A shell and tube heat exchanger consists of components such as a shell, heat transfer tube bundle, tube plate, baffle plate (baffle), and tube box. The shell is mostly cylindrical, with a bundle of pipes installed inside, and the two ends of the bundle are fixed on the tube plate. There are two types of fluids for heat exchange: cold and hot. One flows inside the tube and is called the tube side fluid; Another type of flow outside the tube is called shell side fluid. To improve the heat transfer coefficient of the fluid outside the pipe, several baffles are usually installed inside the shell. Baffles can increase the fluid velocity on the shell side, forcing the fluid to pass through the tube bundle multiple times according to the specified path, and enhancing the degree of fluid turbulence. The heat exchange tubes can be arranged in equilateral triangles or squares on the tube plate. The equilateral triangle arrangement is relatively compact, with a high degree of turbulence in the fluid outside the pipe and a large heat transfer coefficient; A square arrangement makes cleaning outside the pipe convenient and suitable for fluids that are prone to scaling.