能请高手帮我翻译一下吗?不胜感激!

能请高手帮我翻译一下吗?不胜感激!
U-tube. As the name implies, the tubes of a U-tube heat exchanger
(Figure 3) are bent in the shape of a U. There is only one tubesheet in a U-tube heat exchanger. However, the lower cost for the single tubesheet is offset by the additional costs incurred for the bending of the tubes and the somewhat larger shell diameter (due to the minimum U-bend radius), making the cost of a U-tube heat exchanger comparable to that of a fixed-
tubesheet exchanger.
The advantage of a U-tube heat exchanger is that because one end is free, the bundle can expand or contract in response to stress differentials. In addition, the outsides of the tubes can be cleaned, as the tube bundle can be removed.
The disadvantage of the U-tube construction is that the insides of the tubes cannot be cleaned effectively, since the U-bends would require flex-ible-end drill shafts for cleaning. Thus, U-tube heat exchangers should not be used for services with a dirty fluid inside tubes.
Floating head. The floating-head heat exchanger is the most versatile type of STHE, and also the costliest. In this design, one tubesheet is fixed relative to the shell, and the other is free to “float” within the shell. This permits free expansion of the tube bundle, as well as cleaning of both the insides and outsides of the tubes. Thus, floating-head SHTEs can be used for services where both the shellside and the tubeside fluids are dirty — making this the standard construction type used in dirty services, such as in petroleum refineries.
There are various types of floating-head construction. The two most common are the pull-through with backing device (TEMAS) and pull-through (TEMAT) designs.
The TEMAS design (Figure 4) is the most common configuration in the chemical process industries (CPI). The floating-head cover is secured against the floating tubesheet by bolting it to an ingenious split backing ring. This floating-head closure is located beyond the end of the shell and contained by a shell cover of a larger diameter. To dismantle the heat exchanger, the shell cover is removed first, then the split backing ring, and then the floating-head cover, after which the tube bundle can be removed from the stationary end.
In the TEMA T construction (Figure 5), the entire tube bundle, including the floating-head assembly, can be removed from the stationary end, since the shell diameter is larger than the floating-head flange. The floating-head cover is bolted directly to the floating tubesheet so that a split backing ring is not required. The advantage of this construction is that the tube bundle may be removed from the shell without removing either the shell or the floating-head cover, thus reducing maintenance time. This design is particularly suited to kettle reboilers having a dirty heating medium where U-tubes cannot be employed. Due to the enlarged shell, this construction has the highest cost of all exchanger types.

U-内胎.按照那个名,U-内胎的内胎There热起来使交换器(图3)只是一个的tubesheet,并且做了U.的型的倾向性是U-内胎热交换器.但是低给一个的tubesheet的成本被用为把相当的贝壳直径(为改变最小限度的U-,半径)比内胎和几分折弯被邀请的补充费用抵消.以及用U-内胎热交换器的成本相当于fixed-tubesheet交换器的那个.
是否因为一端免费所以U-内胎热交换器的长处能扩大束是能根据紧张状态差别缩小.那||饥饿,并且能被除掉内胎束,内胎的外侧变得能干净.
是为了U-内胎建设的不利内胎的界内有效,并且不变得能从U-转角为打扫需要弯曲-ible-结束训练车轴的时候起干净.这样U-内胎热交换器不可以被为对卑鄙流体的工作在内胎里使用.
正有剩余的最初.正松脱的头热交换器在STHE,更加最高高具有的东西最是可以通融的型.用这种式样,一个的tubesheet跟贝壳比较,被固定以及以外能在贝壳的范围中"松脱".这个饶恕内胎束(与内部有关人员和内胎的外侧的打扫同样)的自由的扩大.能被为shellside和tubeside流体在方面吝啬的服务雇用这样正松脱的头SHTEs — 在在这个方面吝啬的服务,比方说做被在石油精制工厂使用的标准建设活字.
有正松脱的各种各样头建设.和作为提拔的-补助装置(TEMAS)拉两的大部分期间的普通股份,并且彻底(TEMAT)||用式样||一直.
TEMAS式样(图4)由于在化学上生产流程产业(CPI)最是一般的构成.正松脱的头覆盖物把伏特留在破了的巧妙补助环,并且决定做那个||依靠,被针对正浮在上的tubesheet固定.这个正松脱的头封闭超越炮弹的端而位于,被用相当的直径的贝壳覆盖物更里面含有.填补正浮在上的头以及,为分解热交换器贝壳覆盖物被最初去掉以及破了补助环,随后能被然后除掉静止了的结束内胎束.
能被比贝壳直径正浮在上由于TEMA T制作(图5)的头法兰从大时候起除掉静止了的结束所有内胎束(包括正松脱的头集会在内).好象不需要破了的补助环,并且正松脱的头覆盖物把伏特留在正浮在上直接的tubesheet,并且被做.是为了不内胎束去掉贝壳或者正松脱的头覆盖物而也许这个建设的长处被贝壳除掉.这样把管理时间减少.这种式样正适应正特别具有不能被用于上U-内胎的卑鄙暖气媒体的水壶再沸器.为扩大了的贝壳,这个建设正有所有交换器型的最高的成本