation B. water hammer C. fluid friction D. steam knock1771In order to accurately measure very low pressures, which of the instruments listed should be used?1.1771压气计可精确测量很低的压力。2.A. Compound gage B. Bourdon tube C. Ma

568、nometer D. Deadweight gage1772 ff a centrifugal bilge pump were continually operated with the discharge valve closed the_1.1772离心式舱底水泵，在排出阀关闭的情况下持续运转，会引起泵过热。2.A. motor overload would open B. relief valve would open C. pump would eventually overheat D. motor would overheat1773 Which of the listed pre

569、ssure control valves would be used to establish the maximum operating pressure of a hydraulic system.?1. 1773液压系统中，压力释放阀用来建立起最大的工作压力。 A. Pressure-reducing valve. B. Unloading valve. C. Counterbalance valve. D. Pressure-relief valve. 1769 D 1770 A 1771 C 1772 C 1773 D 1774 The temperature of a refrig

570、erant gas is the highest_ 1774制冷系统中，压缩机排出口的制冷剂气体温度最高。A. at the compressor discharge B. at the compressor suction C. in the expansion valve D. in the receiver1775Condensate formed within the first-effect tu nest of a double-effect, low 1776 pressure evaporator, is removed by a_1775在双效低压蒸发器中，第一级管子内的凝水

571、是由排液泵来排除。A. series of baffles B. crossover pipe C. condensate separator D. drain pump1776 A centrifugal pump attempting to develop flow against a closed discharge valve has a/an_1776、排出阀关闭时，离心泵的排量为零。A. capacity of 0% B. efficiency of 100% C. internal slippage of 0% D. shut off horsepower rating of 1

572、00%1777 A compound gage is used to measure_、组合式压力表可测量压力和真空度。 A. temperature and pressure B. humidity and temperature C. pressure and vacuum D. pressure and humidity 1774 A 1775 D 1776 A 1777 C 1778Which of the listed components is considered to separate the high pressure 1779 side of a refrigeration

573、 cycle from the low pressure side of the cycle? 1778在制冷系统中，压缩机和膨胀阀将系统分成低压侧和高压侧。A. The condenser and the expansion valve. B. The king valve and the solenoid valve. C. The compressor and the expansion valve. D. The condenser and the solenoid valve.1779 Which of the listed refrigeration system componen

574、ts keeps the refrigerant circulating through the system?1779在制冷系统中，压缩机用来保持制冷剂在系统中循环。A. Expansion valve B. Condenser C. Evaporator D. Compressor1780 Which of the valves listed is NOT considered to be a hydraulic system directional control valve?1780卸载阀不属于液压系统中的方向控制阀。 A. Spring-centered valve. B. Unlo

575、ading valve. C. Three-position valve. D. Two-position valve. 1778 C 1779 D 1780 B1781Excessive oil foaming in the crankcase of a refrigeration compressor at start up1782 can cause _1781制冷压缩机启动时曲柄箱油泡沫过多，会引起压缩机因润滑不良而损坏。A. compressor damage from improper lubrication B. refrigerant absorption by the lub

576、ricant C. increased viscosity in the lubricant D. carbon deposit on the compressor suction valves1782 Which of the listed statements is correct concerning the starting of centrifugal pumps?1782。离心泵启动时，排出阀应关闭，即封闭启动。 A. They should always be started with the discharge valve closed. B. They should alwa

577、ys be started with the discharge valve opened. C. A priming pump is always required to flood the impeller suction. D. They should always be started with the sealing line valves closed.1783A compound gage is typically installed on the _1783组合式压力表一般安装在舱底水泵的吸人侧。 A. suction side of a bilge pump B. exhau

578、st manifold of an auxiliary diesel C. discharge line from an air compressor D. chemical feed tank of an evaporator 1781 A 1782 A 1783 A 1784 When refrigerant leaves the receiver, it flows next on to the_1784在制冷系统中，制冷剂离开贮液器后流向过滤器。A. evaporator coils B. liquid strainer C. compressor D. condenser1785 T

579、he type of gage most commonly used to measure pressure is the_1785压力测量通常使用波登管式压力表。A. bimetallic type B. diaphragm type C. bourdon tube type D. resistance-temperature type1786 Which of the following statements is true concerning centrifugal pumps?1786对于离心泵，叶轮的旋转给液体施加能量，从而实现流体泵送。 A. They are particula

