Low-leakage combined packing structure

Abstract

The utility model discloses a low-leakage combined type packing structure, and relates to the technical field of sealing packing, the low-leakage combined type packing structure comprises a first packing, a second packing and a third packing which are stacked in sequence, and two sealing rings are arranged between the first packing and the second packing; an air bag ring is arranged between the second filler and the third filler, and a containing groove matched with the air bag ring is formed in the end face of the second filler; and the second filler consists of an upper filler pad, a plurality of middle filler pads and a lower filler pad. By arranging the multi-layer packing stacking structure, the defect that the sealing performance of single-layer packing is insufficient can be overcome, the advantages of all layers of packing can be fully played, the overall sealing performance is effectively improved, and medium leakage is prevented.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of sealing packing, in particular to a low-leakage combined packing structure. BACKGROUND

[0002] Valves play a vital role in fluid systems, and their sealing performance is directly related to the safety and efficiency of production. Packing sealing is an important form of valve sealing technology. The existing packing used by valves is single in type, which makes the sealing performance of the existing packing still unable to reach the best state, which may cause medium leakage.

[0003] Therefore, it is an urgent problem to design a valve packing sealing structure with high sealing performance. CONTENT OF THE INVENTION

[0004] Therefore, the present application provides a low-leakage combined packing structure to solve the technical problem that the sealing performance of the existing packing is unstable and may cause medium leakage.

[0005] To achieve the above-mentioned purpose, the present application provides the following technical solutions:

[0006] A low-leakage packing sealing structure for a valve, comprising a first packing, a second packing and a third packing stacked in sequence, two sealing rings are arranged between the first packing and the second packing, a gas bag ring is arranged between the second packing and the third packing, and a containing groove matched with the gas bag ring is arranged on an end face of the second packing.

[0007] Further, the first packing comprises a first trapezoidal cross-section packing ring and a second trapezoidal cross-section packing ring, one end of the second trapezoidal cross-section packing ring close to the first trapezoidal cross-section packing ring has a conical boss part, and a conical hole part matched with the conical boss part is arranged on the first trapezoidal cross-section packing ring.

[0008] Further, the second packing comprises:

[0009] an upper packing pad, a gap groove is arranged at the groove bottom of a groove structure with an inverted V-shaped cross section arranged on the lower end face of the upper packing pad, and a corresponding groove for installing the corresponding sealing ring is arranged on the top of the upper packing pad;

[0010] a plurality of middle packing pads, the cross section of the middle packing pad is arc-shaped, and the middle packing pad adjacent to the upper packing pad can be pressed into the groove structure;

[0011] a lower packing pad, the top of the lower packing pad has an arc-shaped protruding part capable of cooperating with the adjacent middle packing pad.

[0012] Further, the first trapezoidal cross-section packing ring and the second trapezoidal cross-section packing ring are provided with an elastic pad with uniform thickness.

[0013] Further, the two sealing rings are respectively a first sealing ring and a second sealing ring, the first groove matched with the first sealing ring is located at the inner side of the second groove matched with the second sealing ring, and the cross section of the groove is L-shaped.

[0014] Further, the number of the middle packing pads is three.

[0015] Further, the sealing ring is composed of a rubber gasket, an anti-corrosion layer wrapped around the outer periphery of the rubber gasket, a wear-resistant layer wrapped around the outer periphery of the anti-corrosion layer, and a high-temperature-resistant layer wrapped around the outer periphery of the wear-resistant layer.

[0016] Further, the first packing is a flexible graphite molded packing, the second packing is a polytetrafluoroethylene packing, and the third packing is a flexible graphite woven packing.

[0017] Further, the air bag ring is annular and coaxial with the second packing.

[0018] From the above technical solution, the advantages of the present application are:

[0019] 1. The present application stacks and combines the flexible graphite molded packing, the polytetrafluoroethylene packing and the flexible graphite woven packing with high performance together, thereby enhancing the sealing performance of the whole packing.

[0020] 2. The air bag ring of the present application is provided inside, and the gas inside the air bag ring will expand when heated, thereby improving the radial sealing effect of the packing combination assembly.

[0021] 3. The inverted V-shaped groove structure provided on the lower end surface of the upper packing pad and the arc-shaped protruding part provided on the top of the lower sealing pad can cooperate with the adjacent middle packing pad, and the middle packing pad will deform and automatically compensate to form a tight sealing interface after being extruded by the outside, thereby further improving the airtightness of the packing assembly. BRIEF DESCRIPTION OF DRAWINGS

[0022] The drawings constituting a part of the present application are used to provide a further understanding of the present application, and the schematic embodiments of the present application and the description thereof are used to explain the present application and do not constitute an improper limitation on the present application.

