Plate heat exchanger is a kind of high-efficiency heat exchanger made of a series of metal plates with a certain corrugated shape. With its unique working principle and unique composition structure, it stands out from many heat exchangers. The correct maintenance method of the plate heat exchanger is as follows:
(1) Close the medium inlet valve before disassembly (close the high-pressure side valve first, and then close the outlet valve). The heat exchanger is slowly cooled down to 40 ° C before being discharged, and the connected pipes are removed before the whole can be lifted off.
(2) After the system gas, pressure, temperature and other parameters meet the maintenance requirements, they can enter the site construction.Remove the nozzle and loosen the fixing bolts in the diagonal direction.During the disassembly process, the width of the movable platen should not exceed 10mm, and the vertical deviation should not exceed 25mm. The movable platen should always be moved in a parallel state.Remove the plate and tilt the plate 15 ° -20 ° to one side. You can remove it by lifting it slightly. Do not remove it forcibly to prevent the upper positioning groove from being deformed or damaged.
(3) Check the heat exchanger plates. The plate should be free of cracks, scratches, deformation and other defects.The uneven thickness deviation shall not exceed 5%. The periphery of the plate should be smooth and flat, and the shape of the sealing groove should meet the requirements of the drawing. The allowable deviation of the depth is 0.1mm. The sealing surface must not have defects that affect the sealing performance such as bumps, wrinkles, twists, and scratches. The allowable deviation of the plate corrugation depth is ± 0.2mm, and the unevenness must not be greater than 1%. For perforated plates, hydrogen arc welding can be used to repair and smooth them.