Three-stage sealing structure for lining butterfly valve and lining butterfly valve thereof

Abstract

The utility model discloses a three-stage sealing structure for a lining butterfly valve and the lining butterfly valve thereof, which belong to the technical field of butterfly valves, and comprise an inelastic valve seat, a butterfly plate-valve rod assembly and a back ring, the back ring is arranged between the inelastic valve seat and a valve body, and the inelastic valve seat is provided with a first sealing part and a second sealing part. The butterfly plate-valve rod assembly comprises a first contact part and a second contact part, the first sealing part makes contact with the first contact part, the second sealing part makes contact with the second contact part, an O-shaped ring is arranged at the position, away from the first sealing part, of the second sealing part, and the butterfly plate-valve rod assembly is sleeved with the O-shaped ring. A first sealing part and a first contact part on the inelastic valve seat realize first-stage sealing; the second sealing part and the second contact part realize secondary sealing; and an O-shaped ring arranged at the tail end of the second sealing part realizes third-stage sealing. And finally, through three-stage sealing, good sealing performance of the lining butterfly valve is achieved, and good safety and reliability are achieved when the lining butterfly valve is used in the high-corrosivity and high-toxicity chemical industry.

Description

Technical Field

[0001] The utility model belongs to the technical field of butterfly valves, and in particular relates to a three-level sealing structure for a lined butterfly valve and a lined butterfly valve. Background Art

[0002] The butterfly valve, also called flap valve, is a simple regulating valve that can be used for the on-off control of low-pressure pipeline media. The butterfly valve refers to a valve whose closing part (valve disc or butterfly plate) is a disc that rotates around the valve axis to achieve opening and closing. The valve can be used to control the flow of various types of fluids such as air, water, steam, various corrosive media, mud, oil, liquid metal and radioactive media. It mainly plays the role of cutting off and throttling on the pipeline. The opening and closing part of the butterfly valve is a disc-shaped butterfly plate that rotates around its own axis in the valve body to achieve the purpose of opening, closing or regulating.

[0003] However, the existing lined butterfly valve has poor sealing performance. During use, the valve is frequently opened and closed, and the valve stem is prone to penetration over time. It is extremely unsafe for strong acid and strong alkali media. At the same time, users also generally report that the valve has disadvantages such as large operating torque.

[0004] The publication number is CN217003117U, and the publication date is a lined butterfly valve with a multiple sealing structure, including a valve body, a PTFE valve seat is arranged in the valve body, a valve shaft is connected to the top of the valve body, a butterfly plate is connected to the valve shaft, and the butterfly plate is arranged in the PTFE valve seat; a chamber is arranged between the valve shaft and the valve body, three sleeves are arranged in the chamber, and the sleeves are interference fit with the valve body and the valve shaft; a sealing gasket is arranged on the valve shaft, an annular butterfly spring is arranged in the sealing gasket, a pressure steel sleeve is arranged at the lower end of the butterfly spring, and a sealing ring and a sealing ring are arranged between the pressure steel sleeve and the valve shaft. Utility Model Content

[0005] In order to solve the above technical problems, the utility model provides a three-stage sealing structure for a lined butterfly valve and a lined butterfly valve thereof, wherein the first sealing part on the non-elastic valve seat and the first contact part realize the first-stage sealing; the second sealing part and the second contact part realize the second-stage sealing; and the O-ring arranged at the end of the second sealing part realizes the third-stage sealing. Finally, through the three-stage sealing, the good sealing performance of the lined butterfly valve is achieved, and it has good safety and reliability when used in highly corrosive and highly toxic chemical industries. The utility model has the advantages of small overall volume, simple and reliable structure, convenient problem finding, easy replacement, and no need for additional installation tools.

[0006] The purpose of this utility model is achieved through the following technical solutions:

[0007] The lined butterfly valve uses a three-stage sealing structure, including a non-elastic valve seat, a butterfly plate-valve stem assembly and a back ring, the back ring is arranged between the non-elastic valve seat and the valve body, the non-elastic valve seat is provided with a first sealing portion and a second sealing portion, the butterfly plate-valve stem assembly includes a first contact portion and a second contact portion, the first sealing portion is in contact with the first contact portion, the second sealing portion is in contact with the second contact portion, the second sealing portion is provided with an O-ring away from the first sealing portion, and the O-ring is sleeved on the butterfly plate-valve stem assembly.

[0008] Preferably, the second sealing portion is a barrel-shaped structure.

