Valve rod sealing structure of fixed ball valve

Abstract

The utility model provides a valve rod sealing structure of a fixed ball valve, and relates to the technical field of ball valves. A gland flange is arranged at the top of the valve body, a connecting support plate is arranged at the top of the gland flange, a valve rod sequentially penetrating through the gland flange and the connecting support plate is rotatably arranged in the valve body, a packing ring is arranged at the bottom of the gland flange, and the packing ring is arranged between the valve body and the valve rod. And sealing pieces are arranged between the packing ring and the valve body as well as between the gland flange and the valve rod. According to the utility model, the independent packing ring is arranged to improve the corrosion resistance and avoid the gradual increase of the switching torque and the sealing leakage after being used for a period of time.

Description

Technical Field

[0001] The utility model relates to the technical field of ball valves, in particular to a fixed ball valve stem sealing structure. Background Art

[0002] The trunnion ball valve is a new generation of high-performance ball valve, suitable for long-distance pipelines and general industrial pipelines. Its strength, safety, and resistance to harsh environments are specially considered in the design, and it is suitable for various corrosive and non-corrosive media. Usually, the gland flange is an integrated design, which not only ensures the sealing of the valve stem but also meets the anti-blowout design requirements of the valve stem.

[0003] In the prior art, the diversification of working media leads to the increased corrosion of the integral gland flange, and the rust becomes more and more serious. After a period of use, the switching torque of the existing valve gradually increases, the seal leaks, and the service life of the valve is shortened. Utility Model Content

[0004] The utility model aims to develop a fixed ball valve stem sealing structure which is provided with an independent packing ring to improve corrosion resistance and avoid the gradual increase of the switching torque and the sealing leakage after being used for a period of time.

[0005] The utility model is achieved through the following technical solutions:

[0006] A fixed ball valve stem sealing structure, comprising:

[0007] Valve body;

[0008] Gland flange, located on the top of the valve body;

[0009] Connecting support plate, arranged on the top of gland flange;

[0010] The valve stem is rotatably arranged in the valve body and passes through the gland flange and the connecting support plate in sequence;

[0011] Wherein, a packing ring is provided at the bottom of the gland flange, and the packing ring is provided between the valve body and the valve stem. Seals are provided between the packing ring and the valve body, the gland flange and the valve stem.

[0012] Optionally, a pin is provided between the valve body, the gland flange and the connecting support plate. The pin is inserted downward from the top of the connecting support plate and passes through the connecting support plate, the gland flange and the valve body in sequence. The pin is parallel to the valve stem.

[0013] Optionally, a first hexagon socket screw is threadedly connected between the gland flange and the valve body, a second hexagon socket screw is threadedly connected between the connecting support plate, the gland flange and the valve body, and the first hexagon socket screw and the second hexagon socket screw are arranged parallel to the valve stem.

[0014] Optionally, the seal between the packing ring and the valve stem includes two first installation grooves provided on the inner wall of the packing ring, and a first O-ring matching the valve stem is provided in the first installation groove.

[0015] Optionally, a first groove for the gland flange to be inserted into is provided at the top of the valve body outside the valve stem, a second groove is provided at the top of the gland flange outside the valve stem, a clamping ring matching the second groove is provided at a corresponding position on the inner edge of the bottom of the connecting support plate, and the valve stem at the bottom of the packing ring is an expanded diameter section, and the outer diameter of the expanded diameter section of the valve stem is larger than the outer diameter of the valve stem inside the packing ring.

[0016] Optionally, a sliding bearing is provided between the connecting support plate and the valve stem, a sealing gasket is provided between the second clamping groove and the clamping ring, and a thrust bearing is provided between the bottom of the packing ring and the top of the expanded diameter section of the valve stem.

[0017] Optionally, a protruding shoulder ring is provided on the outer wall of the packing ring, and the shoulder ring is located between the bottom surface of the first groove of the valve body and the bottom surface of the gland flange.

[0018] Optionally, the seal between the packing ring and the valve body includes a second installation groove arranged on the outer wall of the packing ring at the bottom of the shoulder ring, a second O-ring matching the valve body is arranged in the second installation groove, and a metal winding gasket matching the first slot of the valve body is arranged on the bottom surface of the shoulder ring.