580、rly suited for pumping high viscosity fluids. B. They are started with the discharge valve opened. C. The flow of liquid is developed by imparting energy due to the rotation of an impeller. D. They are always mounted in a horizontal position.1787 Refrigerant is circulated through a refrigeration sys

581、tem by the _. .1787在制冷系统中，压缩机用来保持制冷剂在系统中循环。 A. compressor B. condenser C. expansion valve D. evaporator 1784 B 1785 C 1786 C 1787 A1788The temperature of the refrigerant in the evaporator coil depends mostly 1789 upon the _ 1788制冷剂在蒸发盘管中的温度主要取决于蒸发器的压力。A. refrigerant pressure in the evaporator B. coo

582、ling water temperature to the condenser C. heat load in the refrigerator compartment D. solenoid valve in the liquid line1789 Which of the following types of hydraulic pumps would be used in a steering system?1789在舵机系统中，可采用轴向或径向柱塞泵。A. Lobe B. Screw C. Radial piston D. Volute1790 An increase in the h

583、eat load to a refrigeration system will cause _1790制冷系统热负荷增加会引起吸人温度增加。 A. the suction pressure to decrease B. the suction temperature to increase C. increased ice formation on the evaporator coil D. excessive short cycling of the compressor 1788 A 1789 C 1790 B1791 The discharge head of a centrifuga

584、l pump will vary directly with the 1791离心泵的排量与叶轮直径的平方成正比。A. change in impeller diameter B. square of the impeller diameter C. cube of the impeller diameter D. impeller efficiency for large changes in the size of the impeller1792To thoroughly pump out the bilges using a horizontally mounted centrifug

585、al 1793 pump, the _1792使用卧式离心泵彻底排干舱底水，离心泵必须要灌水。A. pump must always be primed B. volute must impart a radial and rotary motion of the water suction side C. connection must guide the liquid to the lantern rings D. stuffing box should not be allowed any water leakage1793Which of the following terms wou

586、ld best describe the temperature at which a liquid boils at a given pressure?1793饱和温度是指在给定的压力下液体蒸发的温度。 A. Degree of saturation. B. Saturation temperature. C. Superheated temperature. D. Degree of superheat. 1791 B 1792 A 1793 B1794 A refrigerant with oil in solution has a _ 1794在给定的压力下，含有油的制冷剂比纯洁的制冷

587、剂蒸发温度要高。A. higher boiling temperature for a given pressure than does a pure refrigerant B. lower boiling temperature for a given pressure than does a pure refrigerant C. boiling pressure equal to that of a pure refrigerant at a given pressure D. boiling point will not be affected by entrained oilMac

588、hinery operating features are designed to help conserve energy. Which of the following results will not contribute to energy conservation?1795“冷却器出口温度升高不涉及能量转换。A. Reduction of friction. B. Insulation of hot surfaces. C. Lubrication of moving parts. D. Elevation of cooler outlet temperatures.On which

589、 of the following heated surfaces of a flash type evaporator would you be more likely to find soft scale formation?1796在闪发式造水机中，海水力口热器的管壁会产生水垢。 A. Feed-water heater internal tube surfaces. B. Internal distillate cooler tubes. C. Flash chamber vertical surfaces. D. Distilling condenser tubes. 1794 A

590、1795 D 1796 A1797 Strainers are commonly used in hydraulic systems to_1797液压系统中使用滤器来防止固体颗粒进人到液压泵。 A. protect the pmnp from fine soluble contaminants B. prevent solid particles from entering the pmnp C. prevent solid particles from entering the filter D. protect the directional control valves1798Exce

591、ssive oil foaming in the crankcase of a refrigeration compressor is1799 most likely to occur when the compressor _1798制冷装置很长一段时间停用后启动，压缩机的曲柄箱油会产生过多的泡沫。A. has mn continuously for a long period B. suction pressure is below normal C. oil level is below normal D. starts after a long idle period1799 In a

592、 compression refrigeration cycle, the temperature of the liquid refrigerant experiences its greatest decrease in the_1799在压缩式制冷循环中，液态制冷剂的温度在膨胀阀处下降最大 A. evaporator B. compressor C. expansion valve D. condenser 1797 B 1798 D 1799 C1800 Which of the following statements concerning energy is correct?180

593、0“宇宙中总能量保持不变。是正确的。即能量守恒定律。 A. Energy can be created or destroyed. B. Energy may not be transformed. C. The total quantity of energy in the universe is always the same. D. None of the above.By which of the following means is force efficiently provided to vary the pitch of the blades on a modem contro