[0009] Preferably, the diameter of the second sealing portion is smaller than the diameter of the butterfly plate-valve stem assembly.

[0010] Preferably, an accommodating cavity is provided between the non-elastic valve seat and the valve body, and a thrust ring, an elastic gasket and a leaf spring are sequentially arranged in the accommodating cavity, and the thrust ring is arranged close to the first sealing portion.

[0011] Preferably, PTFE gaskets are arranged between the thrust ring and the elastic gasket, between the elastic gasket and the leaf spring, and at the end of the leaf spring away from the elastic gasket.

[0012] Preferably, an O-ring placement groove is provided between the second sealing portion and the thrust ring.

[0013] The lined butterfly valve comprises a valve body, wherein a non-elastic valve seat is arranged in the valve body, a through hole matching with a butterfly plate-valve stem assembly is arranged on the non-elastic valve seat, and a three-level sealing structure is arranged at the through hole.

[0014] Preferably, a sliding bearing is provided between the butterfly plate-valve stem assembly and the valve body.

[0015] Preferably, a clamping ring is sleeved on the butterfly plate-valve stem assembly.

[0016] The beneficial effects of this technical solution are as follows:

[0017] 1. The lined butterfly valve provided by the utility model has a three-stage sealing structure. The first sealing part and the first contact part on the non-elastic valve seat realize the first-stage sealing; the second sealing part and the second contact part realize the second-stage sealing; the O-ring arranged at the end of the second sealing part realizes the third-stage sealing. Finally, through the three-stage sealing, the good sealing performance of the lined butterfly valve is achieved, and it has good safety and reliability when used in highly corrosive and highly toxic chemical industries. The elastic back ring between the non-elastic valve seat and the valve body plays an elastic squeezing role. Through the elasticity of the back ring, the interference fit between the non-elastic valve seat and the butterfly plate-stem assembly is achieved, and finally the butterfly valve is shut off and sealed to the pipeline fluid. The utility model has the advantages of small overall volume, simple structure, reliability, convenient problem finding, easy replacement, and no need for additional installation tools.

[0018] 2. The utility model provides a three-stage sealing structure for the lined butterfly valve, which realizes the first stage of sealing by squeezing the thrust ring through the leaf spring and the elastic gasket, and pushing the non-elastic valve seat and the butterfly plate-stem assembly at the perforation; the non-elastic valve seat forms a cylindrical structure along the butterfly plate-stem assembly at the perforation, and the diameter is smaller than the value diameter of the butterfly plate-stem assembly, and is assembled at high temperature to realize the second stage of sealing; an O-ring is added to the end of the second sealing part on the non-elastic valve seat, and the thrust ring is pushed by the elastic gasket and the leaf spring to squeeze the O-ring to realize the third stage of sealing.

[0019] 3. The lined butterfly valve provided by the utility model has good sealing performance through three-level sealing, and has good safety and reliability when used in highly corrosive and highly toxic chemical industries. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a structural schematic diagram of a three-stage sealing structure for a lined butterfly valve of the utility model;

[0021] Figure 2 It is a structural schematic diagram of the valve seat in the utility model;

[0022] Figure 3 This is a structural schematic diagram of the butterfly plate-valve stem assembly in the utility model;

[0023] Figure 4 The structure of the lined butterfly valve in Example 3 of the utility model is shown in FIG. Figure 1 ;

[0024] Figure 5 The structure of the lined butterfly valve in Example 3 of the utility model is shown in FIG. Figure 2 ;

[0025] Figure 6 This is a schematic diagram of the structure of the lined butterfly valve in Example 4 of the utility model;

[0026] Figure 7 This is a schematic diagram of the structure of the lined butterfly valve in Example 5 of the utility model;

[0027] In the figure: 10, non-elastic valve seat; 11, first sealing part; 12, second sealing part; 20, butterfly plate-stem assembly; 21, first contact part; 22, second contact part; 30, O-ring; 31, O-ring placement groove; 40, accommodating chamber; 50, thrust ring; 60, elastic gasket; 70, leaf spring; 80, PTFE gasket; 90, valve body; 110, sliding bearing; 120, retaining ring; 130, valve body cover plate; 140, sealing gasket; 150, pivot pin; 160, primary sealing accommodating chamber; 170, back ring. DETAILED DESCRIPTION

[0028] The present invention is further described in detail below in conjunction with the embodiments, but the implementation manner of the present invention is not limited thereto.

