Heat exchangers are vital parts of the devices and machineries used in heavy industries such as petroleum plants, power plants and oil refineries. These industries use machineries that not only need constant tune up but also in need of continuous cooling. Heat Exchangers do this specific job for them. Definition of Heat Exchangers Heat exchangers are devices that are installed to facilitate efficient heat transfers from one medium to another. These mediums are usually in the form of water and other liquids. During the process, a thin solid wall so as to not be in direct contact with each other may separate the liquids. There are also exchangers that let these liquids mix during the transfer process. There are many types of heat exchangers; one of them is the Shell and tube heat exchanger. The Shell and Tube Heat Exchangers A series of tubes make up a shell and tube heat exchanger. The tubes carry the liquids that will be processed by the exchanger. One set of tubes will carry the medium that will be in need of cooling. The other set of tubes will carry the liquid that will run through the other medium and provide the cooling for it. This process also goes the other way with the mediums either being cooled or heated. The set of tubes present in a shell and tube heat exchanger is called a tube bundle. The tube bundle is comprised of several different tubes in all shapes and sizes. A shell and tube heat exchanger is usually used for jobs that would require high pressures. The pressures that this particular exchanger typically deals with can be around 30 bars and be as high as 260 C. The strength of the tubes that make up this particular heat exchanger enables it to handle pressures this high. Some Considerations when Laying out Shell and Tube Heat Exchanger Pipes diameter The diameter of the tubes in the exchanger varies on how heavy and often you will be using the machinery. A smaller diameter for the tubes will make the heat exchanger compact and more efficient. But the setback is that, smaller tube diameters make the heat exchangers wore out more easily resulting in more dirt on the machine. Smaller tubes are also harder to clean than the larger ones. Thickness It is important for the tubes of the heat exchanger to be thick. A thick tube ensures that the heat exchanger can have enough room for corrosion and resistance during the process. A thick tube will also ensure that the exchanger will provide enough axial, hoop and buckling strength during the exchange process. Length A longer tube and small diameter for exchangers are usually cheaper to set-up. Typical shell and tube heat exchangers are usually made to be as long and small as possible whilst not compromising the whole quality of the exchanger. Though this set-up provides plenty of limitations for the machine, many machines still employ this set-up because of its economic advantages. Source: hicow.com/heat-exchanger
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