[0019] Optionally, the sealing element between the packing ring and the gland flange comprises a metal wound gasket which is arranged on the top surface of the shoulder ring and cooperates with the bottom surface of the gland flange.

[0020] Optionally, an electrostatic spring assembly cooperating with the valve body is provided on the valve stem at the lower part of the packing ring, and the electrostatic spring assembly includes a through hole provided on the outer wall of the valve stem, an electrostatic ball is slidably provided in the through hole, and a spring is provided between the electrostatic ball and the inner end of the through hole.

[0021] The beneficial effects of the utility model are:

[0022] The utility model provides metal winding pads on the upper and lower surfaces of the shoulder ring of the packing ring, which not only improves the sealing between the valve body and the packing ring and the packing ring and the gland flange, but also has a fireproof function. The setting of the sealing pad between the gland flange and the connecting support plate not only plays a sealing role but also has a fireproof function.

[0023] The pin passes through the connecting support plate, gland flange and valve body to fix the three as a whole, reducing the risk of deflection during operation and improving the stability of the valve switch position. The valve stem is not only easy to install but also meets the requirements of anti-blowout of the valve stem.

[0024] The setting of the sliding bearing in the connecting support plate not only avoids direct contact between the valve stem and the metal, improves the centering of the valve stem, but also reduces friction, transmits torque smoothly, improves the flexibility of the valve stem rotation, and extends the service life of the valve;

[0025] The packing ring is independently set, with reliable sealing performance, effectively reducing the increase in torque caused by corrosion and rust, good sealing effect, flexible and light rotation, and the integral positioning design ensures the accuracy of the valve switch position;

[0026] The static electricity spring assembly can transfer the static electricity generated by the rotational friction between the valve seat seal ring and the ball of the fixed ball valve to the valve body through the valve stem, and then transfer the static electricity to the ground through the connection between the valve body and the pipeline, so as to avoid fire caused by static electricity. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0028] Figure 1 This is a schematic diagram of the structure of the utility model Figure 1 ;

[0029] Figure 2 is a schematic diagram of the packing ring structure;

[0030] Figure 3 This is a schematic diagram of the structure of the utility model Figure 2 ;

[0031] Figure 4 for Figure 3 Enlarged view of point A in the middle.

[0032] Figure numerals: 1. valve body; 2. packing ring; 21. first mounting groove; 22. second mounting groove; 23. shoulder ring; 3. gland flange; 4. connecting support plate; 5. valve stem; 6. first hexagon socket screw; 7. second hexagon socket screw; 8. pin; 9. electrostatic spring assembly; 91. through hole; 92. spring; 93. electrostatic ball; 10. thrust bearing; 11. sliding bearing; 12. first O-ring; 13. second O-ring; 14. metal winding gasket; 15. sealing gasket; 16. first retaining groove; 17. retaining ring; 18. second retaining groove. DETAILED DESCRIPTION

[0033] In the following, only some exemplary embodiments are briefly described. As those skilled in the art will appreciate, the described embodiments may be modified in various ways without departing from the spirit or scope of the invention. Therefore, the drawings and descriptions are considered to be exemplary and non-restrictive in nature.

[0034] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation to the present invention.

[0035] The embodiments of the present utility model are described in detail below with reference to the accompanying drawings.

[0036] like Figures 1 to 4 As shown, the utility model discloses a fixed ball valve stem sealing structure, including a valve body 1 and a valve stem 5, a gland flange 3 and a connecting support plate 4 are sequentially arranged above the valve body 1, and the valve stem 5 is rotatably connected to the valve body 1, the gland flange 3 and the connecting support plate 4.

[0037] A first groove 16 for the gland flange 3 to be inserted is provided at the top of the valve body 1 outside the valve stem 5, a second groove 18 is provided at the top of the gland flange 3 outside the valve stem 5, and a snap ring 17 matching the second groove 18 is provided at a corresponding position of the inner edge of the bottom of the connecting support plate 4. A sliding bearing 11 is provided between the connecting support plate 4 and the valve stem 5, and a sealing gasket 15 is provided between the second groove 18 and the snap ring 17.

