A Description of Shell and Tube Heat Exchangers
Shell and tube heat exchangers are needed for high-pressure applications; they are durable products, which can withstand the demands of many working environments. Their design plays a large part in ashell and tube exchanger's ability to endure exceedingly-challenging situations. Shell and tube heat exchangers are made from a series of tubes, which can be made of durable material such as fluoropolymers. Fluoropolymers are highly-durable plastics such as PTFE, FEP, and PFA. Fluoropolymers, like heat exchangers, have a place in a variety of industries such as the automotive, medical, and aeronautical.
In a exchanger's shell, one set of tubes contains fluid, which is either heated or cooled. Another set of tubes also contains liquid, which facilitates the heating or cooling of the primary set of tubes. A tube set is referred to as the tube bundle and can take on a variety of shapes depending on what is most conducive for the intended job. Engineers of shell and tube heat exchangers need to consider several components of construction:
A smaller tube diameter enables the shell and tube exchanger to be economical and compact, yet a tiny diameter can facilitate malfunction and difficulty of cleaning. Larger tubing can be instituted to eradicate potential flow and cleaning problems. Engineers must factor cost, space, and the propensity of liquids to foul when constructing a heat exchanger. Tube thickness is important to make sure there is room for corrosion; vibration existing in the product has resistance; and, the shell and tube exchanger can withstand pressure coming from both in and outside of its internal tubes.
Folding or wrinkling the inner tubes increases the flow of the liquid, which facilitates the transfer of heat, producing better performance from the exchanger. Designers also consider the layout of the inner tubes. Tubes can be fashioned in a triangular, square, rotated square, or rotated triangular fashion. Particular, internal designs are conducive to specific jobs and the elimination of potential problems such as fouling of the liquid.
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