Operation Method of Safety Valve

Adjustment of opening pressure:

 ① Before the safety valve leaves the factory, its opening pressure shall be adjusted one by one to the setting value required by the user. If the user proposes the working pressure level of the spring, it shall be adjusted according to the lower limit of the pressure level.

 ② Before installing the safety valve on the protected equipment or before installation, the user must readjust it on the installation site to ensure that the set pressure value of the safety valve meets the requirements.

 ③ Within the range of spring working pressure level indicated on the nameplate, the opening pressure can be adjusted by rotating the adjusting screw to change the spring compression.

 ④ Before rotating the adjusting screw, the valve inlet pressure should be reduced to less than 90% of the opening pressure to prevent the valve disc from being driven to rotate when rotating the adjusting screw, resulting in damage to the sealing surface.

 ⑤ In order to ensure the accuracy of the opening pressure value, the medium conditions during adjustment, such as medium type and temperature, should be as close to the actual operating conditions as possible. The type of medium changes, especially when the accumulation state of the medium is different (for example, from liquid phase to gas phase), the opening pressure often changes. When the working temperature increases, the opening pressure generally decreases. Therefore, when it is adjusted at room temperature and used at high temperature, the set pressure value at room temperature should be slightly higher than the required opening pressure value. How high is related to the valve structure and material selection, which should be based on the manufacturer’s instructions.

 ⑥. When the conventional safety valve is used to fix additional back pressure, the setting value should be less than the required back pressure when the opening pressure is adjusted after testing.


Post time: Feb-12-2022