At present, China's boiler room commonly used in industrial boiler safety valve are: lever, spring, static weight, pulse and a variety of complex.
Lever boiler safety valve
Lever type safety valve is divided into single lever and double lever two. They are also known as heavy hammer safety valves because they balance the pressure of the steam (water) by acting on the spool through the moment of leverage and weight.
Lever (hammer type) safety valve mainly by the valve core, seat, lever, hammer, limit devices and other components. It is the weight of the hammer, through the lever to the spool on the valve seat, move the weight of the position to change the size of the weight moment to adjust the relief valve opening pressure. When the boiler pressure exceeds the pressure at the top of the spool, the spool is lifted off the seat and the steam is vented. When the boiler pressure is lower than the pressure at which the hammer acts on the top of the valve plug, the valve spool falls and the boiler stops exhausting.
This safety valve structure is simple, easy to adjust, reliable performance, so the boiler is quite common. General single lever safety valve for low pressure boilers, double lever safety valve for medium and high pressure boilers.