900 Series DIN Spring loaded Pressure Safety Valve 

900 Series DIN Spring loaded Pressure Safety Valve 

Safety valves were first used on steam boilers during the industrial revolution. Early boilers without them were prone to accidental Explosion.
Safety valves also evolved to protect equipment such as pressure vessel (fired or not) and heat exchangers. Safety valve term should be limited to compressible fluid application (gas, vapor, steam).

The two general types of protection encountered in industry are thermal protection and flow protection.

For liquid-packed vessels, thermal relief valves are generally characterized by the relatively small size of the safety valve necessary to provide protection from excess pressure caused by thermal expansion. In this case a small valve is adequate because most liquids are nearly incompressible, and so a relatively small amount of fluid discharged through the relief valve will produce a substantial reduction in pressure.

DIN Standard Safety Valve Specification

safety valve, pressure relief valve, safety relief valve, safety valve temperature, high temperature safety valve, high pressure safety valve. 

1. ARI 902 DIN Spring loaded Pressure Safety Valve: 

2.A46F/H/Y Pilot-operated Pressure Relief valve (A46 Safety Valve):

3.Double Port High Lift Safety Valve:

4.A21 Spring loaded low lift external thread type safety valve:

5.A27Spring loaded low lift type safety valve: 

 6A41Closed spring loaded low lift type high pressure safety valve:

7.A48Spring loaded ful lift safety valve: 

8.A44Spring loaded Full Lift safety valve:

9.A37、A38、A43Twin spring type safety valve:

 10.A48SB High temperature and high pressure safety valve: 

11.GA49H Impulse Safety Valve  

 12.A42Y-160/320Closed spring loaded full bore type high pressure safety valve  

13.A42 Closed spring loaded full lift type safety valve

14.Lever Saety Valve

15.W Series Spring Loaed Full Lift Safety Valve 

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