The plate heat exchanger is a heat exchanger plate made of thin metal plates pressed into a certain herringbone corrugated shape, which is formed by stacking and fastening with frame plates and bolts. The working fluid flows through the narrow and tortuous channel formed between the two plates. The hot and cold fluids exchange heat through the flow channels in turn. The structure and heat exchange principle of the plate heat exchanger determine that it has the characteristics of compact structure, small footprint, high heat transfer efficiency, large operation flexibility, wide application range, small heat loss, easy installation and cleaning.In order to reduce the inspection, maintenance and cleaning of stainless steel plate heat exchangers, a coarse filter is usually provided on the inlet and outlet of the cold and hot medium to prevent 3-5mm particulate debris from blocking the plate channel.When the pressure difference between the front and back of the filter is large, the filter can be disassembled and cleaned. Cleaning the filter too frequently can also cause the stainless steel plate heat exchanger to fail due to blockage of the plate channels.