[0029] Example 1

[0030] like Figure 1-Figure 3 As shown, the lined butterfly valve uses a three-stage sealing structure, including a non-elastic valve seat 10, a butterfly plate-valve stem assembly 20 and a back ring 170, the back ring 170 is arranged between the non-elastic valve seat 10 and the valve body 90, the non-elastic valve seat 10 is provided with a first sealing portion 11 and a second sealing portion 12, the butterfly plate-valve stem assembly 20 includes a first contact portion 21 and a second contact portion 22, the first sealing portion 11 is in contact with the first contact portion 21, the second sealing portion 12 is in contact with the second contact portion 22, the second sealing portion 12 is provided with an O-ring 30 away from the first sealing portion 11, and the O-ring 30 is sleeved on the butterfly plate-valve stem assembly 20.

[0031] The first sealing part 11 on the non-elastic valve seat 10 and the first contact part 21 realize the first-level sealing; the second sealing part 12 and the second contact part 22 realize the second-level sealing; the O-ring 30 arranged at the end of the second sealing part 12 realizes the third-level sealing. Finally, through the three-level sealing, the good sealing performance of the lined butterfly valve is achieved, and it has good safety and reliability when used in highly corrosive and highly toxic chemical industries. The elastic back ring 170 that plays an elastic squeezing role between the non-elastic valve seat 10 and the valve body 90 realizes the interference fit between the non-elastic valve seat 10 and the butterfly plate-valve stem assembly 20 through the elasticity of the back ring 170, and finally realizes the shutoff and sealing of the pipeline fluid by the butterfly valve. The utility model has the advantages of small overall volume, simple structure, reliability, convenient problem finding, easy replacement, and no need for additional installation tools.

[0032] Example 2

[0033] The difference between this embodiment and embodiment 1 is that the second sealing portion 12 is a barrel-shaped structure.

[0034] The diameter of the second sealing portion 12 is smaller than the diameter of the butterfly plate-valve stem assembly 20 .

[0035] An accommodating chamber 40 is provided between the non-elastic valve seat 10 and the valve body 90 . A thrust ring 50 , an elastic gasket 60 and a leaf spring 70 are sequentially arranged in the accommodating chamber 40 . The thrust ring 50 is arranged close to the first sealing portion 11 .

[0036] Among them, PTFE gaskets 80 are arranged between the thrust ring 50 and the elastic gasket 60 , between the elastic gasket 60 and the leaf spring 70 , and at the end of the leaf spring 70 away from the elastic gasket 60 .

[0037] A groove for placing the O-ring 30 is provided between the second sealing portion 12 and the thrust ring 50 .

[0038] The thrust ring 50 is squeezed by the leaf spring 70 and the elastic gasket 60 to push the non-elastic valve seat 10 and the butterfly plate-valve stem assembly 20 at the perforation to achieve the first-level sealing; the non-elastic valve seat 10 forms a cylindrical structure along the butterfly plate-valve stem assembly 20 at the perforation, and the diameter is smaller than the value diameter of the butterfly plate-valve stem assembly 20, and is assembled at high temperature to achieve the second-level sealing; an O-ring 30 is added to the end of the second sealing part 12 on the non-elastic valve seat 10, and the thrust ring 50 is pushed by the elastic gasket 60 and the leaf spring 70 to squeeze the O-ring 30 to achieve the third-level sealing.

[0039] Example 3

[0040] like Figure 4 and Figure 5 As shown, the lined butterfly valve includes a valve body 90, in which a non-elastic valve seat 10 is arranged, and the non-elastic valve seat 10 is provided with perforations matching the butterfly plate-valve stem assembly 20, and the perforations are two, and a three-level sealing structure is provided at the perforations; the three-level sealing structure adopts the structure described in Example 2; the butterfly plate-valve stem assembly 20 adopts an integrated PFA-coated butterfly plate + valve stem.

[0041] Wherein, a sliding bearing 110 is arranged between the butterfly plate-valve stem assembly 20 and the valve body 90 .

[0042] The butterfly plate-valve stem assembly 20 is sleeved with a clamping ring 120 . The clamping ring 120 is arranged above the non-elastic valve seat 10 .

[0043] The diameter of the lined butterfly valve is DN200-DN600, and an opening is arranged at the lower end of the valve body 90, and a sealing gasket and a valve body cover plate are arranged at the opening.

