Stop valve

Abstract

The utility model relates to the technical field of valves, and particularly discloses a stop valve which comprises a valve body, a valve cover, a valve rod part, a gland assembly and a packing assembly, the valve cover is arranged on the valve body, one end of the valve rod part penetrates through the valve cover and then extends into the valve body, a packing groove is formed between the valve cover and a valve rod, and the packing assembly is tightly pressed in the packing groove through the gland assembly. The gland assembly comprises a cover body and a pressing plate, the cover body is formed by sequentially splicing a plurality of pressing blocks, the two ends of the cover body abut against the filler assembly and the pressing plate respectively, the pressing plate is detachably installed on the valve body, a sealing piece located in the valve body is arranged on the valve rod part, the valve rod part can slide relative to the valve body, and the moving track of the sealing piece passes through the opening limit position. When the sealing piece is located at the opening limit position, the sealing piece abuts against the valve deck. The stop valve disclosed by the utility model has the function of replacing the filler on line.

Description

Technical Field

[0001] This utility model belongs to the field of valve technology, specifically a gate valve. Background Technology

[0002] Gate valves are mainly used to cut off or regulate the flow of fluid. For example... Figure 1 As shown, the existing gate valve includes a valve body 1', a valve stem 2', a packing assembly 3', a packing gland 4', a bracket 5', and a guide plate 6'. The bracket 5' is threadedly connected to the valve body 1'. The valve stem 2' extends into the valve body 1'. The packing assembly 3' is disposed between the valve stem 2' and the valve body 1'. The packing gland 4' presses the packing assembly 3' into the valve body 1' and is mounted on the bracket 5' by a hinge bolt. The guide plate 6' is mounted on the valve stem 2', and the bracket 5' is provided with a slide rail that mates with the guide plate 6'.

[0003] Because the seal between the valve body and the valve stem mainly relies on packing seal, when the packing is replaced, the valve body and valve stem cannot be sealed, thus making it impossible to replace the packing online. Therefore, there is an urgent need to design a gate valve to solve the above problems. Utility Model Content

[0004] The purpose of this invention is to provide a shut-off valve that enables online packing replacement.

[0005] To solve the above-mentioned technical problems, this utility model provides a gate valve, including a valve body, a valve cover, a valve stem, a gland assembly, and a packing assembly. The valve cover is disposed on the valve body, and one end of the valve stem extends through the valve cover into the valve body. A packing groove is formed between the valve cover and the valve stem. The gland assembly presses the packing assembly into the packing groove. The gland assembly includes a cover body and a pressure plate. The cover body is a ring structure formed by multiple pressure blocks sequentially spliced ​​and abutting. The pressure plate is detachably installed on the valve body and cooperates with the cover body to press the cover body onto the packing assembly. A sealing element is provided on the valve stem, located inside the valve body. The valve stem can slide relative to the valve body, and the movement trajectory of the sealing element passes through the opening limit position. When the sealing element is at the opening limit position, the sealing element abuts against the valve cover, so that the valve stem and the valve cover are sealed together.

[0006] Furthermore, at least one pressure block is a guide block that cooperates with the valve stem. The guide block has a first groove on the side facing the valve stem, and a second groove is provided on the valve stem. The valve stem cooperates with the guide block through a guide key. One of the first groove and the second groove is a guide through groove and the other is a keyway. The length direction of the guide through groove is parallel to the axial direction of the valve stem. The guide key is set in the keyway and slides in cooperation with the guide through groove.

[0007] Furthermore, the pressure plate is annular and is fitted onto the outside of the cover. The inner hole of the pressure plate has an anti-rotation section that mates with the cover. The cross-section of the anti-rotation section perpendicular to the axial direction of the valve stem is a non-circular surface.

[0008] Furthermore, the pressure plate is annular and is fitted onto the outside of the cover. The inner side of the pressure plate has a pressing surface that abuts against all the pressure blocks, and the pressing surface is inclined inward in a direction away from the packing assembly.

