Safety valve selection principles

Thread Content

Principles for selecting safety valves 1. For steam boiler safety valves, open full-lift spring safety valves are generally used.； 2. For safety valves used for liquid media, micro-opening spring safety valves are generally used. ； 3. Safety valves for air or other gas media generally use closed full-open spring safety valves. ； 4. Safety valves for LPG truck tankers or LPG railway tankers generally use full-open built-in safety valves. ； 5. For safety valves at the outlet of oil production wells, pilot-operated safety valves are generally used. ； 6. For high-pressure bypass safety valves of steam power generation equipment, pilot-operated safety valves with dual functions of safety and control are generally selected. 7. If regular opening tests of the safety valve are required, a safety valve with a lifting wrench should be selected. When the medium pressure reaches more than 75% of the opening pressure, the lift wrench can be used to slightly lift the valve disc from the valve seat to check the flexibility of the safety valve opening. ； 8. If the medium temperature is high, in order to reduce the temperature of the spring chamber, generally when the operating temperature of the closed safety valve exceeds 300°C and the operating temperature of the open safety valve exceeds 350°C, a safety valve with a radiator should be selected ； 9. If the outlet back pressure of the safety valve changes and the change exceeds 10% of the opening pressure, a bellows safety valve should be selected. ； 10. If the medium is corrosive, a bellows safety valve should be used to prevent important parts from failing due to corrosion by the medium.