Packing sealing structure of needle-shaped cutoff valve

Abstract

The invention relates to a packing sealing structure of a needle-shaped cutoff valve. An upper packing retaining gasket is further arranged between an upper packing press gasket and a packing, and a lower packing retaining gasket is further arranged between a lower packing press gasket and the packing. The packing sealing structure has the advantages that although a valve core part at the upper part of a valve flap is deflected due to the self-centering action, an inner hole of each packing retaining gasket is always tightly attached to the valve core part because of the certain elasticity of the corresponding retaining gasket, gaps between the valve core part of the valve flap and the upper packing retaining gasket as well as the lower packing retaining gasket are filled, and the peristalsis and outflow of the packing are prevented; as the peristalsis of each retaining gasket is small, the peristalsis and outflow loss of the packing is reduced; in addition, nonmetallic buffer zones are arranged between two metal parts, namely between the valve flap and the upper packing press gasket as well as the lower press gasket, by the retaining gaskets, so the hard abrasion between metals is avoided, and the surface smoothness of the valve core part is protected; when the valve core moves in the packing up and down, the abrasion on the packing is small, the leakage of the packing is avoided, and the service life of the packing is prolonged.

Description

technical field [0001] The invention relates to a shut-off valve, in particular to a stuffing sealing structure of a needle-shaped shut-off valve. Background technique [0002] The characteristics of the needle globe valve include simple structure, easy maintenance, and low manufacturing cost, etc., but the adjustment accuracy of the throttle valve is not high, and it is difficult to use it as a regulating valve. Cavitation is prone to occur, so parts need to use cavitation-resistant materials, and are not suitable for cutting off media. During the use of the needle globe valve, leakage often occurs due to the wear of the packing. Therefore, the sealing structure of the stuffing box of the needle globe valve needs to be analyzed and improved. [0003] Commonly used needle globe valves, when the main sealing surface of the valve is sealed, the sealing cone surface of the lower part of the valve disc must be concentric with the valve core part of the upper part of the valve ...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to provide a packing sealing structure of a needle stop valve, which solves the problem that the existing needle stop valve has the problem of leakage of packing due to the gap between the packing pressure pad and the valve core support and reduces the service life.

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