[0009] Furthermore, the pressure plate is annular and is sleeved on the outside of the cover. Its inner hole is a first stepped hole, which includes a first large-diameter hole and a first small-diameter hole arranged sequentially in the direction away from the packing assembly. The cover has a stepped shaft that mates with the first stepped hole.

[0010] Furthermore, a first stepped surface is formed between the first large-diameter hole and the first small-diameter hole. The first stepped surface is inclined inward in a direction away from the packing assembly, and the stepped shaft has a second stepped surface that mates with the first stepped surface.

[0011] Furthermore, the valve cover has a valve cover hole through which the valve stem passes, and the inner peripheral wall of the valve cover has a sealing surface on the end facing the seal, the sealing surface gradually tilting outward in the direction towards the seal, and the seal has a mating surface that seals with the sealing surface.

[0012] Furthermore, a sealing gasket is provided between the valve body and the valve cover.

[0013] Furthermore, it also includes a bracket installed on the valve body, which presses the valve cover tightly against the valve body, and an adjustment shim is provided between the bracket and the valve cover.

[0014] Furthermore, the bracket has a first threaded hole that is threaded to the valve body, and a threaded anti-loosening part is provided between the bracket and the valve body. The threaded anti-loosening part includes a first through hole, a second blind hole, and an anti-loosening bolt. The first through hole is formed on the bracket, and the second blind hole is formed on the valve body and is correspondingly provided to the first through hole. One of the first through hole and the second blind hole is a second threaded hole, and the other hole is a mating hole. The anti-loosening bolt is threaded to the second threaded hole and is partially located in the mating hole.

[0015] The beneficial effects of this utility model are as follows: By installing a valve cover inside the valve body, with the valve cover and valve body in a sealed fit, and a sealing fit structure between the valve stem and valve cover, when the packing needs to be replaced, simply raise the valve stem to the first position. At this time, the valve stem and valve cover are in a sealed fit, thus enabling the packing replacement. Simultaneously, by setting the gland assembly as a split structure, quick disassembly and assembly of the gland assembly can be achieved, thereby improving the packing replacement efficiency.

[0016] By installing a guide key between the valve stem and the cover, the existing guide plate design is replaced, reducing the overall height of the valve and making the valve design more compact.

[0017] When the valve stem rises to the opening limit position, the valve cover and valve stem seal together, preventing the medium from entering the valve cover and eroding the packing, thereby extending the service life of the packing. Attached Figure Description

[0018] To more clearly illustrate the technical solution of this utility model, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a cross-sectional view of a shut-off valve in the prior art;

[0020] Figure 2 This is a cross-sectional view of the shut-off valve in Embodiment 1 of this utility model;

[0021] Figure 3 This is a cross-sectional view of the valve cover in Embodiment 1 of this utility model;

[0022] Figure 4 This is a front view of the valve stem portion in Embodiment 1 of this utility model;

[0023] Figure 5 The valve stem portion of Embodiment 1 of this utility model is along Figure 4 A cross-sectional view along line AA;

[0024] Figure 6 This is a cross-sectional view of the pressure plate in Embodiment 1 of this utility model;

[0025] Figure 7 This is a top view of the pressure plate in Embodiment 1 of this utility model;

[0026] Figure 8 This is a cross-sectional view of the cover body in Embodiment 1 of this utility model;

[0027] Figure 9 This is a top view of the cover body of Embodiment 1 of this utility model; and

[0028] Figure 10 This is a cross-sectional view of the shut-off valve in Embodiment 2 of this utility model.

