For equipment operating under pressure, leakage in excess of allowable levels occurs between the Gate Valve and the sealing valve seat. Cause: Dirt between the valve and valve seat sealing surfaces. When using a poppet valve, put the dirt and damage the sealing surface when the wrench is opened. Repair according to grinding or turning grinding method after a certain degree of damage; bend, tilt or tilt stem of lever and fulcrum, spool and valve position. The Gate Valve needs to be reinstalled or replaced because the spring elasticity has decreased or lost elasticity. Gate Valve return spring, and then take measures, such as adjusting the opening pressure.
Mainly because spring is too big. An adjustment ring should be used instead to adjust the spring with appropriate stiffness. The return pressure of the Gate Valve is too high. The position of the adjusting ring should be adjusted; the exhaust pipe resistance is too great and the Gate Valve causes excessive exhaust back pressure. Low discharge pipe resistance.
Adjusting the valve exhaust pressure and return pressure must reach the valve opening height for testing, therefore, it may only be performed on large-capacity testing equipment or when the relief valve is installed on protected equipment. Adjustment methods vary.
The Gate Valve retainer and valve seat adjustment ring of the Universal Valve structure are adjusted to the valve seat ring. To loosen the adjustment ring screw, use a thin wand-like tool from the exposed screw. You can drag the adjustment ring gear teeth to turn the adjustment ring left or right. When the adjustment ring is rotated counterclockwise to the left, its elevated position will reduce pressure and return pressure.
On the contrary, when the adjustment ring is rotated clockwise to the right, the lower exhaust pressure and back pressure must be increased. For each adjustment, the rotation range should not be too large (usually several teeth are rotated). After that, the adjustment screw should be tightened every time, so that the two teeth between the adjustment ring grooves can prevent the adjustment from ending the ring rotation without adjusting the radial pressure of the ring.