The pipeline pressure has increased; can the safety valve still be used?
Thread Content
The pipeline was originally designed for a pressure of 1.3 Mpa; now it is desired to increase this pressure to 1.7 Mpa. Can the original safety valves still be used? If so, what actions are required? The process calculations indicate that the requirements can be met – is it still necessary to have it inspected and verified by a testing agency?
Check the model of the safety valve; if the pressure is within the specified range, it can continue to be used – it only needs to be sent for re-calibration
This post was last edited by Chow Tai Fook on 2015-10-30 at 11:12. The design pressure of the pipeline has been increased to 1.7 MPa; it is necessary to check the parameters of the original safety valve. Safety valve models are classified into different grades and can be adjusted within a certain range; ultimately, they need to be tested and verified by a certified testing agency. It is recommended that you take a look at TSG ZF001-2006 \"Regulations on Safety Technical Inspection of Safety Valves\".
In a situation like yours, it’s necessary to replace the safety valve or the spring. The appropriate range for the spring pressure levels in our company is 0.3–0.7, 0.7–1.0, 1.0–1.3, 1.3–1.6, and 1.6–2.0. It seems that your existing spring was designed for a pressure range of 1.3–1.6. Since your current pressure is 1.7 Mpa, and the set pressure should be 1.1 times the maximum operating pressure, you need to use a spring with a pressure range of 1.6–2.0
It depends on the set pressure of the safety valve you selected initially; generally, however, the safety valve is chosen based on the design pressure, and in that case it needs to be replaced
Changing the design pressure requires documentation; whether a safety valve needs to be replaced depends on the discharge volume and the pressure rating of the safety valve.