594、llable pitch propeller?1801调距桨一般采用液压调距机构。 A. Hydraulic B. Mechanical C. Pneumatic D. Electrical1802 Which of the listed statements is correct concerning refrigeration systems?180225t的制冷系统与在24h之内溶化25t冰具有同样的冷却效果 A. Dehydrators must be used continuously in a refrigeration system. B. A 25 ton refrigerat

595、ion system has the same cooling effect as melting 25 tons of ice in 24 hours. C. A thermostatic expansion valve is used to control refrigerated space temperature. D. The liquid receiver functions to collect and remove non- condensable gases. 1800 C 1801 A 1802 B1803When the vessels steering wheel on

596、 the navigation bridge is turned, the 1804 difference existing between the position of the wheel and that of the redder is known as _ 1803当在驾驶台转动舵轮时，舵轮的位置与舵的位置之间的差，称为偏差信号。A. proportional band B. the error signal C. the reset signal D. feedback1804 Which of the conditions listed represents the greate

597、st effect of excess frost accumulation on the evaporator coils?1804蒸发盘管严重结霜将降低制冷装置的效率。A. Keeps the refrigerated space cooler. B. Reduces the efficiency of the plant. C. Takes the load off the compressor. D. Has no affect on the system.1805 In the design of hydraulic piping and equipment consideratio

598、n is given to minimize turbulence in the hydraulic fluid, as this will cause _1805在液压管系和设备的设计中，应考虑尽量减少液压流体的扰动，因为流体扰动将会引起能量损失。 A. molecular fluid vibration B. energy losses C. wide pressure variations D. mechanical damage to control valves 1803 B 1804 B 1805 B1806If a refrigeration compressor is runn

599、ing continuously without lowering1807 the temperature in the refrigerated space, the trouble may be_18081806如果制冷压缩机持续运转但不能实现降温，可能原因是制冷剂缺乏。1809A. a shortage of compressor oil B. warm food in the refrigerator1810 C. excessive condenser cooling water D. a shortage of refrigerant18111807 Which of the va

600、lves listed should be used either in the fully opened or the fully closed position?18121807门阀只能在全开或全关状态下工作。1813A. A gate valve B. A globe valve C. Any check valve D. Any needle valve18141808 Which of the following modes of heat transfer does NOT require any _1815 physical contact between a warmer an

601、d a cooler substance?18161808辐射传热不需要物体的直接接触就能实现。1817A. Radiation B. Conduction C. Natural convection D. All of the above1818A gate valve installed in a pipeline should be_18191809，门阀只能在全开或全关状态下工作。1820 A. used in either the fully closed or fully opened position1821 B. installed with the stem down C.

602、used for steam service only1822 D. used to throttle or regulate the flow of liquid1823 1806 D 1807 A 1808 A 1809 A1810The movement of heat within a fluid, caused by the application of thermal 1811 energy, is called _1812 1810，山热能的作用引起流体内部热量的运动，称为对流。1813A. radiation B. conduction C. convection D. con

603、do-radiation18141811 Air compressor cylinder un-loaders enable the compressor to _18151811空压机的卸载装置使压缩机在空气压缩前启动并到达一定转速、1816A. vary their speed according to temperature and load1817 B. start and come up to speed before air compression begins1818 C. change speed according to overload demands1819 D. red

604、uce compressed air charge density18201812 Which of the conditions listed will cause a refrigeration compressor to run constantly without simultaneously decreasing the temperature in the refrigerated space?18211812如果制冷压缩机持续运转但不能实现降温，可能原因是制冷刹缺乏1822 A. Shortage of refrigerant oil. B. Slight shortage of

605、 refrigerant.1823 C. Excessive condenser cooling water flow.1824 D. Faulty expansion valve.1825 1810 C 1811 B 1812 B 1813 Which of the listed methods of heat transfer takes place when two substances of different temperatures are in physical contact with each other?1813两种不同温度的物体，通过直接接触实现热量传递的过程是热传导。A

606、. Radiation B. Conduction C. Convection D. Each of the aboveThe unloading system on an air compressor will_1814空气压缩机的卸载设备能卸走启动时除了摩擦负荷外的所有负载。A. increase compressor discharge pressure on demand B. increase compressor operating speed as necessary C. allow the motor to turn the compressor opposed only b

607、y friction D. reduce the compressor frictional load when starting1815 A warmer than normal compressor suction line might be caused by_1815压缩机吸人管温度过高通常是由制冷剂缺乏引起， A. insufficient lubrication B. insufficient refrigerant C. excess refrigerant D. excessive opening of the expansion valve 1813 B 1814 C 181

