The plate heat exchanger consists of a set of rectangular thin corrugation metal heat transfer plates that are clamped and assembled to the frame by a frame set. The edge lining of two adjacent plate is tightly sealed with a rubber gasket. The material of the gasket is usually composed of various rubber or compressed asbestos, and is selected according to different treatment media. The four corners of the plate are provided with round holes, and the gaskets are stacked to form a passage for the fluid. Fluid media of different temperatures flow from both sides of the plate to exchange heat through the gasket. Plate heat exchangers are widely used in metallurgy, petroleum, chemical, food, pharmaceutical, shipbuilding, textile, paper and other industries. They are excellent equipment for heating, cooling, heat recovery and rapid sterilization.