If the plate heat exchanger leaks, replace the leaking plate instead of further tightening the bolts. When the bolts are tightened, the deviation of the measured plate length of adjacent bolts shall be carried out in accordance with relevant standards. When the plates are stacked together, the width of the plate bundle is less than 1000 mm, and the deviation after tightening is no more than 1 mm. When the width of the plate bundle is greater than 1000 mm, the error after tightening is not greater than 2 mm. In general, the allowable pressure of plate heat exchange equipment is about 2.5MPa and the allowable temperature is 160°C. But in the refrigeration system, the working pressure can be around 1.6MPa.
1. Prevent the scaling of equipment plates.
(1) The internal surface of the circulating water side plate is seriously polluted, the bottom of the pollution layer is hard, the surface layer is thick, and the gray sediment is loose.
(2) There are a lot of impacting foreign matter on the circulating water side, mainly concentrated in the water system flocs, shunts and fillers, causing partial blockage of the fluid between the plates. The filter cooling water should be equipped with softened water. It is recommended that the evaporator heat pump use less tap water as the medium. Consider using distilled water, neutral water and other pure water. If the circulating water has high hardness, it should be softened in advance.
2. The inside of the plate is cracked. If the heat exchanger is used as an evaporator, the temperature of the evaporator below 0°C will cause an ice layer between the plates and crack the equipment. When the equipment is used as an evaporator, it should be protected by antifreeze electromechanical. The second is to select a suitable flow, configure a flow switch, and install a low-pressure control switch for the suction line to prevent excessive cooling of the refrigerant.