Safety valve calculation
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When calculating safety valves, what overload limit is entered? What value do everyone use? If the design pressure is taken as 2.3 MPa, and according to GB150 B4.2.1, 10% of the design pressure should be used, which would be 0.23 MPa. This means that the discharge pressure of the safety valve is 2.3 MPa. However, in P135, PD is defined as including both the design pressure and the overpressure limit (see B4.2.1). Can it be understood here that the discharge pressure PD = P + △P? Are these two things contradictory these days? Please ask an expert for help
I didn’t quite understand, but it shouldn’t be contradictory, right? The design pressure of the safety valve (i.e., the setting pressure) is less than or equal to the design pressure of the container ； The overpressure limit of the container is less than or equal to 10% of the design pressure ； The discharge pressure of a safety valve is generally set at 105% to 110% of the design pressure; I recall that different standards require different values, but in any case the discharge pressure specified by safety regulations is always lower than the overpressure limit of the container.
The opening pressure of a safety valve is generally 1.05 to 1.1 times the operating pressure of the container, as clearly specified in GB150