Bidirectional hard-seal butterfly valve

Abstract

The invention relates to a bidirectional hard-seal butterfly valve. The valve comprises a valve body, a valve seat, a butterfly plate and a valve rod. The butterfly plate is provided with a conical metal seal surface; the valve seat adopts a flexible self-sealing valve seat mainly, the flexible self-sealing valve seat is composed of an arc-shaped metal seal ring, the arc-shaped metal seal ring isembedded in the inner wall of a valve body channel, the left end of the arc-shaped metal seal ring is provided with a left circular-arc surface, and the right end of the arc-shaped metal seal ring isprovided with a right circular-arc surface; the left circular-arc surface abuts against a right angle between the inner wall of the valve body channel and a first radial step of the inner wall of thevalve body channel, and the right circular-arc surface abuts against an axial pressing device; and a strengthening ring is mounted in a circular-arc cavity formed by the arc-shaped metal seal ring andthe inner wall of the valve body channel, a positioning spring is arranged on a surface where the strengthening ring makes contact with the inner wall of the valve body channel, and a circular-arc surface is arranged on the side, facing the arc-shaped metal seal ring, of the strengthening ring. By means of elastic energy storage and deformation of the arc-shaped metal seal ring, thermal expansionand chilling contraction caused by abrasion of the seal surface and variation of the temperature are automatically compensated. The bidirectional hard-seal butterfly valve has the characteristics ofbeing reliable in sealing performance, long in product service life, resistant to high temperatures and abrasion and the like.

Description

Technical field [0001] The invention belongs to the field of valves, and particularly relates to a hard-sealed butterfly valve. Background technique [0002] Butterfly valve has the characteristics of simple structure, convenient opening and closing, low manufacturing cost, etc., and is widely used in the medium transportation pipeline system of various industries in the national economy. The triple eccentric butterfly valve is currently the most common butterfly valve structure design due to its high sealing specific pressure. Its structure includes valve body, valve seat, butterfly plate, and valve stem. In the high temperature and abrasive medium transportation pipeline, the butterfly valve is required to have high temperature resistance and wear resistance. The butterfly plate and the valve seat are generally matched with a hard seal. At present, the seat sealing surface of hard-sealed butterfly valves is generally processed directly in the valve body passage. Because the se...

AI Technical Summary

Problems solved by technology

At present, the seat sealing surface of hard-sealed butterfly valves is generally directly processed in the valve body channel. Since the seat sealing surface is an oblique cone structure, the processing technology is relatively complicated, and both the seat sealing surface and the butterfly plate sealing surface are processed. There is always a matching error between the sealing surfaces after the two cooperate with each other, resulting in poor sealing performance of the existing hard-sealed butterfly valve

Moreover, during use, friction occurs between the sealing surface of the valve seat and the sealing surface of the butterfly plate, causing irreversible wear on the sealing surface, resulting in a decrease in the sealing performance of the sealing pair and a short service life of the product

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