[0029] In the diagram: 1' is the valve body, 2' is the valve stem, 3' is the packing assembly, 4' is the packing gland, 5' is the bracket, 6' is the guide plate, 1 is the valve body, 11 is the valve cavity, 12 is the third step surface, 2 is the valve cover, 21 is the upper step surface, 22 is the lower step surface, 23 is the through hole, 24 is the sealing surface, 3 is the bracket, 31 is the connecting ring, 32 is the anti-loosening bolt, 4 is the valve stem section, 41 is the valve stem, 42 is the second groove, and 43 is the guide. Key, 44 is a sealing element, 441 is a mating surface, 5 is a gland assembly, 51 is a cover body, 511 is a pressure block, 512 is a first groove, 513 is a mating section, 514 is a second step surface, 52 is a pressure plate, 521 is a first step hole, 522 is a first step surface, 523 is an anti-rotation section, 524 is a pressing surface, 53 is a packing clamping bolt, 54 is a packing clamping nut, 6 is a packing assembly, 7 is a sealing gasket, and 8 is an adjusting shim. Detailed Implementation

[0030] The technical solutions in the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0031] Example 1

[0032] The following will describe a specific embodiment of this utility model and its appendix. Figure 2-6 Let me explain in detail.

[0033] Figure 2 This is a cross-sectional view of the shut-off valve in Embodiment 1 of this utility model; Figure 3 This is a cross-sectional view of the valve cover in Embodiment 1 of this utility model; Figure 4 This is a front view of the valve stem portion in Embodiment 1 of this utility model; Figure 5 The valve stem portion of Embodiment 1 of this utility model is along Figure 4 A cross-sectional view along line AA; Figure 6 This is a cross-sectional view of the pressure plate in Embodiment 1 of this utility model; Figure 7 This is a top view of the pressure plate in Embodiment 1 of this utility model; Figure 8 This is a cross-sectional view of the cover body in Embodiment 1 of this utility model; Figure 9 This is a top view of the cover of Embodiment 1 of this utility model.

[0034] like Figure 2-9 As shown, a shut-off valve in this embodiment includes a valve body 1, a bracket 3, a valve cover 2, a valve stem 4, a gland assembly 5, and a packing assembly 6.

[0035] Valve body 1 includes a body, a valve cavity 11 formed within the body, and a valve chamber 11 formed at one end of the body (e.g., Figure 2 The third step hole (shown as the upper end of valve body 1) is connected to valve cavity 11 and has a third step surface 12.

[0036] The valve cover 2 is mounted on the valve body 1 and a sealing gasket 7 is provided between the valve cover 2 and the valve body 1. The valve cover 2 is located at the end inside the valve body 1 (e.g., Figure 2 The lower end of the valve cover 2 (shown as the outer peripheral wall) has an annular notch, thus forming a lower step surface 22 at the lower end of the valve cover 2. A sealing gasket 7 is disposed between the third step surface 12 and the lower step surface 22. The portion of the valve cover 2 located outside the valve body 1 (e.g., Figure 2 The outer peripheral wall of the valve cover 2 (shown as the upper part) is provided with a flange, thereby forming an upper stepped surface 21 on the outer side of the upper part of the valve cover 2.

[0037] One end of bracket 3 (e.g.) Figure 2 The lower end of the bracket 3 (shown as the lower part) is integrally formed with a connecting ring 31, which has a first threaded hole for threaded connection with the valve body 1. A threaded anti-loosening part is provided between the bracket 3 and the valve body 1. The threaded anti-loosening part includes a first through hole, a second blind hole, and an anti-loosening bolt 32. The first through hole is formed on the bracket 3, and the second blind hole is formed on the valve body 1 and is correspondingly arranged to the first through hole. This corresponding arrangement means that the first through hole and the second blind hole are coaxially arranged. One of the first through hole and the second blind hole is a second threaded hole, and the other hole is a mating hole. The anti-loosening bolt 32 is threadedly connected to the second threaded hole and is partially located within the mating hole. The axis of the first threaded hole and the axis of the second threaded hole are not collinear; specifically, the axial direction of the first threaded hole is perpendicular to the axial direction of the second threaded hole. The threaded anti-loosening part prevents the threaded connection between the bracket 3 and the valve body 1 from loosening due to vibration during valve operation. In this embodiment, the first through hole is a second threaded hole, and the second blind hole is a tapered mating hole with a smooth surface.

