Methods to resolve safety valve failures

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1. Leakage: At the normal operating pressure of the equipment, leakage occurs between the valve disc and the valve seat sealing surface in an amount that exceeds the allowable limit. The reasons include: there is dirt between the valve disc and the valve seat sealing surface. The valve can be opened several times using a lift wrench to flush out the dirt ； Damage to the sealing surface. Depending on the degree of damage, repair should be carried out by grinding or by grinding after turning ； The valve stem is bent, tilted, or the lever is offset from its pivot point, causing the valve core and valve disc to be out of alignment. It should be reassembled or replaced ； The spring loses its elasticity or its resilience decreases. Measures such as replacing the spring and readjusting the opening pressure should be taken. 2. It does not open when the specified pressure is reached; the reason for this is inaccurate pressure setting. The compression amount of the spring or the position of the weight should be adjusted again ； The valve disc is stuck to the valve seat. The safety valve should be regularly tested for manual venting or water discharge ； The lever of the lever-type safety valve is stuck or the weight has been moved. The position of the weight should be readjusted to allow the lever to move freely. 3. Failure to open at the specified pressure is mainly due to inaccurate pressure setting ； The spring loses its elasticity as it ages. The adjustment screw should be tightened properly or the spring replaced. 4. The pressure continues to rise after exhaust. This is mainly because the safety valve selected has a low discharge capacity, resulting in an insufficient amount of pressure relief for the equipment; a suitable safety valve should be chosen instead ； If the valve stem is not aligned properly or the spring is rusted, preventing the valve disc from reaching its proper height, the valve stem should be reassembled or the spring replaced ； The exhaust pipe is not long enough; an exhaust pipe that meets the requirements for safe exhaust area should be used. 5. Frequent jumping or vibration of the valve disc is mainly due to excessive spring stiffness. A spring with appropriate stiffness should be used instead ； The adjustment ring is not set properly, resulting in excessive reseating pressure. The position of the adjustment ring should be readjusted ； The resistance in the exhaust pipeline is too high, resulting in excessive exhaust backpressure. The resistance of the exhaust pipeline should be reduced. 6. The valve disc does not return to its original position after discharge. This is mainly caused by the spring bending the valve stem, the valve disc being installed in the wrong position, or it getting stuck. It should be reassembled