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Safety valve is a special valve whose opening and closing parts are normally closed under the action of external force. When the medium pressure in the equipment or pipeline rises above the prescribed value, it can prevent the medium pressure in the pipeline or equipment from exceeding the prescribed value by discharging medium into the system.

Safety valves belong to automatic valves. They are mainly used in boilers, pressure vessels and pipes. The control pressure does not exceed the prescribed value, which plays an important role in protecting personal safety and equipment operation. The injection safety valve must undergo pressure test before it can be used.