Plate heat exchanger is a new heat exchange product developed recently. It is widely used in light industry, medicine, petroleum, chemical, machinery, metallurgy, mining, power and shipbuilding industries. Its single-plate heat exchange plate area has reached 2㎡. The pressure used is 1.6 to 2.4 MPa. In addition to the conditions of use, The length of service life of the plate heat exchanger is determined by the two main factors: First, the quality of the metal plate is the pressure resistance and corrosion resistance of the metal plate, and the second is the rubber seal. The quality of the mat (clamped in the side grooves between the two sheet metal sheets) is the physical properties of the gasket. At present, the insufficiency of the gasket is that the compression deformation of the rubber gasket is too large under high temperature conditions, causing the heat exchanger to leak and the equipment cannot operate normally.