Analysis of Causes for Safety Valve Leakage

Causes of safety valve leakage
a. Damage to the sealing surface of the safety valve seat or disc
The reasons for damage to the sealing surface may be caused by the erosion of the metal sealing surface by corrosive media; it may also be that during the installation of the safety valve, dirt is brought into the valve inlet chamber or sealing surface, and electric welding slag, rust and various solid substances mixed in the medium left in the safety valve inlet pipeline or equipment during equipment installation.

The scratches caused by the scouring of the sealing surface by the high-speed medium flow rate when the safety valve is discharged.
b. Caused by improper installation of safety valve
Improper installation mainly refers to leakage caused by damage or deformation of the valve coaxiality due to the uneven load formed by the incorrect installation of the safety valve inlet and outlet connecting pipes.
c. Caused by high temperature of safety valve
For safety valves used in high-temperature media or installed in high-temperature environments, uneven thermal expansion may occur around the surfacing layer of the valve seat or valve core sealing surface, and the stiffness of the spring becomes softer after being heated, the preload is reduced, and the sealing specific pressure is decreased, resulting in leakage..
d. Improper selection of safety valve
When the opening pressure of the selected safety valve is too close to the actual working pressure of the equipment, due to the fluctuation range of the working pressure of the equipment being close to or exceeding the sealing pressure of the safety valve, it may also cause leakage of the valve.
e. Dirt on the safety valve is sandwiched on the sealing surface
Due to improper assembly, the sealing surface is sandwiched with dirt or the dirt in the equipment and management is sandwiched on the sealing surface, etc., which will cause the valve to leak due to poor sealing.