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1、书名：热加工专业英语 第2版 ISBN： 978-7-111-49332-7 作者：王晓江 出版社：机械工业出版社 本书配有电子课件热加工专业英语教案陕西工业职业技术学院材料成形教研室Chapter Two Unit 10 The Cupolaw教学目标及要求1.掌握课文中有关冲天炉结构及熔炼的专业词汇和专业术语 ；2.结合冲天炉的相关专业知识阅读课文，提高翻译能力。 w重点1.冲天炉结构及熔炼的专业词汇和专业术语；2. 课文翻译重点： 冲天炉的结构；冲天炉的熔炼原理；冲天炉熔炼的特点。u难句分析及翻译的基本技巧Part（） 科技英语疑难结构及其翻译四、Than 结构w教学思路设计时间分配（共
2、100min）：1、讲解课文中的专业词汇和术语；2、讲解课后生词、大声朗读；3、翻译课文，注意穿插相关专业知识；4、分析难点句型，讲解相关语法和翻译技巧；5、学生答疑。Contents wNew Words wPhrases and Expressions wText Analysis wQuestions wGlossary of Terms wLanguage Points of these, about 80 are metals.w人类已知的化学元素有100种以上，其中有80种是金属。 3. “less than + 数字”w这一结构一般译成“ 以下”、“不到 ”。 wThe carb
3、on content in mild steel is less than 0.3 percent. w中碳钢的含碳量在0.3%以下。 4. “less than”w在这一结构中, less 与than 分开使用，用法与less than 不同，它相当于“not so as”结构，译成“比小”、“不 及”、“不如”等。 wThe electrons meet less resistance when the conductor is cold than when it is hot.w电子在导体冷却时遇到的阻力比导体热时的小。 5. “other than”w这一结构一般译成“除之外”、“不仅
4、而且还”。wThere are practical sources of heat energy other than the combustion of fossil fuels.w除了燃烧矿物燃料外，还有一些实用的热源。6. “rather than”w这一结构一般译成“而不是”。 wIt is for the travelers rather than the enthusiasts that the railways must be run.w经营铁路是为了旅客而不是为了铁路爱好者。 7. “would rather than”w在这一结构中，可把“would rather A tha
5、n B”顺译成“宁可 A而不愿B”，或逆译成“与其B倒不如A”。 wWe would rather go on with the experiment than give it up.w我们宁愿把这项实验进行下去，而不愿放弃不做。8. “nothing more than” w这一结构一般译成“只不过”或“仅仅是”。 wThe thermostat is nothing more than an electric switch that opens and closes itself at the proper temperature. w恒温器只不过是到达适当温度就自动开、关的电闸。 9.
6、“no more than” w这一结构与上一结构相似，一般译成“只不过”或“仅仅是”。 wThis first orbit nearest to the nucleus contains no more than 2 electrons. w最靠近原子核的轨道仅仅含有两个电子。 10. “no sooner than” w这一结构一般译成“一就”、“刚就”等。 wThe push button had no sooner been depressed than the motor began to run. w按钮刚一压下，马达就开动了。 Reading MaterialswMelting
7、of Nonferrous Metals Some nonferrous metal melting is done in almost all types of furnaces. More and more is done in induction furnaces for reasons of convenience, ease of operation, and fewer environmental problems, but oil- and gas-fired crucible furnaces have advantages. Although the fuel cost is
8、 about the same for both types of furnaces, an electric furnace may cost 10 to 15 times as much initially as an oil- or gas-fired one. Modern electric furnaces have complicated controls and are costly to service, whereas all a fossil-fuel furnace needs is relining from time to time. 感应炉坩埚炉化石燃料炉On th
9、e other hand, oil- and gas-fired furnaces create heat, fumes, and noise problems. A stack is needed, and a baghouse may be required depending upon local environmental regulations. It is difficult to find people to work around hot fumes, particularly in hot weather. Two types of crucible furnaces are
10、 stationary and tilting furnaces. The stationary type of crucible furnace requires that the crucible be lifted in and out for pouring. A cross section of this type of furnace is shown in Fig.3-10-2. When a stationary furnace is sunk into the floor or deck of a foundry, it is known as a pit-type furn
11、ace.地坑炉Fig.2-10-2 Cross section of a stationary type A tilting type of crucible furnace, Fig.2-10-3, requires a crucible with a suitable lip for pouring metal when the furnace is tilted.Most nonferrous metals and alloys oxidize, absorb gases and other substances, and form dross readily when heated.
12、Various practices are followed for each kind of metal to preserve purity and obtain good castings. Space does not permit descriptions of all, and full information may be found in treatises on the subject. The melting of aluminum will be treated in some detail here to point out the nature of the prob
13、lems and principles.可倾斜式坩埚炉Fig.2-10-3 Tilting type crucible furnacewInduction FurnacesBecause of their very rapid melting rates and relative ease of controlling pollution, the use of electric induction furnaces has increased extensively. Two types are used. The high-frequency type, or coreless induc
14、tion furnace, shown in Fig.2 -10-4, consists of a crucible surrounded by a water -cooled coil of copper tubing. A high-frequency electrical current passes through the coil, establishing an alternating magnetic field, which, in turn, induces secondary currents in the metal in the crucible. These seco
15、ndary currents heat the metal very rapidly.感应电炉水冷线圈磁场These furnaces are used for virtually all common alloys, the maximum temperature being limited only by the refractory and efficiency of insulating against heat loss. They provide good control of temperature and composition and are available in cap
16、acities through 65 tons. Because there is no contamination from the heat source, they produce very pure metal.w Low-frequency, or channel-type, induction furnaces are being used increasingly. As indicated in Fig.2-10-5, these have an ordinary alternating- current primary coil, but the secondary coil is formed by a loop, or channel, of the molten metal. Because the secondary coil