608、5 B1816Which of the following conditions must exist for heat to flow from one 1817 object to another71818 1816两种物体之间必须具有温度差，才能实现热量传递：1819A. The two objects must be in physical contact.1820 B. The two objects must be the same size.1821 C. There must be an existing temperature differential.1822 D. The

609、re must be an existing weight differential.18231817 In the refrigeration system, a shortage of refrigerant is indicated by_18241817制冷系统中制冷剂缺乏通常表现为示液镜中有气泡；1825 A. the compressor short cycling on high pressure cut out switch1826 B. high suction pressure1827 C. high head pressure1828 D. bubbles in the

610、sight glass1829 1816 C 1817 D1818Condensate must be drained from the intercooler and after-coolers of an air 1819 compressor because _18201819、如果制冷系统中制冷剂缺乏，将会导致压缩叽持续运转、1821 A. the cooling effect of the condensate reduces the compressor s efficiency1822 B. a danger of explosion exists whenever water

611、is present in a compressor1823 C. water causes erratic operation of pneumatic components1824 D. the volumetric capacity of the first stage is reduced if water remains18251819 If a refrigeration system were short of refrigerant, the condition would result in _18261820、如果舵机系统液压油中含有空气，舵将反响迟钝。1827 A. co

612、ntinuous running of the compressor B. high suction pressure1828 C. high discharge pressure1829 D, short cycling of the compressor on the water failure switch1830 1820 When air becomes trapped in the hydraulic fluid of a steering system, the _18311821往复式蒸汽泵停用很长一段时间后重新启动前，应将汽缸排干。1832 A. redder will re

613、spond sluggishly B. hydraulic rams will over-speed1833 C. sight glass will show bubbles D. mm relief valves will lift1834 1818 C 1819 A 1820 A 1821 Before starting a reciprocating, steam-driven pump that has been idle for a period of time, you should _ 1821往复式蒸汽泵停用很长一段时间后重新启动前，应将汽缸排干。A. open the ste

614、am line root valve B. drain the steam cylinder C. close the steam cylinder drains D. open the liquid cylinder drains1822The air charge leaving an intercooler, or after-cooler of an air compressor 1823 can be expected to be _1822经过空压机中冷器或后冷器的空气应处在露点或露点以下。A. superheated B. super-ccled C. at or below t

615、he dew point D. All of the above1823 Noise in a refrigeration compressor can be caused by _1823轴承、活塞销磨损；液击；过多滑油循环等都会造成制冷压缩机噪声。A. worn bearings and piston pins B. slugging due to flooding back C. too much oil in circulation D. All of the above1824 Thermal energy in transition is also referred to as _

616、1824热能是以热量传递方式进行的。 A. heat B. power C. horsepower D. foot-pound 1821 B 1822 C 1823 D 1824 A1825 Flooding back is a condition where the liquid refrigerant _ 1825。液态制冷剂从吸人管到达压缩机，便产生“液击。 A. vaporizes in the condenser B. reaches the compressor through the suction line C. flashes in the liquid line D. co

617、ndenses in the receiver1826 The energy associated with molecules is known as _1826与分子运动有关的能量称为热能。 A. kinetic energy B. potential energy C. mechanical energy D. thermal energy1827 Overgreasing of ball bearings installed on pumps will result in _1827安装在泵浦中的球轴承，如果加注油脂过多，会导致轴承过热。A. smoother pump operati

618、on B. overheating of the bearing C. reduced corrosion in the bearing D. increased pump capacity1828 Air trapped in the hydraulic fluid of a steering system should be indicated by _1828如果舵机系统液压油中含有空气，舵将反响迟钝。 A. the pump over-speeding B. an improper rudder response C. bubbles in the sight glass D. ram

619、 relief valves lifting 1825 B 1826 D 1827 B 1828 B1829While troubleshooting a refrigeration system for low head pressure,1830 liquid refrigerant flooding back from the evaporator is determined to be the cause. It may be necessary to _ 1829由于液态制冷剂流回到蒸发器，造成制冷系统吸人压力低。此时，应改变膨胀阀的调节 A. change the expansio

620、n valve adjustment B. readjust the water regulating valve to increase the flow of water C. purge air from the condenser D. clean the waterside of the condenserl830 On small , low pressure , air compressors , the cylinders are usually lubricated by the _1830在小型、低压空气压缩机中，气缸通常通过飞溅的方法来润滑。 A. splash meth

