Double seal butterfly valve

Abstract

The invention relates to a butterfly valve for intercepting the flow of a medium on a pipeline, in particular to a double seal butterfly valve for effectively intercepting the flow of gas in a gas pipeline in the metallurgical industry. The valve comprises a valve body, a valve rod, a butterfly plate and a pressing plate, and is characterized in that: two sealing rings are fixedly arranged on the butterfly plate in the valve plate through the pressing plate; a support ring is arranged between the two sealing rings; an annular sealing cavity which can be filled with water or nitrogen is formed by the two sealing rings and a valve seat of the valve body; a channel is formed on the valve seat of the valve body, which corresponds to the sealing cavity; and a connecting pipe communicated with the channel is arranged on the valve body. The valve has the advantages that: the sealing cavity is filled with the water or nitrogen to form a closed sealing strip, so that micro leakage caused by long-time wear or corrosion of the sealing rings is avoided; a pressure transmitter accurately displays the sealing state of the valve, so that the damaged sealing ring is timely replaced; and sealing reliability and using safety are higher.

Description

technical field [0001] The invention relates to a butterfly valve for cutting off medium flow on a pipeline, in particular to a double-sealed butterfly valve for gas pipelines in the metallurgical industry to effectively cut off the flow of gas. Background technique [0002] At present, traditional metal-sealed butterfly valves or rubber-sealed butterfly valves are generally used in gas pipelines in the metallurgical industry, relying on the contact between the butterfly plate sealing ring and the valve seat of the valve body to achieve sealing. When there is a small leakage, the user cannot accurately judge the sealing performance of the valve after it is closed, which will easily cause gas poisoning and explosion accidents for the maintenance personnel on site. In severe cases, it will endanger life and bring huge losses to normal production. Therefore, the traditional sealing butterfly valve The seal is unreliable and unsafe to use. Contents of the invention [0003] T...

AI Technical Summary

Problems solved by technology

[0002] At present, traditional metal-sealed butterfly valves or rubber-sealed butterfly valves are generally used in gas pipelines in the metallurgical industry, relying on the contact between the butterfly plate sealing ring and the valve seat of the valve body to achieve sealing. When there is a small leakage, the user cannot accurately judge the sealing performance of the valve after it is closed, which will easily cause gas poisoning and explosion accidents for the maintenance personnel on site. In severe cases, it will endanger life and bring huge losses to normal production. Therefore, the traditional sealing butterfly valve Unreliable sealing, unsafe to use

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