A kind of shell-and-tube heat exchanger, which belongs to petrochemical equipment, consists of main parts such as tube box, shell and tube bundle. It is named after its heat exchange tube is U-shaped. The U-shaped tube heat exchanger has only one tube plate, and both ends of the tube are fixed on the same tube plate. The characteristic of this type of heat exchanger is that the tube bundle can be expanded and contracted freely, no thermal stress will be generated due to the temperature difference between the tube and the shell, and the heat compensation performance is good; the tube pass is a double pass, the process is longer, the flow rate is higher, and the heat transfer performance is better. ; Strong pressure-bearing capacity; the tube bundle can be drawn out from the shell, which is convenient for maintenance and cleaning, and has a simple structure and low cost.