Pneumatic control valve is one of the widely used instr […]
Pneumatic control valve is one of the widely used instruments in petrochemical enterprises. Its accurate and normal operation is of great significance to ensure the normal operation and safe production of the process equipment. Therefore, it is necessary to strengthen the maintenance of the pneumatic regulating valve.
Key inspection site during maintenance
Check the inner wall of the room: in the case of high pressure difference and corrosive medium, the diaphragm of the inner wall of the valve and the diaphragm valve are often subjected to the impact and corrosion of the medium, and the pressure and corrosion resistance must be checked.
Check valve seat: due to medium infiltration during operation, electric Y-type trap, the inner surface of the thread for fixing the seat is susceptible to corrosion and the seat is slack;
Check the valve core: the valve core is one of the movable parts of the regulating valve. It is seriously damaged by the medium. During the inspection, it is necessary to carefully check whether the various parts of the valve core are corroded and worn, especially in the case of high pressure difference. The cavitation caused by cavitation is more serious. Severely damaged spools should be replaced;
Check the sealing packing: check whether the packing asbestos rope is dry. If using PTFE packing, pay attention to check whether it is aging and whether its mating surface is damaged;
Check if the rubber film in the actuator is aging and cracked.