The tightness of the gas ball valve

　　 There is a relatively common valve in natural gas pipelines. Due to its special application occasions, gas ball valves have relatively high requirements for sealing performance. How does it specifically ensure its sealing performance?

　　 In the structural design of its valve seat in a gas ball valve, there are generally two ways, the downstream valve seat self-discharging design and the double piston effect design. For a valve seat design, in its closed state, when its pipeline pressure acts on the outer surface of its upstream valve seat ring, it will press its valve seat against its ball, and if the medium leaks from its upstream to its valve cavity Internally, when the internal pressure of the valve cavity is higher than its downstream pipeline pressure, the relevant valve seat downstream will press its valve cavity pressure to its downstream to release it. If it is the second form of valve seat, under normal circumstances, its pressure is acting on the outside of the end of the valve seat sealing ring, which will press the sealing ring against the valve body to produce corresponding squeezing force, so that it can be A relatively reliable sealing structure is formed between the sealing ring and the valve body.

Even when the valve seat has leaked, its pressure will directly enter the valve body and act directly on the inner side of its upstream sealing surface, and exert a squeezing force on the valve seat sealing ring to make the valve seat The sealing ring slowly approaches the valve body to form a more reliable and effective sealing structure to ensure its sealing performance.