[0023] Figure 1 It is an exploded structure schematic diagram of the present application.

[0024] Figure 2 It is a front view cross-sectional structure schematic diagram of the present application.

[0025] Figure 3 It is Figure 2a partial enlarged view of the first packing.

[0026] Figure 4 is Figure 2 a partial enlarged view of the second packing.

[0027] Figure 5 is a schematic view of the material layer of the first sealing ring.

[0028] Legend: 1-first packing; 11-first trapezoidal cross-section packing ring; 12-elastic pad; 13-second trapezoidal cross-section packing ring; 2-second packing; 21-upper packing pad; 211-first groove; 212-second groove; 213-gap groove; 22-middle packing pad; 23-lower packing pad; 231-receiving groove; 3-third packing; 4-first sealing ring; 5-second sealing ring; 6-air bag ring; 701-rubber gasket; 702-corrosion-resistant layer; 703-abrasion-resistant layer; 704-high-temperature-resistant layer. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solutions and advantages of the present application clearer, the present application is further described in detail below in conjunction with the embodiments and drawings. Herein, the illustrative embodiments of the present application and their descriptions are used to explain the present application, but not as a limitation to the present application.

[0030] Reference Figures 1 to 5 As Figure 1 shown, the present embodiment provides a low-leakage combined packing structure, comprising: first packing 1, second packing 2 and third packing 3 stacked in sequence, two sealing rings are arranged between the first packing 1 and the second packing 2, an air bag ring 6 is arranged between the second packing 2 and the third packing 3, a receiving groove 231 is arranged on the end face of the second packing 2 and cooperates with the air bag ring 6, and the air bag ring 6 is arranged coaxially with the second packing 2 in a ring shape.

[0031] When the packing assembly is filled in the valve packing cavity, the valve flows through the high-temperature medium or the indoor temperature rises, the gas inside the air bag ring 6 expands and expands, thereby improving the axial sealing effect of the packing combination assembly.

[0032] In an embodiment, as Figure 3 shown, the first packing 1 comprises a first trapezoidal cross-section packing ring 11 and a second trapezoidal cross-section packing ring 13, one end of the second trapezoidal cross-section packing ring 13 close to the first trapezoidal cross-section packing ring 11 has a conical boss part, and the first trapezoidal cross-section packing ring 11 is provided with a conical hole part matched with the conical boss part.

[0033] In an embodiment, as Figure 4As shown, the second packing 2 comprises: an upper packing pad 21, a plurality of middle packing pads 22 and a lower packing pad 23, the lower end surface of the upper packing pad 21 is provided with a groove structure in inverted V-shaped cross section, the groove bottom of the groove structure is provided with a gap groove 213, the top of the upper packing pad 21 is provided with a corresponding groove for mounting the corresponding sealing ring; the cross section of the middle packing pad 22 is in arc shape, the middle packing pad 22 adjacent to the upper packing pad 21 can be pressed into the groove structure; the top of the lower packing pad 23 has an arc-shaped protruding portion capable of cooperating with the adjacent middle packing pad 22. The central angle of the inverted V-shaped structure of the upper packing pad 21 is smaller than the central angle of the arc-shaped protruding portion of the middle packing pad 22 to increase the deformation amount of the middle packing pad 22 when pressed and improve the sealing compensation performance of the middle packing pad 22. The middle packing pad 22 enhances the sealing effect during use by being arranged in layers, and the three-layer packing pad combination structure of the second packing 2 cooperates with each other to form a tight sealing interface.

[0034] In an embodiment, as shown in the drawings, the first trapezoidal cross-section packing ring 11 and the second trapezoidal cross-section packing ring 13 are provided with an elastic pad 12 with uniform thickness, and the elastic force of the elastic pad 12 can increase the axial sealing force of the combined packing. Figure 3

[0035] Specifically, the elastic pad 12 is made of rubber material.

[0036] In an embodiment, as shown in the drawings, the two sealing rings are respectively a first sealing ring 4 and a second sealing ring 5, the first groove 211 cooperating with the first sealing ring 4 is located inside the second groove 212 cooperating with the second sealing ring 5, and the cross section of the groove is in L shape. Figure 4 In this embodiment, the number of middle packing pads 22 is increased or decreased according to the size of the valve packing chamber, and is preferably three.

