The stainless steel metal plates of the plate heat exchanger are assembled and installed in an inverted mode. This can form a mesh contact, so that the fluid in the channel becomes a mesh fluid. So that the fluid flows from one end to the other end as a unidirectional circulation circuit, or forms a diagonal flow in the opposite direction to achieve the purpose of heat transfer.Plate heat exchanger is an ideal equipment for liquid-liquid, liquid-vapor heat exchange. It has the characteristics of high heat exchange efficiency, small heat loss, compact and lightweight structure, small footprint, wide application and long service life. The main reasons for corrosion leaks in stainless steel plate heat exchangers are: (1) the change of the chloride ion concentration in the medium;(2) Using the flow rate in the medium, the intuitive point is the concentration of oxygen.(3) Changes in temperature will also have an effect because the increase in temperature will accelerate the diffusion rate of oxygen and chloride ions.