How Do You Adjust the Pressure On a Safety Valve?
What is the working principle of the safety valve?
How Do You Adjust the Pressure On a Safety Valve?
1. Before the safety valve leaves the factory, we should adjust its opening pressure to reach the set value user specifies. If a user specifies the working pressure level of the spring, then we should adjust it according to the lower limit of the pressure level.
2. Before the safety valve is installed on the protected equipment, users must re-adjust it at the installation site to ensure the set pressure value of the safety valve meets the requirements.
3. In the range of the working pressure level of the spring specified by the nameplate, by turning the adjustment stem to change the compression amount of the spring, we can adjust the opening pressure.
4. Before turning the adjustment stem, make sure the inlet pressure of sanitary valve is reduced to less than the opening pressure to prevent the valve flap from being turned when adjusting the stem, damaging the sealing surface.
5. To ensure the accuracy of opening pressure value, make sure the medium conditions, such as medium types and temperatures, are as close as possible to the actual operating conditions. When the medium type changes, especially when the dielectric aggregation is different (for example, from the liquid phase to the gas phase), the opening pressure often changes. When the operating temperature rises, the opening pressure is generally reduced. When it’s adjusted at room temperature and used for high temperature, the set pressure value at room temperature should be slightly higher than the required opening pressure value. How high the temperature should be has something to do with the valve structure and material selection, so it should be based on the manufacturer’s instructions.
6. The conventional safety valve is used to fix the additional backpressure. When adjusting opening pressure after the testing (at this time, the backpressure is atmospheric pressure), the set value should be required opening pressure minus additional backpressure.
Conclusion
By adding the 0.1 bar shut-off margin, the safety valve set pressure has to be 10% greater than 6.4 bar. For this example, this means that the safety valve’s set pressure has to be: The set pressure would therefore be chosen as 7.11 bar, provided that this does not exceed the MAWP of the protected system.
Thank you for reading our article and we hope it can help you better understand the adjustment of the opening pressure of the safety valve. If you want to learn more about safety valves, we would like to advise you to visit Adamant Valve homepage for more information.
