Safety valve:

Safety valve is the prescribed special valve that it is open-close part under the action of external force in a normally closed state, when the equipment or piping within the medium pressure than specified value, safety valve through a discharge medium system to prevent the pipeline or equipment within the medium pressure in excess.The safety valve is mainly used in boilers, pressure vessels and pressure piping, the safety valve's design, manufacture, installation, use, inspection and so on should comply with the relevant requirements,the control pressure shall not exceed the specified value,It is an important role to protect personal safety and equipment operation plays.

Common safety valve generally have the following kinds:
1. according to the safety valve gas emissions can be divided into fully enclosed and semi-enclosed and open.
2. according to the form of the overall structure and the load structure can be divided into weight load lever valve, spring-loaded safety valves and control type.
3. according to the disc type open height and diameter of valve circulation ratio can be divided into micro type and the safety valve.

Selection of safety valve:
1, The choice of emissions must be greater than the safety valve discharge capacity of equipment, which ensures that part of the medium are excluded, avoid pressure continues to rise.
2, Each safety valve has its own operating pressure range,the safety valve should be chosen according to the actual needs.
3. If the media toxic, flammable, safety valve should be selected Closed
4, The structure is depending on the process conditions and equipment working medium characteristics. General boilers and pressure vessels discharge capacity is not big in the cace thatalwanys choose spring-loaded safety valve, otherwise choose whole rev safety valve is better.