U-shaped tube heat exchanger is a kind of tube and shell heat exchanger. It consists of tube sheet, shell, tube bundle and other components. Under the same diameter, the heat exchange area of U-tube heat exchanger is the largest. It has a simple structure, compact structure, high sealing performance, convenient maintenance and cleaning, and minimal metal consumption under high temperature and pressure. The U-shaped tube heat exchanger has only one tube sheet, which has good thermal compensation performance and strong pressure bearing capacity, and is suitable for operation under high temperature and high pressure conditions. Each tube is bent into a U-shape and fixed on the same side tube plate. Each tube can be freely expanded and contracted to eliminate thermal stress. What are the performance characteristics of U-tube heat exchangers
1.U-tube heat exchanger advantages
(1) The characteristic of the heat exchanger is that the tube bundle can be freely expanded and contracted, and no thermal stress will be generated due to the temperature difference between the tube and shell, and the thermal compensation performance is good.
(2) The tube side is a double tube side, with a longer process, higher flow rate, better heat transfer performance, and higher pressure capacity
(3) The tube bundle can be pulled out of the casing, which is convenient for maintenance and cleaning, and has a simple structure and low cost.
2. Disadvantages of U-shaped tube heat exchanger
Cleaning inside the tube is inconvenient, and the tube in the middle of the tube bundle is difficult to replace. The bending radius of the innermost tube cannot be too small, and the tube distribution in the center of the tube sheet is not compact, so the number of tubes cannot be too large. There is a gap in the central part of the tube bundle, which makes the shell-side fluid easy to short circuit and affects the shell-side heat transfer.
In order to compensate for the thinning of the pipe wall after the bend, a thicker pipe is needed for the straight pipe part. This affects its use case. It is only used in the case where the temperature difference between the shell and the wall is large, or the medium at the shell side is prone to fouling, while the medium at the pipe side is clean and difficult to foul, high temperature, high pressure, and corrosive conditions.