Rotary four-eccentricity ball valve

Abstract

The invention discloses a rotary four-eccentricity ball valve which comprises a valve body, an upper valve rod, a lower valve rod, a ball body, valve seats, bearings, springs, sealing rings and packing seal structures and is a rotary ball valve. The ball body is located in the valve body. The springs are arranged between the ball body and the valve seats. The valve body is provided with an end cover and a bottom cover. The valve body and the two valve seats are connected through threads. The valve rods and the ball body are also connected through threads. The sealing rings are arranged between the ball body and the valve body. The packing seal structures are arranged between the valve rods and the valve body. According to the ball valve, four eccentricity distances exist and include contact eccentricity between the centers of the valve rods and the sealing surfaces, eccentricity between the centers of the valve rods and the center of the valve body, angle eccentricity for perpendicularity of the sealing contact surfaces to the center of a valve body channel, and eccentricity which is formed between the rotation centers of the valve seats and the plain lines of the cross sections of the sealing surfaces of the valve seats and enables the engagement angle of the ball body to be adjustable. The ball valve can reduce abrasion between sealing pairs and reduce opening and closing torque, and the life of the ball valve is prolonged.

Description

technical field [0001] The invention belongs to the technical field of agricultural machinery and relates to a four-eccentric ball valve, in particular to an eccentric ball valve with the characteristics of reducing wear between sealing pairs, reducing opening and closing torque, and improving the service life of the ball valve. Background technique [0002] Due to good sealing and flow characteristics, ball valves are widely used in some industries, such as paper making, natural gas, high pressure fields, etc. The ball valve is evolved from the plug valve. Its opening and closing part is a sphere. The ball is rotated 90° around the axis of the valve stem to realize the opening and closing of the valve, which can cut off, distribute and change the flow direction of the medium. Compared with butterfly valves, ball valves have the lowest flow resistance and good sealing performance. They can be used in corrosive media and low-boiling liquids to achieve rapid opening and closin...

AI Technical Summary

Problems solved by technology

In summary, although the existing eccentric ball valves have been further improved, there are still certain problems in terms of pressure and temperature.

[0004] The material of the seat seal ring of the ball valve is mainly polytetrafluoroethylene. Since polytetrafluoroethylene has the characteristics of high expansion coefficient, sensitivity to cold flow and poor thermal conductivity, these must be considered in the design of the seat seal. Factors, which makes the design of ball valves also have certain problems

[0005] In summary, the ball valves in the prior art have problems such as serious wear, high pressure, and poor sealing performance.

Images