Multi-stage sealing structure for valve plate closing mechanism

Abstract

The utility model discloses a multistage sealing structure for a valve plate closing mechanism, which comprises a valve plate a, a valve seat a and a connecting sleeve, a torsion spring is arranged on the connecting sleeve, the valve plate a is connected with the torsion spring through a rotating pin, the torsion spring is used for closing the valve plate a and the valve seat a, and a composite sealing ring is abutted between the valve plate a and the valve seat a. And the valve plate a, the valve seat a and the composite sealing ring are jointly sealed. The sealing performance is improved by arranging the inelastic composite sealing ring between the valve plate and the valve seat, a double-layer sealing structure is arranged on the composite sealing ring, a single-layer sealing structure is arranged on the valve seat, and the three layers of sealing structures are matched with the sealing surface of the valve plate, so that the sealing performance is improved. The technical problem that in the prior art, a valve plate closing structure is poor in sealing effect when a valve plate is closed is solved.

Description

Technical Field

[0001] The utility model belongs to the technical field of petroleum and natural gas downhole tools and relates to a multi-stage sealing structure for a valve plate closing mechanism. Background Art

[0002] At present, the one-way flapper valve used in downhole testing and completion operations generally uses a metal seal between a flat valve plate and a flat valve seat for the multi-stage sealing structure of the valve plate closing mechanism. The pressure squeezes the valve plate to further fit the plane of the valve seat to isolate the fluid. When it is only used to shut off a large flow of fluid, the sealing requirements for the valve plate are not strict. Only relying on metal sealing can ensure the shut-off effect of the fluid at low pressure. However, as a safety valve for testing or a shut-off valve for checking sealing, the effect is not good, so the valve plate type closing mechanism cannot completely replace the ball valve type structure in terms of sealing. Therefore, there is an urgent need for a multi-stage sealing structure for a valve plate closing mechanism that can ensure the sealing after the valve plate is closed. Utility Model Content

[0003] The utility model aims to provide a multi-stage sealing structure for a valve plate closing mechanism, which solves the technical problem of poor sealing effect after the valve plate is closed in the prior art.

[0004] The technical solution adopted by the utility model is a multi-stage sealing structure for a valve plate closing mechanism, including a valve plate a, a valve seat a and a connecting sleeve, a torsion spring is provided on the connecting sleeve, the valve plate a is connected to the torsion spring by a turn pin, the torsion spring is used to close the valve plate a and the valve seat a, a composite sealing ring is abutted between the valve plate a and the valve seat a, and the valve plate a is sealed together with the valve seat a and the composite sealing ring.

[0005] The utility model is characterized in that:

[0006] The composite sealing ring is sleeved on the valve seat a, and the composite sealing ring includes a first sealing surface and a second sealing surface. The valve seat a includes a third sealing surface. The second sealing surface and the third sealing surface are both conical surfaces and form a seal with the valve plate a together. The first sealing surface forms a seal with the plane of the valve plate a.

[0007] The sealing surface of the valve plate a is a spherical arc surface, and the spherical arc surface, the second sealing surface and the third sealing surface form a seal together.

[0008] The spherical arc surface of the valve plate a forms a linear seal with the second sealing surface and the third sealing surface.

[0009] The third sealing surface is a metal sealing surface.

[0010] An annular protrusion is arranged on the first sealing surface.

[0011] A groove is provided on the composite sealing ring, and a spring ring which is in a U shape as a whole is arranged in the groove.

[0012] An annular relief groove is provided on the side where the composite sealing ring contacts the valve seat a.