[0038] A first hexagon socket screw 6 is threadedly connected between the gland flange 3 and the valve body 1 to achieve a detachable connection between the gland flange 3 and the valve body 1. A second hexagon socket screw 7 is threadedly connected between the connecting support plate 4, the gland flange 3 and the valve body 1 to achieve a detachable connection between the connecting support plate 4, the gland flange 3 and the valve body 1. A pin 8 is also provided between the valve body 1, the gland flange 3 and the connecting support plate 4 to connect them as a whole. The pin 8 is inserted downward from the top of the connecting support plate 4 and passes through the connecting support plate 4, the gland flange 3 and the valve body 1 in sequence. The first hexagon socket screw 6, the second hexagon socket screw 7 and the pin 8 are all arranged parallel to the valve stem 5.

[0039] A packing ring 2 is provided at the bottom of the gland flange 3. The packing ring 2 is provided between the valve body 1 and the valve stem 5. The inner wall of the packing ring 2 contacts the valve stem 5. Part of the outer wall of the packing ring 2 contacts the valve body 1. Part of the outer wall and the top of the packing ring 2 contact the gland flange 3. The valve stem 5 at the bottom of the packing ring 2 is an expanded diameter section. The outer diameter of the expanded diameter section of the valve stem 5 is greater than the outer diameter of the valve stem 5 inside the packing ring 2.

[0040] A thrust bearing 10 is provided between the bottom of the packing ring 2 and the top of the expanded diameter section of the valve stem 5. Two first mounting grooves 21 arranged up and down are provided on the inner wall of the packing ring 2. The first O-ring 12 matching the valve stem 5 is provided in both first mounting grooves 21. A second mounting groove 22 is provided on the outer wall of the packing ring 2 between the two first mounting grooves 21. The second O-ring 13 matching the valve body 1 is provided in the second mounting groove 22. A protruding shoulder ring 23 is provided on the outer wall of the packing ring 2 above the second mounting groove 22. The shoulder ring 23 is located between the bottom surface of the first groove 16 of the valve body 1 and the bottom surface of the gland flange 3. The top surface and bottom surface of the shoulder ring 23 are respectively provided with a metal winding gasket 14 matching the bottom surface of the gland flange 3 and the first groove 16 of the valve body 1.

[0041] An electrostatic spring assembly 9 cooperating with the valve body 1 is provided on the expanded diameter section of the valve stem 5. The electrostatic spring assembly 9 can transfer the static electricity generated by the rotational friction between the sealing ring of the fixed ball valve seat and the ball through the valve stem 5 to the valve body 1, and the valve body 1 is connected to the pipeline and transferred to the ground to avoid fire caused by static electricity.

[0042] The electrostatic spring assembly 9 includes a through hole 91 provided on the outer wall of the expanded diameter section of the valve stem 5. The through hole 91 is horizontally arranged. An electrostatic ball 93 is slidably provided in the through hole 91. A spring 92 is provided between the electrostatic ball 93 and the inner end of the through hole 91. The elastic force of the spring 92 causes the electrostatic ball 93 to slide toward the outside of the through hole 91 and keeps the electrostatic ball 93 in contact with the valve body 1 outside the through hole 91.

[0043] The shoulder ring 23 of the packing ring 2 of the utility model is provided with metal winding gaskets 14 on both the upper and lower surfaces, which not only improves the sealing between the valve body 1 and the packing ring 2 and the packing ring 2 and the gland flange 3, but also has a fireproof function. The setting of the sealing gasket 15 between the gland flange 3 and the connecting support plate 4 not only plays a sealing role but also has a fireproof function.

[0044] The pin shaft 8 passes through the connecting support plate 4, the gland flange 3, and the valve body 1 to fix the three as a whole, which reduces the risk of deflection during operation and improves the stability of the valve switch position. The valve stem 5 is not only easy to install but also meets the requirements of anti-blowout of the valve stem 5;

[0045] The arrangement of the sliding bearing 11 in the connecting support plate 4 not only avoids direct contact between the valve stem 5 and metal, and improves the centering of the valve stem 5, but also reduces friction, ensures stable transmission torque, improves the flexibility of the valve stem 5 rotation, and prolongs the service life of the valve;

[0046] The packing ring 2 is independently set, with reliable sealing performance, effectively reducing the increase in torque caused by corrosion and rust, good sealing effect, flexible and light rotation, and the integral positioning design ensures the accuracy of the valve switch position;

[0047] The static electricity spring assembly 9 can transfer the static electricity generated by the friction between the fixed ball valve seat seal ring and the ball through the valve stem 5 to the valve body 1, and the valve body 1 is connected to the pipeline and transferred to the ground, so as to avoid fire caused by static electricity.