[0038] The inner wall of the connecting ring 31, away from the valve body 1, protrudes inward to form an inner flange. This inner flange secures the valve cover 2 to the valve body 1. An adjusting shim 8 is provided between the inner flange and the upper stepped surface 21. By controlling the thickness of the adjusting shim 8, the height of the bracket 3 after it is screwed tightly onto the valve body 1 is controlled.

[0039] One end of the valve stem 4 (e.g.) Figure 2The lower end of the valve stem portion 4 (shown as the lower end) passes through the valve cover 2 and extends into the valve body 1. The valve stem portion 4 includes an integrally formed valve stem 41 and a seal 44, which is located within the valve body 1. The valve stem portion 4 can slide relative to the valve body 1, and the movement trajectory of the seal 44 passes through the opening limit position. When the seal 44 is at the opening limit position, the valve opening is at its maximum, and the seal 44 abuts against the valve cover 2, so that the valve stem 41 and the valve cover 2 are sealed together. When the valve is open, the back seal can reduce the erosion of the packing by the medium, extend the service life of the packing, and also has the function of online packing replacement.

[0040] Specifically, the valve cover 2 has a valve cover hole 23 through which the valve stem 41 passes. The inner peripheral wall of the valve cover 2 has a sealing surface 24 on the end facing the seal 44, and this sealing surface 24 gradually slopes outwards in the direction towards the seal 44. The valve stem portion 4 has a mating surface 441 that seals with the sealing surface 24. In other embodiments, both the sealing surface 24 and the mating surface 441 may be planar. Furthermore, in this embodiment, a sealing material such as stainless steel or hard alloy is welded onto the inner peripheral wall of the valve cover 2 at the end away from the gland assembly 5. The surface of this sealing material facing the seal 44 forms the sealing surface 24, and the valve stem portion 4 is a one-piece structure made of stainless steel. Of course, in other embodiments, the valve cover 2 may also be directly made of stainless steel or hard alloy, with the inner peripheral wall of the valve cover 2 forming the sealing surface 24 on the surface away from the gland assembly 5, or the sealing material may be welded onto the side of the seal 44 facing the sealing surface 24. By setting the inclined sealing surface 24, compared with flat contact, the inclined setting of the sealing surface 24 can make the sealing element 44 of the valve stem 41 fit more tightly with the sealing surface 24 of the valve cover 2, thereby improving the sealing reliability.

[0041] A packing groove is formed between the valve cover 2 and the valve stem 41.

[0042] The gland assembly 5 presses the packing assembly 6 into the packing groove.

[0043] The cap assembly 5 includes an annular cap 51 and an annular pressure plate 52. The cap 51 and the pressure plate 52 are arranged sequentially in a direction away from the valve body 1 and are respectively fitted onto the outside of the valve stem portion 4.

[0044] The cover 51 is composed of multiple pressure blocks 511 that are sequentially fitted together and abutted end to end. Preferably, the cover 51 is composed of two pressure blocks 511, which are symmetrically arranged with respect to the valve stem 41. The two ends of the cover 51 abut against the packing assembly and the pressure plate 52, respectively. The cover 51 is composed of two parts of the same size, which has the function of quick installation and disassembly. The pressure plate 52 is detachably installed on the valve body 1 by means of a fastening assembly. Specifically, the fastening assembly includes a packing clamping bolt 53 and a packing clamping nut 54. The pressure plate 52 is provided with a connecting through hole, and the bracket 3 is provided with a connecting threaded hole. One end of the packing clamping bolt 53 passes through the connecting through hole and is threadedly connected to the connecting threaded hole. The other end of the packing clamping bolt 53 is threadedly connected to the packing clamping nut 54, which abuts against the pressure plate 52.

