Metal valve seat sealing structure for cryogenic butterfly valve under ultralow temperature working condition

Abstract

The invention relates to a metal valve seat sealing structure for a cryogenic butterfly valve under an ultralow temperature working condition. The structure comprises a valve body, a valve plate, and a valve cover arranged on the valve body, wherein a transmission shaft is arranged in a shaft hole of the valve body; the valve plate is arranged in an inner hole of the valve body; and a retainer is arranged between the valve plate and the valve body. The structure is characterized in that: an inner side O-ring and an outer side O-ring are fixed between the retainer and the valve body; the inner side O-ring is pressed on the valve plate by a positioning ring; each of the outer side O-ring and the inner side O-ring comprises an outer metal layer and a spring coated in the metal layer; the inner side O-ring is in seamless connection with the outer side O-ring; the positioning ring is pressed on the valve body through a pressing ring; and the spring is made of a nickel-chromium alloy material. The structure still can keep high elasticity in a -254 DEG C ultralow temperature environment; the inner side O-ring is in seamless connection with the outer side O-ring, so that a medium is prevented from leaking from the positioning ring; and the service life of the valve is effectively prolonged, maintenance cost is reduced, and economic benefits are improved.

Description

technical field [0001] The invention relates to a valve seat sealing structure, in particular to a metal valve seat sealing structure for a cryogenic butterfly valve under ultra-low temperature conditions. Background technique [0002] With the development of the economy, the requirements for the level of industrial automation control are constantly increasing, and the working conditions faced by the valves are also more complex and harsh. Butterfly valves have become one of the mainstream control devices in industrial process control, which puts forward higher requirements for the sealing performance of butterfly valves under ultra-low temperature (such as air separation) conditions. In the prior art, traditional metal-sealed butterfly valves use an elastic metal ring formed by stamping or turning of ordinary stainless steel as the valve seat, which cooperates with the valve plate to achieve sealing. Due to the severe cold and brittle phenomenon of stainless steel under ul...

AI Technical Summary

Problems solved by technology

Due to the severe cold and brittle phenomenon of stainless steel under ultra-low temperature conditions, it loses the elasticity required for effective sealing. Therefore, it is determined that the metal-sealed butterfly valve with traditional structure cannot adapt to the ultra-low temperature working environment, and it is prone to failures such as sealing failure and internal damage. The reliability and stability of the system cannot be guaranteed, threatening the normal operation of the entire system, and even causing huge economic losses

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