621、od B. mechanical force feed lubricators C. detached sump method D. internal cooling passages in the crankshafts and connecting rods1831 To correct the condition of slugging and flooding back in a refrigeration system, it may be necessary to _1831。通过调节热力膨胀阀，能纠正制冷系统产生液击现象。 A. re-adjust the discharge p

622、ressure B. clean the expansion valve screen C. add refrigerant D. adjust the expansion valve 1829 A 1830 A 1831 D1832 Power is defined as the _1832功率可定义为“作功的速率。A. rate of doing work B. amount of force needed to overcome friction C. amount of work accomplished D. distance through which an object is m

623、ovedWhich of the listed devices would be installed at a control system air pressure reducing station?1833空气控制系统的减压装置中安装了分水器。A. Moisture separator B. Vacuum breaker C. Lubricator D. Non-return valve1834 Air line lubricators are used in compressed air systems to lubricate _1834压缩空气系统中的注油器用来润滑气动的工具和设备。

624、 A. the suction and discharge valves B. tools and equipment served by compressed air C. air line reducing valves D. all of the above 1832 A 1833 A 1834 B 1835 When a vessel is in dry-dock, the vessels engineers should _1835当船舶在坞修时，轮机员应检查螺旋桨的状况。A. examine the condition of the propeller B. chip and pa

625、int all hull protection zincs C. install new docking plugs in all cofferdams D. inspect the hull for hogging or sagging 1836 If you change from a low pour point lubricant to a high pour point lubricant in a refrigeration system, _1836在制冷系统中，把低倾点的滑油换成高倾点的滑油，滑油将会在蒸发器中冻结。A. compressor lubrication will

626、be improved B. oil will not leave the crankcase C. compressor valves will be damaged D. oil may congeal in the evaporator 1837 Mechanical energy in transition is referred to as _1837机械能是以功的形式转变的。 A. horsepower B. work C. heat D. velocity 1835 A 1836 D 1837 B1838 Badly leaking refrigeration compresso

627、r discharge valves will cause _1838制冷压缩机排出阀严重漏气，将引起压缩机持续运转。A. overfeeding of the expansion valve B. damage to the condenser C. constant running of the compressor D. flooding of the receiver1839 In a refrigeration system equipped with a reciprocating compressor and a water cooled condensing unit, lea

628、king compressor discharge valves will result in _1839制冷压缩机排出阀严重漏气，将引起压缩机排出压力偏低。A. refrigerant flooding of the compressor B. low suction pressure C. noisy compressor operation D. low head pressure1840 The delivery rate of an axial-piston hydraulic pump is controlled by varying the position of the _18

629、40轴向液压泵的排量是通过改变倾斜盘的位置来控制。 A. sliding block B. pintle C. reaction ring D. tilting box or swash plate 1838 C 1839 D 1840 D1841Which of the following terms could be applied to the simple definition1842 the energy of motion ?1843 1841“动能可简单地定义为“运动的能量。 1844A. Electrical energy B. Thermal energy C. Potent

630、ial energy D. Kinetic energy18451842 ff the discharge valves on a refrigeration compressor are leaking badly, the compressor should_18461842。制冷压缩机排出阀严重漏气，将引起压缩机持续运转。1847A. run continuously B. not start1848 C. have high discharge pressure1849 D. short cycle on the high pressure switch18501843 Increas

631、ing the speed of a centrifugal pump will result in an increase in its capacity. Another means of increasing the capacity of a centrifugal pump is to increase the_18511843提高离心泵的排量一般有两种方法：提高转速；增大叶轮的直径1852 A. diameter of the discharge piping, with all other factors remaining the same1853 B. diameter of

632、 the suction piping, with all other factors remaining the same1854 C. width of the impeller only1855 D. diameter of the impeller1856 1841 D 1842 A 1843 D1844Excessive air leakage into the suction side of a centrifugal pump would be 1845 indicated by which of the following operational problems?1844过多

633、的空气漏人到离心泵的吸人侧，离心泵的排量将逐渐减少。A. The pump delivers full capacity when started, but gradually slackens off to an abnormally low flow. B. The pump packing gland overheats after short operating periods. C. The motor over-current protective device continually shuts the pump down. D. Pounding noises can be h

634、eard at the pump suction chest.1845 While inspecting the steering system at sea, you should check for _1845在海上检查舵机系统时，应注意检查系统的漏泄情况。A. air bubbles in the sight glass B. any leaks in the system C. over-travel in the rudder angle indicator D. lost motion in the rams1846Which of the following forms of e