[0048] The above embodiments are only preferred embodiments of the present utility model and are not limitations on the technical solutions of the present utility model. Any technical solution that can be implemented on the basis of the above embodiments without creative work should be deemed to fall within the scope of protection of the patent of the present utility model.

Claims

1. A fixed ball valve stem sealing structure, It is characterized in that include: Valve body; Gland flange, located on the top of the valve body; Connecting support plate, arranged on the top of gland flange; The valve stem is rotatably arranged in the valve body and passes through the gland flange and the connecting support plate in sequence; Wherein, a packing ring is provided at the bottom of the gland flange, and the packing ring is provided between the valve body and the valve stem. Seals are provided between the packing ring and the valve body, the gland flange and the valve stem.

2. The stem sealing structure of a trunnion-mounted ball valve according to claim 1, It is characterized in that A pin is provided between the valve body, the gland flange and the connecting support plate. The pin is inserted downward from the top of the connecting support plate and passes through the connecting support plate, the gland flange and the valve body in sequence. The pin is parallel to the valve stem.

3. The stem sealing structure of a trunnion-mounted ball valve according to claim 1, It is characterized in that A first hexagon socket screw is threadedly connected between the gland flange and the valve body, and a second hexagon socket screw is threadedly connected between the connecting support plate, the gland flange and the valve body. The first hexagon socket screw and the second hexagon socket screw are arranged parallel to the valve stem.

4. The stem sealing structure of a trunnion-mounted ball valve according to claim 1, It is characterized in that The sealing element between the packing ring and the valve stem comprises two first installation grooves arranged on the inner wall of the packing ring, and a first O-ring matched with the valve stem is arranged in the first installation groove.

5. The stem sealing structure of a trunnion-mounted ball valve according to claim 1, It is characterized in that A first groove for the gland flange to be inserted into is provided at the top of the valve body outside the valve stem, and a second groove is provided at the top of the gland flange outside the valve stem. A clamping ring matching the second groove is provided at a corresponding position on the inner edge of the bottom of the connecting support plate. The valve stem at the bottom of the packing ring is an expanded diameter section, and the outer diameter of the expanded diameter section of the valve stem is larger than the outer diameter of the valve stem inside the packing ring.

6. The stem sealing structure of a trunnion-mounted ball valve according to claim 5, It is characterized in that A sliding bearing is arranged between the connecting support plate and the valve stem, a sealing gasket is arranged between the second clamping groove and the clamping ring, and a thrust bearing is arranged between the bottom of the packing ring and the top of the valve stem expansion section.

7. The stem sealing structure of a trunnion-mounted ball valve according to claim 5, It is characterized in that A protruding shoulder ring is provided on the outer wall of the packing ring, and the shoulder ring is located between the bottom surface of the first clamping groove of the valve body and the bottom surface of the gland flange.

8. The stem sealing structure of a trunnion-mounted ball valve according to claim 7, It is characterized in that The seal between the packing ring and the valve body includes a second installation groove arranged on the outer wall of the packing ring at the lower part of the shoulder ring, a second O-ring matching the valve body is arranged in the second installation groove, and a metal winding gasket matching the first groove of the valve body is arranged on the bottom surface of the shoulder ring.

9. The stem sealing structure of a trunnion-mounted ball valve according to claim 7, It is characterized in that The sealing element between the packing ring and the gland flange comprises a metal winding gasket which is arranged on the top surface of the shoulder ring and matches with the bottom surface of the gland flange.

10. The stem sealing structure of a trunnion-mounted ball valve according to any one of claims 1 to 9, It is characterized in that An electrostatic spring assembly cooperating with the valve body is provided on the valve stem at the lower part of the packing ring. The electrostatic spring assembly includes a through hole provided on the outer wall of the valve stem. An electrostatic ball is slidably provided in the through hole. A spring is provided between the electrostatic ball and the inner end of the through hole.

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