The plate heat exchanger has a simple structure and is mainly composed of three main parts: a sealing gasket, a pressing device, a heat transfer plate and other components such as nozzle, shaft etc.(1) Heat exchangers plates. The most critical component of the plate heat exchanger is the heat transfer plate, which has a wide variety of heat transfer plates. The most common heat transfer plates are: spiral plates, herringbone plates and horizontal flat corrugated plates.(2) The sealing gasket can effectively prevent the internal leakage between the two different fluids and the out leakage. In the operation of the equipment, the sealing gasket needs to withstand different temperatures and different pressures and is eroded by the internal fluid, which is an important component of the alfa laval plate heat exchanger slection.(3)Different numbers of fixed and movable compression bolts and compression plates form another key component of the plate heat exchanger- the compression device. The pressing device is mainly used for pressing the sealing gasket to realize the sealing inside the heat exchanger, so that the fluid does not leak, and the pressing device mainly generates the pressing force by pressing the bolt.