635、nergy is demonstrated through the process of combustion?1846燃烧过程中释放化学能。 A. Chemical energy B. Mechanical energy C. Thermal energy D. Electrical energy 1844 A 1845 B 1846 A1847The capacity of a centrifugal pump can be increased by the installation of 1848 .a larger diameter impeller. Another means of

636、 increasing the pump capacity is to _18491847提高离心泵的排量一般有两种方法：提高转速；增大叶轮的直径。1850。1851 A. increase speed1852 B. increase the size of the cardent assembly1853 C. reduce wearing ring clearances1854 D. change the pump to a close coupled arrangement18551848 A spur gear pump should be operated with the disc

637、harge valves _18561848齿轮泵启动时应将排出阀全部翻开。1857A. slightly opened B. throttled C. fully opened D. halfway opened18581849 The oil in a cargo winch gear box should be sampled periodically to _18591849起货机齿轮箱油应定期取样，确保不被污染1860 A. prevent the gear box from leaking1861 B. prevent the oil from becoming inflammab

638、le1862 C. make sure it has not become contaminated1863 D. make sure the motor bearings are lubricated1864 1847 A 1848 C 1849 C1850 When the steering gear is in operation, you should _ 1850在舵机工作过程中，应注意检查是否有过多的油从撞杆处泄漏。A. check hydraulic oil levels every hour B. cheek the rams for overheating C. cheek

639、for excessive oil leakage from rams D. drain water from telemotor cylinders each watch1851An excessive charge of refrigerant in an air-cooled refrigeration system can cause _1851空气冷却式制冷系统，制冷剂充注过多，将使压缩机的排出压力偏高。A. oil foaming in the compressor B. higher than normal suction and discharge pressures with

640、 a higher box temperature C. higher than normal discharge pressure with a normal box temperature D. the compressor to run continuously 1852 The output volume of a positive fixed-displacement pump can be changed only by _ 1852。容积式泵的排量只能通过改变泵的转速来改变。 A. changing the angle of the tilting plate B. changi

641、ng the speed of the pump C. moving the slide block and rotor D. moving the Shaft trunnion block 1850 C 1851 C 1852 B1853If you are given the job of adding hydraulic fluid to a mooring winch, and 1854 are not certain as to the type of fluid to use, you should _ 1853给绞缆机加注润滑油时，如果对使用的液压油种类不清楚时应查阅制造商的说明

642、书。 A. add fluid that is the same color as the fluid in the reservoir B. add turbine oil because it is always a good substitute C. add any oil that has the same viscosity as the hydraulic fluid D. check the winch manufacturers instruction book 1854 A gradual decrease in the discharge pressure of an o

643、perating hydraulic pump can be caused by _ 1854液压泵的排出压力逐渐下降，可能是由于油箱中的滤器堵塞引起。 A. the four-way control valve failing to shift B. the bleeder valve sticking in the open position C. cold hydraulic fluid D. a clogged air vent filter on the oil reservoir 1853 D 1854 D1855The rate of heat transfer from a h

644、ot region to a cold region is affected most by the _ 1856 1855从高温区到低温区的热量传递速度受两者的温差影响最大。1857 A. size of the heat sink B. temperature difference between the regions C. size of the heat source D. total heat of the system1856 Who is responsible for ensuring that someone is assigned to close the waterti

645、ght doors in an emergency?1.1856在应急情况下，船长负责指派人员关闭水密门。2.A. Maritime Safety Administration. B. Master of the vessel. C. Chief Engineer. D. Chief Mate.1857 Which of the following statements is correct concerning heat transfer?1.1857从高温区到低温区的热量传递速度受两者的温差影口向最大。 A. Heat is given off from a high temperatur

646、e laegion known as a heat sink. B. Heat transfer rate is affected most by the size of the heat sink involved. C. Heat transfer rate is affected most by the temperature difference between the heat source and the heat sink. D. Heat transfer by radiation will occur only by mass motion of a fluid substa

647、nce. 1855 B 1856 B 1857 C1858When a refrigeration compressor has developed a high head pressure as a result of 1859 a refrigerant overcharge, you should _ 18601858制冷剂充注过多，将使压缩机的排出压力偏高。此时，应释放系统中的局部制冷剂。1861A. increase the amount of cooling water to the condenser1862 B. decrease the amount of cooling w

