Improved method and structure of plug valve

Abstract

The invention discloses an improved method and structure of a plug valve. A position-limiting boss is arranged at the orifice of an operation hole of a valve body, and meanwhile an arc-shaped position-limiting groove is formed in an operation key; the operation key can only rotate within a range of 90 degrees through the rotary cooperation of the position-limiting boss and the arc-shaped position-limiting groove; meanwhile a beeline-shaped convex key is arranged on the operation key and is connected to a key groove in a ball core to jointly realize the plug valve opening and closing function;a spacing ring is arranged at the bottom of the operation key so as to prevent the operation key from being pushed out of the operation hole by water pressure in a water flow channel; and the bottom of the operation key is connected to the key groove in the ball core by the beeline-shaped convex key, thus, the plug valve structure is simplified, and the reliability of the plug valve is improved. The operation key of the plug valve is of an overall structure; the structure is simple; few parts are used; the processing difficulty is reduced; the strength of the valve body is improved; the problem of stress concentration of the plug valve caused by severe working conditions under a shaft is effectively solved; the risk of the plug valve fracture under the shaft can be avoided; and the cost performance of the product is improved.

Description

technical field [0001] The invention relates to an improved method and structure of a plug valve, belonging to the technical field of ball valve structures. Background technique [0002] As a kind of anti-blowout ball valve in the drilling tool, the plug valve has been widely used in drilling and workover construction operations at home and abroad, and is used to block or connect the liquid in the water flow channel of the drill string. During normal drilling, the drilling fluid enters the drill string by opening the cock valve, and closing the cock valve when connecting a single root can prevent the drilling fluid from splashing on the well platform, which not only avoids the waste of drilling fluid, but also meets the environmental protection requirements; Closing the plug valve in time during accidents such as blowout and blowout can prevent combustible gas or liquid from overflowing the wellhead, causing casualties and property losses. The stress concentration fracture ...

AI Technical Summary

Problems solved by technology

During normal drilling, the drilling fluid enters the drill string by opening the cock valve, and closing the cock valve when connecting a single root can prevent the drilling fluid from splashing on the well platform, which not only avoids the waste of drilling fluid, but also meets the environmental protection requirements; Closing the plug valve in time during accidents such as blowout and blowout can prevent combustible gas or liquid from overflowing the wellhead, causing casualties and property losses. The stress concentration fracture caused by the groove in the valve body hole of the plug valve, the operation key is a combined structure, the structure of the upper and lower ball seats is not uniform, there are many parts, the structure is complicated, it is inconvenient to disassemble and assemble, time-consuming and laborious, and the pressure test is unstable.

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