[0045] At least one pressure block 511 is a guide block that mates with the valve stem 41. A first groove 512 is provided on the side of the guide block facing the valve stem 41, and a second groove 42 is provided on the valve stem portion 4. The valve stem 41 mates with the guide block via a guide key 43. One of the first groove 512 and the second groove 42 is a guide groove, and the other is a keyway. The length direction of the guide groove is parallel to the axial direction of the valve stem 41 (e.g., ...). Figure 2 (Shown in the vertical direction), the guide key 43 is set in the keyway and slides in cooperation with the guide groove. By setting the guide key 43 between the valve stem 41 and the cover 51, the guide plate design in the prior art is replaced, reducing the overall height of the valve and making the valve design more compact. In this embodiment, the first groove 512 is a guide groove, and the second groove 42 is a keyway to ensure that the valve stem 41 has sufficient strength; both pressure blocks 511 are guide blocks and are respectively provided with keyways, and the valve stem 41 is keyed to each pressure block 511 and the valve stem 41.

[0046] The pressure plate 52 is annular and is fitted onto the outside of the cover 51. Its inner hole is a first stepped hole 521, which includes a first large-diameter hole and a first small-diameter hole arranged sequentially in a direction away from the packing assembly 6. The cover 51 has a stepped shaft that mates with the first stepped hole 521. A first stepped surface 522 is formed between the first large-diameter hole and the first small-diameter hole. The first stepped surface 522 is inclined inward in a direction away from the packing assembly 6. The stepped shaft has a second stepped surface 514 that mates with the first stepped surface 522. The first stepped surface 522 and the second stepped surface 514 mate to press all the pressure blocks 511 onto the packing assembly 6. The inclined arrangement of the stepped surfaces prevents multiple pressure blocks 511 from separating. Furthermore, the inclined arrangement of the stepped surfaces provides automatic centering, ensuring that the clamping force provided by the packing clamping bolts 53 and packing clamping nuts 54 on both sides of the pressure plate 52 is evenly transmitted to the packing assembly 6 through the cover 51, guaranteeing the reliability of the seal of the packing assembly 6.

[0047] The inner hole of the pressure plate 52 has an anti-rotation section 523, and the cover 51 has a mating section 513 that matches the shape of the anti-rotation section 523. In this embodiment, the first small-diameter hole constitutes the anti-rotation section 523. The cross-section of the anti-rotation section 523 perpendicular to the axial direction of the valve stem 41 is a non-circular surface. This non-circular surface can be an ellipse, a polygonal surface, etc., as long as it achieves the anti-rotation function of the cover 51. In this embodiment, the non-circular surface is a whole circle with a portion cut off on each of its opposite sides, and the two sides of the mating section 513 are milled flat.

[0048] Example 2

[0049] In this second embodiment, the parts that are the same as in the first embodiment are numbered the same.

[0050] Figure 10 This is a cross-sectional view of the shut-off valve in Embodiment 2 of this utility model.

[0051] like Figure 10 As shown, the difference between this embodiment 2 and embodiment 1 lies in the anti-rotation mating structure of the pressure plate 52 and the cover 51. In this embodiment, the pressure plate 52 is annular and is sleeved on the outside of the cover 51. The inner side of the pressure plate 52 has a pressing surface 524 that abuts against all the pressing blocks 511. The pressing surface 524 is inclined inward in a direction away from the packing assembly 6.

[0052] The above-disclosed embodiment is merely a preferred embodiment of the present utility model and should not be construed as limiting the scope of the present utility model. Therefore, any equivalent variations made in accordance with the claims of the present utility model shall still fall within the scope of the present utility model.