648、ater to the condenser1863 C. add more refrigerant to the system1864 D. remove some refrigerant from the system18651859 On tank vessels equipped with power operated cargo tank valves, the type of power operator most commonly used is _ 18661859，油轮上，货油舱的阀门通常是液压驱动的。1867 A. hydraulic B. electric C. steam

649、 D. diesel18681860 If the viscosity of the liquid being transferred remains constant as the discharge pressure increases, the rotary pump18691860对于旋涡泵，如果随着排出压力的提高，被泵送的液体粘度保持恒定，泵的排量将下降。 1870 A. capacity will increase B. capacity will decrease1871 C. suction pressure will increase D. suction pressure

650、will decrease1872 1858 D 1859 A 1860 B1861If the suction pressure at the refrigeration compressor is below normal, the 1862 cause can be _ 18631861制冷压缩机吸人压力偏低，原因可能是吸人滤器堵塞。1864A. refrigerant overcharge B. overfeeding by the expansion valve1865 C. a restricted suction strainer1866 D. due to short cycl

651、ing of the compressor18671862 A salinity indicator is used to determine the _ 18681862盐度指示仪用来判断被海水污染的区域。1869 A, cause of salt contamination B. location of salt water contamination1870 C. chemical makeup of feed-water1871 D. level of alkalinity in condensate18721863 If the relief valve on the dischar

652、ge side of a hydmtdic pump lifts, the cause could be _ 18731863液压泵排出侧的释放阀翻开，原因可能是液压泵和液压马达之间的管路堵塞。1874 A. a low load on the unit B. a clogged pump suction strainer1875 C. a blockage in the line between the pump and hydraulic motor1876 D. the hydraulic motor turning too fast1877 1861 C 1862 B 1863 C18

653、64The rate of heat transfer between the hot and cold fluids passing through 1865 a shell-and-tube type heat exchanger will _ 1866 1864经过壳管式热交换器的热、冷两种流体之间的热交换速度在各截面都是不同的。1867A. remain constant along the tubes length1868 B. be greatest in a single pass counter flow heat exchanger1869 C. remain constan

654、t throughout the heat exchanger1870 D. vary from section to section through out the heat exchanger1871 1865 The temperature differential occurring between the inlet temperature of the fluid to be cooled and the outlet temperature of the cooling medium in a shell-and-tube heat exchanger is greatest i

655、n which of the flow designs listed?18721865经过壳管式热交换器的热、冷两种流体，如果设计成对流流动，那么被冷却流体的进口温度与冷却介质的出口温度之间的温差最小，即冷却效果最好。题干中“greatest应改为smallest。1873A. Cross B. Parallel C. Counter D. Circular1874 1866 The general purpose of a heat exchanger is to _ 18751866热交换器的作用是用另一种流体来加热或冷却一种流体。1876 A. eliminate hot air fro

656、m the condenser1877 B. maintain steady pressure in a system1878 C. heat, or cool one fluid by means of another fluid1879 D. reduce the engine room temperature in tropical climates1880 1864 D 1865 C 1866 C1867Which of the following problems could ca the high pressure cutout switch to shut 1868 down t

657、he compressor in a refrigeration system?18691867冷凝器中冷却水量缺乏，将导致冷凝压力过高，从而使高压继电器产生动作使压缩机停转。1870A. A shortage of liquid refrigerant1871 B. Excessive frost on the evaporator1872 C. Excessive condenser cooling water1873 D. Insufficient condenser cooling water flow1874 1868 An increasing head pressure in a

658、 refrigeration system, without any corresponding change in the cooling water inlet temperature, would probably be caused by _ 18751868制冷系统中，冷却水进口温度没有变化，但冷凝压力增高，可能是由于系统中含有空气和其他不凝性气体。1876 A. restriction in refrigerant piping1877 B. air and non-condensable gases in the condenser1878 C. water in the ref

659、rigerant1879 D. flooding back of liquid refrigerant from the evaporator1880 1869 ff the refrigeration compressor was developing higher than normal discharge pressure, this could be a result of _ 18811869如果制冷压缩机的排出压力偏高，可能是由于系统中含有空气或其他不凝性气体。1882 A. air or non-condensable gases in the system1883 B. lea

660、king discharge valves1884 C. leaking suction valves1885 D. liquid refrigerant flooding back from the cooling coil1886 1867 D 1868 B 1869 A 1870 ff the head pressure of a reciprocating refrigeration compressor is excessive, _ 1870压缩机的排出压力过高，将使高压继电器产生动作使压缩机停转。A. the relief valve should open before the

