Screwing type plug valve

Abstract

The invention provides a screwing type plug valve which comprises a valve body, a plug cock, a left plug tile, a right plug tile, a valve cover, a sealing ring, a hand wheel, a cap, an upper combined seal and a lower combined seal, the plug cock is arranged in the valve body, the plug tiles are arranged between the plug cock and the valve body, the valve cover fixed to the valve body is arranged at the upper end of the plug cock, and the sealing ring is arranged between the valve cover and the valve body. The upper end of the valve cover is provided with a hand wheel fixed on the cock through a cap, a lower combined seal is arranged between the lower end of the cock and the valve body, and an upper combined seal is arranged between the upper end of the cock and the valve cover. The cock is provided with two semi-cylindrical sealing surfaces which are parallel to the axis of the cock and rotate around the cock shaft in the radial direction, the rotating radiuses of the two semi-cylindrical sealing surfaces are gradually increased or decreased, and the plug tile is provided with tile sealing surfaces corresponding to the semi-cylindrical sealing surfaces of the cock. The plug valve is reasonable in structure, it is effectively guaranteed that the plug valve is not prone to being abraded and stuck in the opening and closing process, the sealing performance is good, the working reliability is improved, and the service life is prolonged.

Description

Technical Field

[0001] The invention relates to a valve, in particular to a screw-on plug valve. Background Art

[0002] At present, plug valves have been widely used in the petroleum, chemical, electric power, metallurgy, papermaking and other industries. Traditional plug valves generally use cylindrical seals and are composed of a valve body, a plug, a plug shoe, a valve cover and a handwheel. When in use, the plug is driven to rotate by turning the handwheel above the plug, so that the through hole on the plug corresponds to or staggers with the flow channel of the valve, thereby realizing the opening or closing of the plug valve. Since the plug generates friction with the plug shoe during the rotation process, it is severely worn and easily stuck, making the plug unable to rotate, and the seal is not tight, which is easy to cause leakage, reducing the working reliability of the plug valve and shortening the service life of the plug valve. Although there are plug valves that are not easy to wear and not easy to get stuck, their structures are relatively complex and inconvenient to use and maintain. Summary of the invention

[0003] In order to overcome the deficiencies of the prior art, the present invention provides a screw-on plug valve which has a reasonable structure, is not prone to wear and jamming between the plug and the plug shoe, is easy to use and maintain, has good sealing performance and a long service life.

[0004] The technical solution adopted by the present invention to solve its technical problem is: comprising a valve body, a plug, a left plug shoe, a right plug shoe, a valve cover, a sealing ring, a hand wheel, a cap, an upper combined seal, a lower combined seal, a plug with a through hole is arranged in the valve body, a left plug shoe and a right plug shoe with a through hole are arranged between the left and right sides of the plug and the valve body, the axis of the through hole of the left plug shoe and the right plug shoe coincides with the axis of the flow channel hole of the valve body, a valve cover fixed to the valve body is arranged at the upper end of the plug, a sealing ring is arranged between the valve cover and the valve body, and a valve cover fixed to the valve body by the cap is arranged at the upper end of the valve cover A handwheel is fixed on the plug, a lower combined seal is provided between the lower end of the plug and the valve body, and an upper combined seal is provided between the upper end of the plug and the valve cover; it is characterized in that: on the plug, on both sides of the axis of the plug through hole, there are provided two semi-cylindrical sealing surfaces parallel to the plug axis, radially rotating around the plug axis, and formed by gradually increasing or decreasing the rotation radius; on the left plug valve and the right plug valve, on the inner side of the left plug valve and the right plug valve, there are left plug valve and right plug valve sealing surfaces corresponding to the semi-cylindrical sealing surfaces of the plug.

[0005] The semi-cylindrical sealing surface on the above-mentioned plug is parallel to the axis of the plug, or is not parallel to the axis of the plug.

[0006] The angle of radial rotation of the semi-cylindrical sealing surface on the above-mentioned plug around the plug axis is 180 degrees, or greater than 180 degrees, or less than 180 degrees.

[0007] The cock is provided with two semi-cylindrical sealing surfaces or a cylindrical sealing surface.

[0008] The two semi-cylindrical sealing surfaces on the plug rotate radially around the axis of the plug, and are formed by the rotation radius gradually increasing or decreasing, or are two semi-cylindrical sealing surfaces radially offset with the axis of the plug as the center.

[0009] The two semi-cylindrical sealing surfaces that rotate radially around the axis of the plug and are formed by the rotation radius gradually increasing or decreasing rotate in the clockwise direction or in the counterclockwise direction.

