Cover plate heat exchangers are generally used for dirty fluids with low design pressures, such as for machinery oil cooling and heavy hydrocarbons. Plate type heat exchanger is a kind of high-efficient heat-exchanging equipment made by stainless steel sheet metal. Cold and hot fluids flow in (and out) through vents at four corners of sheet to produce heat-exchanging effect, besides, in order to prevent mixing and leakage of cold and hot fluids, rubber spacers are used to seal between sheet metals. Numerous ripple plates and spacers are assembled in the frame, which is made up of compression plates and leaders, and then they are compacted with compression studs. The heat-exchanging area is confirmed according to heating-exchanging volume. This configuration is ideal with dirty and low-pressure applications.