Shell-and-tube heat exchanger, as a traditional heat exchanger, has been widely used in many industries, especially in chemical, petroleum, energy and other industries. In recent years, shell-and-tube heat exchangers have been challenged to some extent by new types of heat exchangers, but they have the advantages of simple structure, strong strength, large operating flexibility and wide application of materials, in the chemical industry, petroleum, energy and other industries are still in the dominant position.