[0010] The structure of the present invention is reasonable, effectively ensuring that the sealing surface of the plug valve is not easily worn or stuck during the opening and closing processes, and has good sealing performance, thereby improving the working reliability of the plug valve and extending the service life of the plug valve. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 is a schematic structural diagram of the present invention;

[0012] Figure 2 is a schematic structural diagram of the plug in the present invention;

[0013] Figure 3 is Figure 2 a cross-sectional view taken along the line A-A in

[0014] Figure 4 is a schematic structural diagram of the left plug washer in the present invention;

[0015] Figure 5 is a schematic structural diagram of the right plug washer in the present invention;

[0016] Figure 6 is Figure 4 a cross-sectional view taken along the line D-D in

[0017] Figure 7 is Figure 5 a cross-sectional view taken along the line E-E in

[0018] Figure 8 is a schematic structural diagram of the plug, the left plug washer and the right plug washer after the valve in the present invention is opened;

[0019] Figure 9 is Figure 8 a cross-sectional view taken along the line B-B in

[0020] Figure 10 is a schematic structural diagram of the plug, the left plug washer and the right plug washer after the valve in the present invention is closed;

[0021] Figure 11 is Figure 10 a cross-sectional view taken along the line C-C in

[0022] In the figure: 1 is the valve body, 2 is the left plug, 3 is the valve cover, 4 is the handwheel, 5 is the union nut, 6 is the plug, 7 is the sealing ring, 8 is the right plug, 9 is the upper combined seal, 10 is the lower combined seal, 11 is the sealing surface of the left plug, 12 is the semi-cylindrical sealing surface, 13 is the sealing surface of the right plug.

[0023] Specific implementation method

[0024] The present invention will be further described in detail below with reference to the accompanying drawings.

[0025] The present invention includes a valve body 1, a plug 6, a left plug 2, a right plug 8, a valve cover 3, a sealing ring 7, a handwheel 4, a union nut 5, an upper combined seal 9, a lower combined seal 10. A plug 6 with a through hole is provided in the valve body 1. Between the left and right sides of the plug 6 and the valve body 1, there are a left plug 2 and a right plug 8 with through holes. The axes of the through holes of the left plug 2 and the right plug 8 coincide with the axis of the flow passage hole of the valve body 1. The upper end of the plug 6 is provided with a valve cover 4 fixed to the valve body 1. A sealing ring 7 is provided between the valve cover 4 and the valve body 1. The upper end of the valve cover 4 is provided with a handwheel 4 fixed to the plug 6 with a union nut 5. A lower combined seal 10 is provided between the lower end of the plug 6 and the valve body 1. An upper combined seal 9 is provided between the upper end of the plug 6 and the valve cover 3. On the plug 6, on both sides of the axis of the through hole of the plug 6, there are provided 2 semi-cylindrical sealing surfaces 12 that are parallel to the axis of the plug 6, rotate radially around the axis of the plug 6, and are formed by the gradually increasing or decreasing rotation radius, as Figure 3 shown, the point O is the central axis of the plug 6. C, B, A and C’, B’, A’ respectively rotate 180 degrees clockwise around the point O in the radial direction, and 2 semi-cylindrical sealing surfaces 12 are formed by the gradually increasing rotation radius. The rotation radii O, C < O, B < O, A; O, C’ < O, B’ < O, A’ make the rotation radius gradually increase, which helps the 2 semi-cylindrical sealing surfaces 12 to fit and tighten with the sealing surface 11 of the left plug and the sealing surface 13 of the right plug, achieving a better sealing effect. On the left plug 2 and the right plug 8, on the inner sides of the left plug 2 and the right plug 8, there are provided a sealing surface 11 of the left plug and a sealing surface 13 of the right plug corresponding to the semi-cylindrical sealing surface 12 of the plug 6, as Figure 6 , Figure 7The point O shown is the central axis D, E of the cock 6, and D', E' respectively enclose two semi-cylindrical sealing surfaces 12 corresponding to the cock 6 and radially rotate counterclockwise around the point O, forming the left cockscomb sealing surface 11 and the right cockscomb sealing surface 13. The rotation radii O, D > O, E; O, D' > O, E' make the rotation radius gradually decrease, which helps the semi-cylindrical sealing surface 12 to fit and tighten with the left cockscomb sealing surface 11 and the right cockscomb sealing surface 13, achieving a better sealing effect. The semi-cylindrical sealing surface 12 on the above-mentioned cock 6 is parallel to the axis of the cock 6 or not parallel to the axis of the cock 6. The angle of the semi-cylindrical sealing surface 12 on the above-mentioned cock 6 rotating radially around the axis of the cock 6 is 180 degrees, or greater than 180 degrees, or less than 180 degrees. The above-mentioned cock 6 is provided with a semi-cylindrical sealing surface, or a cylindrical sealing surface, that is, a cylindrical sealing surface formed by radially rotating 360 degrees with the rotation radius gradually increasing or decreasing. The two semi-cylindrical sealing surfaces 12 on the above-mentioned cock 6 are formed by radially rotating around the axis of the cock 6 with the rotation radius gradually increasing or decreasing, or are two semi-cylindrical sealing surfaces radially offset with the axis of the cock 6 as the center. The two semi-cylindrical sealing surfaces 12 formed by radially rotating around the axis of the cock 6 with the rotation radius gradually increasing or decreasing rotate in the clockwise direction or in the counterclockwise direction.

