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1、OO.Oi压力表简介 Introduction to Pressure Gauge式压力表 Mechanical Pressure Gauge:在工业过程控制与测量已程中.由于机械式压力表的弹性敏感元件具有较高的机械强度.且生产方便、成本低廉.使其在各工 业领域得到极为广泛的应用。机械式压力表通常采用弹簧管（波登管）、膜片、膜盒或波纹管等弹性敏感元件。弹性元件在介质压力作用下产生的弹性变形. 通过齿轮传动机构（初芯）放大，从而由指针在度盘上指示出相应的压力值。度盘的刻度范围通常制成270。During industrial continuing and measuring process. T
2、he elastic sensitive elenient of lhe mechanical pressure gauge is used widely in all kinds of industrial fields due to its high mechanical strength, tow price and convenient production methods.The mechanical pressure gauge is often made of Bourdon tube diaphragm capsule or bellow tube These elements
3、 should be elastic deformed by die medium pressure The signals would be enlarged by the movements, and the pointer should then be able to point to the number on the diaL to indicate the pressure The effective measuring range on the dial is usually within 270 degree of a circle压力表的分类The Types of Pres
4、sure Gauge:压力表按测量精度accuracy.可分为精密压力表、一般压力表。精密玉力表的测星培确度等级分别为0.1、0.16. 0.25. 0.4级； 一般压力表的测量精确度通常为1.0、1.6、2.5级。仪表的精确度等级由除测量范围90%以上部分外的其余部分的基本误差限决定， 基本误差限依据仪表童程及精确度等级.按引用误差计竈 如06MPa、1.6级仪表.其基本误差限为土 （6x 1.6% ）MPa= 0.096MPa,压力表按指示压力基准的不同.分为压力表、绝对压力表、差压表。一般压力表以大旬玉力为测量基准；绝对压力表以绝対丘 力零位为测星基准；差压表测量两个被测压力之差。压力表
5、按测量范围.分为頁空表、压力真空表、微压表、低压表、中压表及高压表。真空表用于测量小于大气压力的压力值（负 压）；压力真空表用于测童小于及大于大气压力的压力值（正负压）；微压表限不大于60000Pa：低压董的测量上限不大于 6MPa：中压表的测量上限不大于60MPa;高压表的测量上限可以达到lOOMPa以上。耐震压力表的表壳被制成全密封结构.且在表壳内填充阻尼油。由于其阻尼作用.仪表可使用在工作环境振动或介质压力（负 荷）脉动的场所。电接点压力表带有电接点控制幵关.可以实现发讯报警或控制功能。远传压力表带有远传机构，可以提供工业过程中所需要的电信号（比如电阻信号或标准直流电流信号）。隔膜压力表
6、所使用的隔离器（化学密封）.能通过隔离膜片将被测介质与仪表隔离.以测量强氏蚀、高温、易结晶介质的压力The Pressure gauge should be divided into two categories according to its accuracy: Precise Pressure Gauge and Generally Pressure Gauge The accuracy of precise pressure gauge: 0.L 0.16. 0.25, 0.4 grade The accuracy of generally pressure gauge: l0. 1.
7、6. 2.5 grade The grade of accuracy is detennined by tlie intrinsic error outside of 90% of the measure range. The intrinsic error standard is determined by the accuracy grade and its measuring range For example the intrinsic error staiulard for a gauge with 0-6MPa and 1.6 grade, its imrinsic error s
8、tandard should be （6x 1.6%） =0.096VIPa.The pressure gauge shoukl be divided into d it fere nt types according to the measuring benchmark, such as generally pressure gauge absolute pressure gauge, differentuil pressure gauge generally pressure gauge use atnx）spheric pressure benchmark, absolute press
9、ure gauge use absolute pressure zero as the benchmark, and differential pressure gauge measures the difference value between two gaugesThe pressure gauge should be divided into diiYerent types by its measuring range: vacuum pressure gauge, compound pressure gauge micro pressure gauge low pressure ga
10、uge, middle pressure gauge and high pressure gauge The vacuum pressure gauge is used to mcasum the negative pressure that is lower than the standard atmospheric pressure Compound pressure gauge is used to measure the pressure that is either higher or lower than the sUindard atmospheric pressure Micr
11、o pressure gauge could not measure more than 60000Pa. low pressure gauge could not measure more than 6MPx middle pressure gauge coukl not measure higher tlian 60MPa and high pressure gauge couki measure higher than lOOMPa.The shake-resist pressure gauge with a airtight type case, with liquid filled
12、case for applications with high dynamic pressure loads or vibrations.The electric contact pressure gauge with a electrical contact switch .which should be used for alarming or controlling functions Transmissible pressure gauge with a remote transmission structure and should be used to deliver the el
13、ectrical signals （such as resistance signal or direct electrical current signal） during industrial processDiaphragm seal pressure gauge with a diaphragm seal which couki separale the medium witli the gauge effectively by the diaphragm, to measuring the pressure of medium which is strong corrosive hi
14、gh temperature, aggressive and highly viscous containing suspended matter or cryslaL压力表的弹性元件 The sensitive elements of the pressure gauge:压力表的弹性敏感元件随着压力变化而产生弹性变形.以间接测童介贯压力。弹性元件一般由铜合金、不锈钢或将殊材料制匪 弹簧管（波登管）分为C形管、盘簧管、螺旋管等多种型式O弹簧管在内腔压力作用下.利用所具有的弹性特性.可以方便地 将压力转变为弹簧管自由端的弹性位移。弹簧管的量程一般为0.1 MPa -250MPao膜片的截面呈波
15、纹状。膜片本身位于两个法兰之间.或焊接在法兰上.膜片一侧承受测量介质的压力。膜片与波登管相比传递 力更尢防振性较好.可达到较高的过压保护及耐馄蚀性。膜片压力表的量程为lkPa2.5MPao膜盒由两块对扣在一起的膜片组成.测量介质的压力作用在膜盒腔内侧。几个膜盒敏感元件叠在一起后（波纹管）会产生较大 的传递力来测量极小的压力。膜盒压力表的星程为250Pa100kPaoThe clastic sensitive element of the pressure gauge should be defonned plastically, to measure the medium pressure T
16、he element e usually made of copper alloy, stainless steel or other special materialThe Bourdon tube should be divided into types such as C shaped tube Spring tube or spiral shaped tube The Bourdon tube should turn lhe pressure into the distance moved by the elastic character. The measuring range for the Bourdon tube is usually 0.1 一 250 MPa.The cross section of the diaphragm is usually waxy The diaphr
