The safety valve is a security valve, its opening and closing parts of the external force is normally closed state, the media pressure when the equipment or piping, open automatically when you exceed the specified value, emissions of media outside the system to prevent medium pressure piping or equipment exceeds the set value. The safety valves are automatic valves used in boilers, pressure vessels and piping, control pressure does not exceed the specified value, play an important protective effect on personal safety and equipment operation. 
 The valve structure has two categories: spring and leveraged. Spring-loaded valves and valve seat seal by a spring force. Leveraged by the force of the lever and hammer. With the large capacity needs, have a pulse valve, also known as pilot safety valve, the main valve and auxiliary valve. When the pipe medium pressure exceeds the set pressure value, the auxiliary valve first opens, the media along the catheter into the main valve and main valve to open, the increased media pressure is reduced. 
 Safety valve emissions determines the opening height, diameter and valve seat can be divided into two types: inching opening height of the seat inner diameter (1/15) - (1/20), full-Kai (1/3) ~ (1/4). 
 In addition, with the different application requirements, closed and not closed. Closed-discharge media is not compromised, all along the required exit discharge, generally used for toxic and corrosive media. Not closed in general for non-toxic or non-corrosive media. 
 Deng Yang valve safety valve products are: (K) AF46Y pilot safety valve, 900 German standard safety valve, the A21F spring of Weiqi outside thread safety valve, A28H spring safety valve, A28W-10T Copper a closed safety valve of the safety valve, A37H, A43H double spring-loaded safety valve, A38Y double spring-loaded safety valve, A41H (Y) spring Enlight, A41Y-160 spring Enlight closed pressure safety valve, A41Y-320 spring the Enlight closed high pressure safety valve, A42Y-1000 full-Kai ultra-high pressure safety valve, A42Y spring full-Kai closed safety valve A42Y spring Kai closed pressure safety valve, A44Y for, A48Y the boiler safety valve, with a wrench A44Y Spring safety valve, A47H (Y) Weiqi safety valve with a wrench spring, A48Y safety valve with a wrench spring, A49H-4 main safety valve, the A49H high temperature high pressure main valve A49Y-10 temperature, pressure impulse safety device A49Y spring safety valve (pulse), A61Y-320P spring inching a safety valve, liquefied petroleum gas safety valve in AH42F parallel AHN42F-P18 safety valve, the AQ series air compressor safety valve AY42H safety overflow valve pulse valve GA49H SANA42F built-in safety valve, vacuum relief valve in SFA72W-10P, WA42Y bellows balanced safety valve YA40Y with a safety valve of the radiator springs YFA72W vacuum relief valve, single-lever safety valves, springs the Enlight closed high pressure safety valve spring inching valve