What should be done if a position holding valve cannot hold its position?
Thread Content
What should be done if a position holding valve cannot hold its position? What should be done if the position cannot be maintained after the instrument air is cut off?
People who specialize in control valves say that when the air supply for these valves is cut off, the valve can maintain its position using the gas available in its own cylinder. But this position cannot be maintained all the time. Maybe an hour, two hours – during that time you need to handle the situation urgently; if that’s not possible, you have to stop the vehicle.
A position-retaining valve is essentially a normally closed pneumatic valve that opens when there is air pressure; it functions as a section of pipe through which compressed air flows. When the air pressure is lost, the valve closes, sealing the compressed air inside the cylinder and thus maintaining its position. However, as a valve, it can still leak, and it is not possible to keep it completely sealed forever. Therefore, it is necessary to address any issues as soon as they arise; one cannot rely entirely on the position-retaining valve. Additionally, the valve might be damaged, as it is a mechanical device that can suffer damage and has a limited service life. Any problems should be checked and resolved promptly.