Claims

1. A shut-off valve, comprising a valve body (1), a valve cover (2), a valve stem portion (4), a gland assembly (5), and a packing assembly (6), wherein the valve cover (2) is disposed on the valve body (1), one end of the valve stem portion (4) passes through the valve cover (2) and extends into the valve body (1), a packing groove is formed between the valve cover (2) and the valve stem portion (4), and the gland assembly (5) presses the packing assembly (6) into the packing groove, characterized in that, The gland assembly (5) includes a cover (51) and a pressure plate (52). The cover (51) is a ring structure formed by splicing multiple pressure blocks (511). The pressure plate (52) is detachably installed on the valve body (1) and cooperates with the cover (51) to press the cover (51) onto the packing assembly. The valve stem (4) is provided with a sealing element (44) located inside the valve body (1). The valve stem (4) can slide relative to the valve body (1) and the movement trajectory of the sealing element (44) passes through the opening limit position. When the sealing element (44) is located at the opening limit position, the sealing element (44) abuts against the valve cover (2) so that the valve stem and the valve cover (2) are sealed together.

2. The shut-off valve according to claim 1, characterized in that, At least one of the pressure blocks (511) is a guide block that cooperates with the valve stem portion (4). The guide block has a first groove (512) on the side facing the valve stem portion, and a second groove (42) is provided on the valve stem portion (4). The valve stem cooperates with the guide block through a guide key (43). One of the first groove (512) and the second groove (42) is a guide through groove and the other groove is a keyway. The length direction of the guide through groove is parallel to the axial direction of the valve stem portion (4). The guide key (43) is located in the keyway and slides in cooperation with the guide through groove.

3. The shut-off valve according to claim 2, characterized in that, The pressure plate (52) is sleeved on the outside of the cover (51). The inner hole of the pressure plate (52) has an anti-rotation section (523) that cooperates with the cover (51). The cross section of the anti-rotation section (523) perpendicular to the axial direction of the valve stem (4) is a non-circular surface.

4. The shut-off valve according to any one of claims 1 to 3, characterized in that, The inner side of the pressure plate (52) has a pressing surface (524) that abuts against all the pressing blocks (511), and the pressing surface (524) is inclined inward in a direction away from the packing assembly (6).

5. The shut-off valve according to any one of claims 1 to 3, characterized in that, The inner hole of the pressure plate (52) is a first stepped hole (521). The first stepped hole (521) includes a first large-diameter hole and a first small-diameter hole arranged sequentially in a direction away from the packing assembly (6). The cover (51) has a stepped shaft that mates with the first stepped hole (521).

6. The shut-off valve according to claim 5, characterized in that, A first stepped surface (522) is formed between the first large-diameter hole and the first small-diameter hole. The first stepped surface (522) is inclined inward in a direction away from the packing assembly (6). The stepped shaft has a second stepped surface (514) that mates with the first stepped surface (522).

7. The shut-off valve according to claim 1, characterized in that, The valve cover (2) has a valve cover hole (23) through which the valve stem passes. The inner peripheral wall of the valve cover (2) is provided with a sealing surface (24) at one end facing the seal (44). The sealing surface (24) gradually slopes outward in the direction facing the seal (44). The seal (44) has a mating surface (441) that seals with the sealing surface (24).

8. The shut-off valve according to claim 5, characterized in that, A sealing gasket (7) is provided between the valve body (1) and the valve cover (2).

9. The shut-off valve according to claim 7, characterized in that, It also includes a bracket (3) installed on the valve body (1), the bracket (3) pressing the valve cover (2) onto the valve body (1), and an adjustment pad (8) is provided between the bracket (3) and the valve cover (2).

10. The shut-off valve according to claim 9, characterized in that, The bracket (3) has a first threaded hole that is threadedly connected to the valve body (1). A threaded anti-loosening part is provided between the bracket (3) and the valve body (1). The threaded anti-loosening part includes a first through hole, a second blind hole and an anti-loosening bolt (32). The first through hole is formed on the bracket (3), and the second blind hole is formed on the valve body (1) and is correspondingly provided to the first through hole. One of the first through hole and the second blind hole is a second threaded hole, and the other hole is a mating hole. The anti-loosening bolt (32) is threadedly connected to the second threaded hole and is partially located in the mating hole.

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