Tube and tube heat exchanger is a widely used heat exchanger in chemical and alcohol production. It is mainly composed of shell, tube plate, heat exchange tube, head, baffle, etc. The required materials can be made of ordinary carbon steel, copper, or stainless steel. During heat exchange, a fluid enters from the connecting pipe of the head, flows through the pipe, and exits from the outlet pipe at the other end of the head, which is called the pipe side; Another type of fluid enters through the connecting pipe of the shell and flows out from another connecting pipe on the shell, which is called the shell side.