safety valve|Common faults of safety valve

1. The disc does not return to its seat after discharge: this is mainly caused by the spring bending the valve stem, the improper installation position of the disc or the jamming. Should be reassembled.
2. Leakage: Under the normal working pressure of the equipment, the leakage between the valve disc and the sealing surface of the valve seat exceeds the allowable degree. The reason is: there is dirt between the valve disc and the sealing surface of the valve seat. You can use the lift wrench to open the valve several times to flush away the dirt; the sealing surface is damaged. According to the degree of damage, the method of grinding or grinding after turning should be used to repair; the valve stem is bent, inclined or the lever and the fulcrum are deviated, so that the valve core and the valve disc are misaligned. Should be reassembled or replaced; the elasticity of the spring is reduced or loses its elasticity. Measures such as replacing the spring and re-adjusting the opening pressure should be taken.
3. Does not turn on when the specified pressure is reached: The reason for this situation is the inaccurate constant pressure. The compression amount of the spring or the position of the heavy hammer should be readjusted; the disc and the valve seat are stuck. The safety valve should be manually deflated or drained regularly; the lever of the lever-type safety valve is stuck or the hammer is moved. The position of the heavy hammer should be readjusted and the lever can move freely.
4. The pressure continues to rise after exhaust: This is mainly because the selected safety valve displacement is less than the safety discharge volume of the equipment, and a suitable safety valve should be selected again; the center line of the valve stem is not correct or the spring is rusted, so that the valve disc cannot be opened to the required level. For some heights, the valve stem should be reassembled or the spring should be replaced; if the exhaust pipe is not enough, an exhaust pipe that meets the safe discharge area should be adopted.
5. Frequent flapping or vibration of the valve clack: mainly due to too much spring stiffness. A spring with appropriate stiffness should be used instead; improper adjustment of the adjusting ring makes the return pressure too high. The position of the adjusting ring should be re-adjusted; the resistance of the discharge pipe is too large, resulting in excessive discharge back pressure. The resistance of the discharge pipe should be reduced. Opening under the specified pressure: Mainly because the constant pressure is not accurate; the spring is aging and the elastic force is reduced. The adjustment screw should be tightened properly or the spring should be replaced.