[0044] Example 4

[0045] like Figure 6 As shown, the difference between this embodiment and embodiment 3 is that: the diameter of the lined butterfly valve is DN65-DN150; a pivot pin is arranged at the lower end of the butterfly plate-valve stem assembly 20, and the pivot pin passes through the thrust ring 50, the elastic gasket 60 and the leaf spring 70 in sequence, and the thrust ring 50 is arranged close to the first sealing portion 11; PTFE gaskets 80 are arranged between the thrust ring 50 and the elastic gasket 60, between the elastic gasket 60 and the leaf spring 70, and at the end of the leaf spring 70 away from the elastic gasket 60; the butterfly plate-valve stem assembly 20 adopts an integrated butterfly plate + valve stem.

[0046] Example 5

[0047] like Figure 7As shown, the difference between this embodiment and embodiment 3 is that: the diameter of the lined butterfly valve is DN40-DN50, the upper end of the non-elastic valve seat 10 is provided with a perforation matching the butterfly plate-stem assembly 20, the perforation is one, and a three-level sealing structure is provided at the perforation; a primary sealing accommodating cavity is provided on the butterfly plate-stem assembly 20 at the lower end of the perforation, and a thrust ring 50, an elastic gasket 60 and a leaf spring 70 are arranged in sequence in the primary sealing accommodating cavity, and the thrust ring 50 is arranged close to the first sealing portion 11; PTFE gaskets 80 are arranged between the thrust ring 50 and the elastic gasket 60, between the elastic gasket 60 and the leaf spring 70, and at the end of the leaf spring 70 away from the elastic gasket 60; the butterfly plate-stem assembly 20 adopts an integrated butterfly plate + valve stem.

[0048] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Any simple modification or equivalent changes made to the above embodiments based on the technical essence of the present invention shall fall within the protection scope of the present invention.

Claims

1. The three-stage sealing structure of the lined butterfly valve is characterized by: The invention comprises a non-elastic valve seat (10), a butterfly plate-valve stem assembly (20) and a back ring (170), wherein the back ring (170) is arranged between the non-elastic valve seat (10) and the valve body (90), the non-elastic valve seat (10) is provided with a first sealing portion (11) and a second sealing portion (12), the butterfly plate-valve stem assembly (20) comprises a first contact portion (21) and a second contact portion (22), the first sealing portion (11) is in contact with the first contact portion (21), the second sealing portion (12) is in contact with the second contact portion (22), an O-ring (30) is arranged at a position of the second sealing portion (12) away from the first sealing portion (11), and the O-ring (30) is sleeved on the butterfly plate-valve stem assembly (20).

2. The three-stage sealing structure for a lined butterfly valve according to claim 1 is characterized in that: The second sealing portion (12) is a barrel-shaped structure.

3. The three-stage sealing structure for a lined butterfly valve according to claim 1 is characterized in that: The diameter of the second sealing portion (12) is smaller than the diameter of the butterfly plate-valve stem assembly (20).

4. The three-stage sealing structure for a lined butterfly valve according to claim 1 is characterized in that: An accommodating chamber (40) is provided between the non-elastic valve seat (10) and the valve body (90), and a thrust ring (50), an elastic gasket (60) and a leaf spring (70) are sequentially arranged in the accommodating chamber (40), wherein the thrust ring (50) is arranged close to the first sealing portion (11).

5. The three-stage sealing structure for a lined butterfly valve according to claim 4 is characterized in that: PTFE gaskets (80) are arranged between the thrust ring (50) and the elastic gasket (60), between the elastic gasket (60) and the leaf spring (70), and at the end of the leaf spring (70) away from the elastic gasket (60).

6. The three-stage sealing structure for a lined butterfly valve according to claim 1 is characterized in that: An O-ring placement groove is provided between the second sealing portion (12) and the thrust ring (50).

7. A lined butterfly valve, comprising a valve body (90), wherein a non-elastic valve seat (10) is arranged in the valve body (90), and a perforation matching a butterfly plate-valve stem assembly (20) is arranged on the non-elastic valve seat (10), characterized in that: The perforation is provided with a three-level sealing structure.

8. The lined butterfly valve according to claim 7, characterized in that: A sliding bearing (110) is provided between the butterfly plate-valve stem assembly (20) and the valve body (90).

9. The lined butterfly valve according to claim 8, characterized in that: A clamping ring (120) is sleeved on the butterfly plate-valve stem assembly (20).

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