12-17 What are the provisions for the pressure setting of the safety valve of pressure vessels in the "Regulations on Safety Technical Supervision of Pressure Vessels"?

Answer: (1) When only one safety valve is installed on a fixed pressure vessel, the opening pressure P_Z of the safety valve should not be greater than the design pressure P of the pressure vessel, and the sealing test pressure P_t of the safety valve should be greater than the maximum working pressure P_W of the pressure vessel.

(2) When multiple safety valves are installed on a fixed pressure vessel, the opening pressure of one safety valve should not be greater than the design pressure of the pressure vessel, and the opening pressure of the remaining safety valves can be appropriately increased, but shall not exceed 1.05 times the design pressure.

(3) The opening pressure of the safety valve of a mobile pressure vessel should be 1.05~1.10 times the design pressure of the tank body, the rated discharge pressure of the safety valve shall not be higher than 1.2 times the design pressure of the tank body, and the return pressure shall not be lower than 0.8 times the opening pressure.