Pneumatic control valves are widely used in petrochemical, power plants, iron and steel metallurgy, food processing, and water treatment industries, especially in large enterprises that require automatic control. The electric valve also creates conditions for the remote control of the valve, thus realizing the automation and intelligence of the production system. However, when the pneumatic control valve is in use, the valve may not be closed tightly, which will not only cause trouble to users and operators but also seriously affect the service life of the pneumatic control valve. So how to solve the problem that the pneumatic control valve is not closed tightly?
1. There are impurities on the sealing surface of the valve
If the valve closes suddenly, there may be impurities on its sealing surface. Do not forcibly close the valve at this time. Try turning it on a bit, then turning it off. During the test, the quality of the medium should be kept clean.

2. The thread on the valve stem is rusted
For normally open valves, if closed accidentally, the threads on the stem may rust and not close properly. In this case, the valve can be opened and closed multiple times without grinding or repairing, and the valve can be closed by hitting the bottom of the valve body with a small hammer.

3. Damaged valve sealing surface
If the switch does not fully close after several attempts, i.e. the sealing surface is damaged, the repair status should be reported. If the sealing surface is damaged due to corrosion of the medium or scratches by particles, it should also be repaired.

4. Incorrect connection between the valve stem and the valve disc
Lubricate the stem and nut of the pneumatic control valve to ensure flexible opening and closing of the valve.