[0026] When opening the cock valve, turn the handwheel 4 clockwise to drive the cock 6 to rotate. During the rotation, since the rotation radius of the cock 6 will gradually become smaller, the semi-cylindrical sealing surface 12 on the cock 6 will rotate away from the left cockscomb sealing surface 11 and the right cockscomb sealing surface 13, making the through hole on the cock 6 correspond to the flow passage hole of the valve body 1 to open the valve, as Figure 9 shown. After the valve is opened, the left cockscomb sealing surface 11 and the right cockscomb sealing surface 13 are not in contact with the semi-cylindrical sealing surface 12. Therefore, when the valve is opened, the semi-cylindrical sealing surface 12 is not easily worn against the left cockscomb sealing surface 11 and the right cockscomb sealing surface 13 during the rotation of the cock.

[0027] When closing the cock valve, turn the handwheel 4 counterclockwise to drive the cock 6 to rotate. During the rotation, since the rotation radius of the cock 6 will gradually increase, the semi-cylindrical sealing surface 12 on the cock 6 will fit with the left cockscomb sealing surface 11 and the right cockscomb sealing surface 13 to close the valve, as Figure 11 shown. After the valve is closed, the left cockscomb sealing surface 11 and the right cockscomb sealing surface 13 fit with the semi-cylindrical sealing surface 12, and will fit tighter and tighter with the rotation of the cock 6 to achieve an ideal sealing effect.

Claims

1. A screw - type plug valve, comprising a valve body, a plug, a left packing piece, a right packing piece, a valve cover, a sealing ring, a handwheel, a union nut, an upper combined seal, a lower combined seal. A plug with a through - hole is arranged inside the valve body. Between the left and right sides of the plug and the valve body, there are a left packing piece and a right packing piece with through - holes. The axes of the through - holes of the left packing piece and the right packing piece coincide with the axis of the flow - passage hole of the valve body. At the upper end of the plug, there is a valve cover fixed to the valve body. A sealing ring is arranged between the valve cover and the valve body. At the upper end of the valve cover, there is a handwheel fixed to the plug with a union nut. Between the lower end of the plug and the valve body, there is a lower combined seal. Between the upper end of the plug and the valve cover, there is an upper combined seal; It is characterized in that: On the cock, on both sides of the axis of the cock through-hole, there are provided two semi-cylindrical sealing surfaces that are parallel to the axis of the cock, rotate radially around the axis of the cock, and are formed by gradually increasing or decreasing the rotation radius. On the left cock segment and the right cock segment, on the inner sides of the left cock segment and the right cock segment, there are provided a left cock segment sealing surface and a right cock segment sealing surface corresponding to the semi-cylindrical sealing surface of the cock.

2. The turn-tight type cock valve according to claim 1, characterized in that: The semi-cylindrical sealing surface on the above-mentioned cock is parallel to the axis of the cock or not parallel to the axis of the cock.

3. A screwing type cock valve according to claim 1 or 2, characterized in that: The angle by which the semi-cylindrical sealing surface on the above-mentioned cock rotates radially around the axis of the cock is 180 degrees, or greater than 180 degrees, or less than 180 degrees.

4. A screwing type plug valve according to claim 1, 2 or 3, characterized in that: The above-mentioned cock is provided with two semi-cylindrical sealing surfaces or a cylindrical sealing surface.

5. A tightening type plug valve according to claim 1, 2, 3 or 4, characterized in that: The two semi-cylindrical sealing surfaces on the above-mentioned cock are formed by rotating radially around the axis of the cock with the rotation radius gradually increasing or decreasing, or are two semi-cylindrical sealing surfaces formed by being radially offset with the axis of the cock as the center.

6. A screwing type plug valve according to claim 1, 2, 3 or 4, characterized in that: The two semi-cylindrical sealing surfaces that rotate radially around the axis of the cock and are formed by gradually increasing or decreasing the rotation radius rotate in the clockwise direction or in the counterclockwise direction.

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