Shell and Tube Heat Exchanger: The Tube Specifics

Posted on September 22, 2011 

As one of the most basic and commonly used heat exchanger designs in the business, understanding the construction and key components of shell and tube heat exchangers is advisable. Available in a wide range of sizes, its innate mechanical ruggedness ensures that it will work well and last a long time for its various heating and cooling customer needs. Because the metal material of both the shell tube and the internal bundle of tubes should be conductive, corrosion resistant and resilient, stainless steel or copper alloys are often the choices when constructing the shell and tube heat exchanger.
Tubes are arguably the most important aspect of this heat exchanger model, especially considering that the basic structure is a series of tubes within a giant tube, like the basic tube heat exchanger it is similar to. They provide the heat transfer surface, be it cooling down or heating up, between one fluid moving inside the internal tube system and the other fluid flowing across the outside of the tube system but still within the structure of the shell. Sometimes seamless and sometimes welded, the tubes aesthetics vary on the fluids that will be within and around them. For example, a tube will have an enhanced surface if the fluid it will be processing has a low heat transfer.
Another important aspect of tubes is the tube sheet, which keeps the tubes in place within the shell tube frame. The bundles of tubes may be sitting in grooves within the tube sheet or actually welded onto the sheets, as well as keeping the gaskets, spacer rods and the bolt circle all stabilized too. How many sheets and tubes and other heat exchanger parts are present depend on the purpose of the model; for example, a double tube sheet is necessary when the two fluids may absolutely not come in contact, and all possibilities of leaks must be protected against. The dimensions of the tubes also always depends on its use.