Track ball valve

Abstract

The invention discloses a track ball valve which is small in valve seat structure limitation and convenient to disassemble, further reduces a gap between a ball body and a valve seat during sealing, and is good in sealing effect. The ball valve comprises a valve body, an axial flow channel is formed in the valve body, a ball body is arranged in the middle of the axial flow channel, and a valve seat sealing structure is arranged on one side of the ball body and on the axial flow channel, and is characterized in that the valve seat sealing structure comprises a valve seat, a graphite ring and an inner hexagonal flat end set screw, the valve seat is annular and is arranged in a multi-layer sealing mode, and the graphite ring is arranged on the valve seat. A valve seat sealing face can be bent to be attached to a ball body sealing face, the valve seat is installed on the valve body through a hexagon socket set screw with a flat end, the hexagon socket set screw with the flat end does not completely limit the valve seat, displacement allowance exists in the valve seat during sealing, and a graphite ring is installed in a gap between the valve seat and the valve body.

Description

Technical Field

[0001] The invention relates to the technical field of ball valve devices, and in particular to a track ball valve. Background Art

[0002] Track ball valve is a relatively new type of ball valve. According to different structural forms, track ball valve can be divided into floating ball valve, fixed ball valve and elastic ball valve. Its working principle is that when the valve is in the fully open position, the valve stem starts to drop and drives the ball to start rotating. When the valve is about to close, the valve stem drives the ball to rotate ninety degrees without friction with the valve seat sealing surface. Then the valve stem continues to drop, mechanically presses the ball to press it tightly on the valve seat to achieve complete sealing. On the contrary, when the valve is in the fully closed position, the valve stem rises and drives the ball to rotate, so that the valve is opened. Then the existing track ball valve seat structure is restricted and inconvenient to disassemble. When the ball contacts and seals with the valve seat, the gap between the ball and the valve seat is still large, and the sealing effect cannot be guaranteed. Summary of the invention

[0003] In view of the shortcomings of the existing track ball valve ball seat structure being restricted and inconvenient to disassemble, and the gap between the ball and the valve seat being large after the ball is in contact and sealed, and the sealing effect cannot be guaranteed, the present invention provides a track ball valve, whose valve seat structure has fewer restrictions and is easy to disassemble, which further reduces the gap between the ball and the valve seat during sealing and has a better sealing effect.

[0004] The present invention provides the following technical solutions: A track ball valve, comprising a valve body, an axial flow channel is provided inside the valve body, a ball is arranged in the middle of the axial flow channel, and a valve seat sealing structure is provided on one side of the ball in the axial flow channel, characterized in that: the valve seat sealing structure comprises a valve seat, a graphite ring and a hexagon socket flat-end set screw, the valve seat is annular and has a multi-layer sealing arrangement, the valve seat sealing surface can be bent and fits the ball sealing surface, the valve seat is installed on the valve body by a hexagon socket flat-end set screw, the hexagon socket flat-end set screw does not completely define the valve seat, and the valve seat exists when sealing. Displacement allowance, a graphite ring is installed in the gap between the valve seat and the valve body, a connecting bracket is installed on the top of the upper valve cover, the valve stem in the connecting bracket passes through the upper valve cover and the valve body in sequence and is inserted into the ball, a guide groove is opened in the middle part of the valve stem, and the connecting bracket is installed with a guide groove for inserting a support pin into the valve stem, an upper bearing matching the valve stem is provided in the upper valve cover, the lower end of the ball is inserted into the bottom of the valve body, and a lower bearing matching the ball is provided at the bottom of the valve body, and a valve core pin is installed in parallel at the connection between the valve stem and the ball, and the valve core pin has a guiding function.

[0005] It is further characterized by: A sewage discharge channel is provided at the bottom of the valve body, a bottom cover is provided at the opening of the sewage discharge channel, and the bottom cover is connected to the valve body by bolts; The connection positions between the connecting bracket and the upper valve cover as well as between the upper valve cover and the valve body are all provided with flat keys.

[0006] In the above technical solution, the technical effects and advantages provided by the present invention are: The valve seat in the valve seat sealing structure is installed by the hexagon socket flat-end set screws in a non-completely limited manner. On the one hand, the valve seat is more convenient to disassemble and assemble. On the other hand, it ensures that the valve seat can be slightly displaced during sealing to ensure the sealing effect of the valve seat. The valve seat is set as a multi-layer sealing structure, which has a better sealing effect. At the same time, the sealing surface of the valve seat can be slightly bent to better fit the sealing surface of the ball, further enhancing the sealing performance of the valve. The graphite ring itself has good sealing performance and after the graphite ring is burned, it relies on the back side of the valve seat and the valve body to form a sealing surface, which has a fire-proof effect; Flat keys are added between the connecting bracket and the upper valve cover and between the upper valve cover and the valve body to ensure the relative position of the valve during installation, so that the ball will not be deflected when the valve stem is in the closed position, and the connecting bracket and the upper valve cover are prevented from rotating together when the torque is too large. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1 It is a schematic diagram of the overall structure of the present invention; Figure 2 It is an enlarged schematic diagram of structure A of the present invention; Figure 3 Schematic diagram of the valve seat multi-layer sealing arrangement structure.