661、 high pressure cutout B. the relief valve should open and allow the excess refrigerant to flow to the receiver C. the high pressure cutout switch should operate before the relief valve opens D. you should close in on the suction valve1871 Pitting in the suction areas of a centrifugal pump bronze imp

662、eller is usually caused by _ 1871离心泵叶轮吸口处起麻点，通常是由于气蚀引起的。A. cavitation B. electrolysis C. abrasion D. corrosionThe control mode in which the final control element is moved from one of two fixed positions to the other is known as _ 1872。最终的控制单元是从两个固定的位置之一移动到另一个位置，这种控制模式称为 “开关控制。(双位控制) A. dead band act

663、ion B. neutral zone action C. range D. on-off action1873 One cause of high head pressure occurring in a refrigeration system can be _ 1873、如果制冷压缩机的排出压力偏高，另一个可能原因是冷凝器冷却水缺乏。 A. insufficient cooling water flow to the condenser B. a low refrigerant charge in the system C. the liquid valve is open too mu

664、ch D. high evaporator superheat 1870 C 1871 A 1872 D 1873 A1874 The usual symptoms of cavitation in a centrifugal pump is _ 1874离心泵气蚀的常见征兆是噪声和振动。A. noise and vibration B. an increase in discharge pressure C. an increase in suction pressure D. lifting of the relief valve1875Which of the problems list

665、ed would cause the discharge temperature of an R- 12 1876 refrigeration compressor to increase?1875冷凝器堵塞或污垢将会引起刚2制冷压缩机排温升高。A. Thermal expansion valve frozen open. B. Suction gas heat exchanger bypassed. C. Condenser clogged or fouled. D. High pressure cutout switch inoperative.1876 Low compressor he

666、ad pressure in a refrigeration system can be caused by _ 1876如果制冷压缩机的排出压力偏低，可能原因是冷凝器冷却水过量 A. insufficient condenser cooling water B. excessive condenser cooling water C. air in the refrigeration system D. excessive refrigerant in the system 1874 A 1875 C 1876 B1877 A pressure drop through the refrig

667、erant liquid line may cause _ 1877液态制冷剂管路发生压力降，将会引起液态管路发生闪气。 A. solenoid valve to seize B. compressor to hunt C. formation of flash gas in the liquid line D. expansion valve to freeze open1878Heavy wear in a particular area of the inner circumference of a packing ring 1879 may be caused by _ 1878盘根环

668、内圆周特定区域严重磨损，通常是由于轴承严重磨损引起 A. a high suction head B. rotating rings C. badly worn bearings D. a loose stuffing box gland1879 Which of the listed pumps is NOT a positive displacement pump?1879离心泵不属于容积式泵：A. Centrifugal B. Reciprocating C. Gear D. Rotary1880 If the thermal bulb of an expansion valve is

669、incorrectly placed at the center of the coil in stead of the end, it will _ 1880热力膨胀阀的感温包应放置于蒸发盘管的出口端。如果放在蒸发盘管的中间位置，将会减少蒸发盘管的蒸发量。(因膨胀阀开度减小) A. increase the capacity of the coil B. increase the superheat at the bulb C. deliver more refrigerant to the coil D. decrease the capacity of the coil 1877 C 1

670、878 C 1879 A 1880 D1881 The major source of chemical contaminants in hydraulic fluid is _ 1881液压油的化学污染源主要是氧化产物。A. microscopic steel shavings B. abrasive waste C. anti-oxidant compounds D. oxidation by-products1882The amount of fluid friction or internal friction inherent in a mineral lubricating oil

671、 is 1883 reflected as a measure of its _ 1882润滑油中的内阻力大小是用帖度来表示的。A. specific gravity B. viscosity C. S.E. number D. hydrolytic stability1883 Thermostatic expansion valves can be adjusted for _ 1883热力膨胀阀仅用来调节过热度。 A. suction pressure only B. head pressure only C. superheat only D. suction pressure and

672、box temperature1884 A grease gun is generally used to lubricate a _ 1884牛油枪可用来润滑凝水泵(淡水泵)的球轴承。A. condensate pump ball bearing B. main shaft bearing C. main turbine bearing D. diesel engine wrist pin bearing1885 An internal bypass is provided on some hydraulic system suction strainers to help reduce the possibility of _ 1885，在液压系统吸口滤器中安装内部旁通管，以减少泵发生气蚀 A. aeration of the oil B. contamination of the oil C. pump cavitation D. spongy actuator movements 1881 D 1882 B 1883 C 1884 A 1885 C