Adjustment of opening pressure of Globe Valve

1. Before the Globe Valve leaves the factory, its opening pressure should be adjusted one by one to the setting value required by the user. If the user proposes a spring working pressure level, the factory adjustment should generally be made according to the lower limit of the pressure level.

2. Before installing the Globe Valve to the protected equipment or before installation, the user must readjust it at the installation site to ensure that the set pressure value of the Globe Valve meets the requirements.
3. Within the spring working pressure level range indicated on the nameplate, the opening pressure can be adjusted by rotating the adjustment screw to change the spring compression amount.
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 the adjusting screw is rotated, thereby damaging the sealing surface.
5. In order to ensure the accuracy of the opening pressure value, the medium conditions during adjustment, such as medium type, temperature, etc., should be as close as possible to the actual operating conditions. The opening pressure often changes when the type of medium changes, especially when the accumulation state of the medium is different (for example, from liquid phase to gas phase). As the operating temperature increases, the cracking pressure generally decreases. Therefore, when adjusting at normal temperature and using it at high temperature, the set pressure value at normal temperature should be slightly higher than the required opening pressure value. How high it is is related to the structure and material selection of the Universal Valve, and should be based on the manufacturer's instructions.
6. Conventional Globe Valve are used when additional back pressure is fixed. When the opening pressure is adjusted after inspection (the back pressure is atmospheric pressure at this time), its setting value should be the required opening pressure value minus the additional back pressure value.