[0008] Description of reference numerals: 1. Valve body; 2. Upper valve cover; 3. Valve seat; 4. Ball; 5. Valve stem; 6. Upper bearing; 7. Lower bearing; 8. Bottom cover; 9. Valve core pin; 10. Support pin; 11. Connecting bracket; 12. Graphite ring; 13. Hexagon socket flat end set screw; 14. Flat key. DETAILED DESCRIPTION

[0009] The present invention provides Figure 1 The track ball valve shown in the figure comprises a valve body 1, an upper valve cover 2 is inserted into the valve body 1 and fixedly connected by bolts, an axial flow channel is opened inside the valve body 1, a ball 4 is arranged in the middle of the axial flow channel, and the ball 4 is an incomplete hollow sphere. On one side of the ball 4, a valve seat sealing structure is arranged in the axial flow channel, and the valve seat sealing structure comprises a valve seat 3, a graphite ring 12 and a hexagon socket flat end set screw 13. The valve seat 3 is annular and has a multi-layer sealing arrangement, which includes a graphite layer (see Figure 3), the sealing effect is better and the sealing surface of the valve seat 3 can be slightly bent and better fit the sealing surface of the ball 4. The valve seat 3 is installed on the valve body 1 by the hexagon socket flat end set screw 13. The hexagon socket flat end set screw 13 does not completely limit the valve seat 3. The valve seat 3 can be slightly displaced during sealing, further improving the sealing performance. A graphite ring 12 is installed in the gap between the valve seat 3 and the valve body 1. The graphite ring 12 has good sealing and corrosion resistance. When the graphite ring 12 is burned, it relies on the back side of the valve seat 3 and the valve body 1 to form a sealing surface and has a fireproof effect; A connecting bracket 11 is installed on the top of the upper valve cover 2. The valve stem 5 in the connecting bracket 11 passes through the upper valve cover 2 and the valve body 1 in sequence and then is inserted into the ball 4. A guide groove is provided in the middle part of the valve stem 5. The connecting bracket 11 is installed with a support pin 10 to insert into the guide groove of the valve stem 5. An upper bearing 6 matching the valve stem 5 is provided in the upper valve cover 2. The lower end of the ball 4 is inserted into the bottom of the valve body 1. A lower bearing 7 matching the ball 4 is provided at the bottom of the valve body 1. A valve core pin 9 is installed in parallel at the connection between the valve stem 5 and the ball 4, and the valve core pin 9 has a guiding function; A sewage discharge channel is provided at the bottom of the valve body 1, and a bottom cover 8 is provided at the opening of the sewage discharge channel. The bottom cover 8 is connected to the valve body 1 by bolts. Flat keys 14 are provided at the connection points between the connecting bracket 11 and the upper valve cover 2 as well as between the upper valve cover 2 and the valve body 1. The flat keys 14 ensure the relative position of the valve during installation.

[0010] Working principle of the present invention: When the valve needs to be closed, the valve stem 5 begins to descend and causes the ball 4 to leave the valve seat 3 and begin to rotate. The valve stem 5 continues to descend and is acted upon by the support pin, causing the valve stem 5 and the ball 4 to rotate 90° at the same time. When the valve is about to be closed, the ball 4 has rotated 90° without contact with the valve seat 3. The valve stem 5 continues to descend and mechanically wedges the ball 4, causing it to press tightly against the valve seat 3 to complete the seal. During the process of the ball 4 pressing down, there is a slight compression between the valve seat 3 and the graphite ring 12, which enhances the sealing performance of the valve seat 3.

Claims

1. A track ball valve, comprising a valve body, an axial flow channel is provided inside the valve body, a ball is provided in the middle of the axial flow channel, and a valve seat sealing structure is provided on one side of the ball, characterized in that: The valve seat sealing structure comprises a valve seat, a graphite ring and a hexagon socket flat end set screw. The valve seat is annular and has a multi-layer sealing arrangement. The valve seat sealing surface can be bent and fits the ball sealing surface. The valve seat is installed on the valve body by the hexagon socket flat end set screw. The hexagon socket flat end set screw does not completely limit the valve seat. There is a displacement margin for the valve seat during sealing. A graphite ring is installed in the gap between the valve seat and the valve body. A connecting bracket is installed on the top of the upper valve cover. The valve stem in the connecting bracket passes through the upper valve cover and the valve body in sequence and then inserts into the ball. A guide groove is opened in the middle part of the valve stem. The connecting bracket is installed with a guide groove for supporting a pin to insert into the valve stem. An upper bearing matching the valve stem is provided in the upper valve cover. The lower end of the ball is inserted into the bottom of the valve body. A lower bearing matching the ball is provided at the bottom of the valve body. Valve core pins are installed in parallel at the connection between the valve stem and the ball. The valve core pin has a guiding function.

2. A track ball valve according to claim 1, characterized in that: A sewage discharge channel is provided at the bottom of the valve body, a bottom cover is provided at the opening of the sewage discharge channel, and the bottom cover is connected to the valve body by bolts.

3. A track ball valve according to claim 1 or 2, characterized in that: The connection positions between the connecting bracket and the upper valve cover as well as between the upper valve cover and the valve body are all provided with flat keys.

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