[0037] Specifically, as shown in the drawings, the sealing ring is composed of a rubber gasket 701, a corrosion-resistant layer 702 wrapped around the outer periphery of the rubber gasket 701, a wear-resistant layer 703 wrapped around the outer periphery of the corrosion-resistant layer 702, and a high-temperature-resistant layer 704 wrapped around the outer periphery of the wear-resistant layer 703.

[0038] Figure 5 The corrosion-resistant layer 702 is made of zinc-nickel alloy material, which has excellent corrosion resistance and good formability and tensile properties, can improve the corrosion resistance of the sealing ring, and thus effectively improve the service life of the sealing ring.

[0039] The wear-resistant layer 703 is made of PU polyurethane rubber material.

[0040] The wear-resistant layer 703 is made of PU polyurethane rubber material.

[0041] ​​The high-temperature-resistant layer 704 is made of polytetrafluoroethylene material, and the polytetrafluoroethylene has excellent heat resistance and cold resistance, so that the high-temperature-resistant performance of the sealing ring is effectively improved, and the stability of the sealing ring in a high-temperature environment is improved.

[0042] Specifically, the first filler 1 is a flexible graphite mold filling material, the second filler 2 is a polytetrafluoroethylene filler, and the third filler 3 is a flexible graphite woven filler.

[0043] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. Those skilled in the art can make various modifications and changes to the embodiments of the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A low leakage combined packing structure, characterized in that: The invention comprises a first filler (1), a second filler (2) and a third filler (3) stacked in sequence, two sealing rings being provided between the first filler (1) and the second filler (2), an air bag ring (6) being provided between the second filler (2) and the third filler (3), and a receiving groove (231) cooperating with the air bag ring (6) being provided on the end surface of the second filler (2).

2. A low leakage combined packing structure according to claim 1, characterized in that: The first packing (1) comprises a first trapezoidal cross-section packing ring (11) and a second trapezoidal cross-section packing ring (13), wherein the second trapezoidal cross-section packing ring (13) has a conical boss portion at one end close to the first trapezoidal cross-section packing ring (11), and the first trapezoidal cross-section packing ring (11) is provided with a conical hole portion that cooperates with the conical boss portion.

3. A low leakage combined packing structure according to claim 1, characterized in that: The second filler (2) comprises: An upper packing pad (21), wherein a groove structure having an inverted V-shaped cross section is provided on the lower end surface of the upper packing pad (21), a gap groove (213) is provided at the bottom of the groove structure, and a corresponding groove for mounting the corresponding two sealing rings is provided on the top of the upper packing pad (21); a plurality of middle filling pads (22), wherein the cross section of the middle filling pads (22) is arc-shaped, and the middle filling pads (22) adjacent to the upper filling pad (21) can be pressed into the groove structure; A lower packing pad (23) has an arc-shaped protrusion on the top thereof that can cooperate with the adjacent middle packing pad (22).

4. A low leakage combined packing structure according to claim 2, characterized in that: An elastic pad (12) with uniform thickness is provided between the first trapezoidal cross-section packing ring (11) and the second trapezoidal cross-section packing ring (13).

5. The low leakage combined packing structure according to claim 3, characterized in that: The two sealing rings are respectively a first sealing ring (4) and a second sealing ring (5); a first groove (211) cooperating with the first sealing ring (4) is located inside a second groove (212) cooperating with the second sealing ring (5); and the cross section of the groove is L-shaped.

6. The low leakage combined packing structure according to claim 3, characterized in that: The number of the middle filling pads (22) is 3.

7. The low leakage combined packing structure according to claim 5, characterized in that: The sealing ring is composed of a rubber gasket (701), an anti-corrosion layer (702) wrapped around the outer periphery of the rubber gasket (701), a wear-resistant layer (703) wrapped around the outer periphery of the anti-corrosion layer (702), and a high-temperature resistant layer (704) wrapped around the outer periphery of the wear-resistant layer (703).

8. The low leakage combined packing structure according to claim 1, characterized in that: The first filler (1) is a flexible graphite molded filler, the second filler (2) is a polytetrafluoroethylene filler, and the third filler (3) is a flexible graphite braided filler.

9. The low leakage combined packing structure according to claim 1, characterized in that: The airbag ring (6) is in the shape of a ring and is coaxially arranged with the second filler (2).

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