[0013] The beneficial effects of the utility model are:

[0014] The utility model improves the sealing performance by arranging a non-elastic composite sealing ring between the valve plate and the valve seat, and by arranging a double-layer sealing structure on the composite sealing ring and a single-layer sealing structure on the valve seat. A total of three-layer sealing structures cooperate with the sealing surface of the valve plate, thereby solving the technical problem in the prior art that the valve plate closing structure has a poor sealing effect when the valve plate is closed. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a structural schematic diagram of the valve plate closing structure of the utility model;

[0016] Figure 2 yes Figure 1 The structural diagram at A in the middle;

[0017] Figure 3 It is a structural schematic diagram of the valve plate a in the valve plate closing structure of the utility model in an open state;

[0018] Figure 4 It is a structural schematic diagram of a composite sealing ring in a valve plate closing structure of the utility model;

[0019] Figure 5 yes Figure 4 The structural diagram at B in the middle;

[0020] Figure 6 It is a schematic diagram of the structure in which the valve seat b and the valve plate b are closed in the valve plate closing structure of the prior art;

[0021] Figure 7 It is a schematic diagram of the structure in which the valve seat b and the valve plate b are opened in the valve plate closing structure of the prior art;

[0022] In the figure, 1. valve plate a, 2. valve seat a, 3. turn pin, 4. torsion spring, 5. composite sealing ring, 6. spring ring, 7. first sealing surface, 8. second sealing surface, 9. connecting sleeve, 10. release groove, 11. annular protrusion, 12. third sealing surface, 13. valve seat b, 14. valve plate b, 15. fourth sealing surface. DETAILED DESCRIPTION

[0023] The utility model is further described below in conjunction with the accompanying drawings and specific implementation methods.

[0024] Example 1

[0025] like Figure 1 and Figure 3As shown, the utility model provides a multi-stage sealing structure for a valve plate closing mechanism, including a valve plate a1, a valve seat a2 and a connecting sleeve 9, the connecting sleeve 9 is provided with a torsion spring 4, the valve plate a1 is connected to the torsion spring 4 by a turn pin 3, the torsion spring 4 is used to close the valve plate a1 and the valve seat a2, a composite sealing ring 5 is abutted between the valve plate a1 and the valve seat a2, and the valve plate a1 is sealed together with the valve seat a2 and the composite sealing ring 5.

[0026] The utility model improves the sealing performance by arranging a non-elastic composite sealing ring 5 between the valve plate a1 and the valve seat a2, thereby avoiding the following problems: Figure 6 and Figure 7 The multi-stage sealing structure for the valve plate closing mechanism in the prior art shown has only a planar sealing structure, which causes the problem of poor sealing between the valve plate b14 and the valve seat b13 after the valve plate b14 is closed. The reason is that the fourth sealing surface 15 is a plane, which makes sealing more difficult.

[0027] Example 2

[0028] On the basis of Example 1, Figure 4 and Figure 5 As shown, the composite sealing ring 5 is sleeved on the valve seat a2, the composite sealing ring 5 includes a first sealing surface 7 and a second sealing surface 8, the valve seat a2 includes a third sealing surface 12, the second sealing surface 8 and the third sealing surface 12 are both conical surfaces and form a seal with the valve plate a1 together, and the first sealing surface 7 forms a seal with the plane of the valve plate a1.

[0029] The sealing surface of the valve plate a1 is a spherical arc surface, which forms a seal together with the second sealing surface 8 and the third sealing surface 12 .

[0030] like Figure 2 As shown, position Ⅰ is the extrusion contact seal between the plane of the valve plate a1 and the first sealing surface 7 of the composite sealing ring 5, position Ⅱ is the interference seal between the spherical arc surface of the valve plate a1 and the second sealing surface 8 of the composite sealing ring 5, and position Ⅲ is the contact seal between the spherical arc surface of the valve plate a1 and the third sealing surface 12 of the valve seat a2.

[0031] The valve plate a1 adopts a double sealing surface of an arc-shaped curved surface and a plane. The plane of the valve plate a1 and the end of the composite sealing ring 5 form the first hard-soft sealing structure; the arc-shaped curved surface of the valve plate a1 and the conical surface of the composite sealing ring 5 produce an interference seal, forming the second hard-soft sealing structure; the arc-shaped curved surface of the valve plate a1 and the metal conical surface of the valve seat a2 produce a metal hard seal, forming the third hard-hard sealing structure, which is also the main high-pressure sealing bearing structure.

[0032] The spherical arc surface of the valve plate a1 forms a linear seal with the second sealing surface 8 and the third sealing surface 12 .

[0033] The third sealing surface 12 is a metal sealing surface.

[0034] The arc surface of the valve plate a1 is actually a spherical curved surface, and forms a linear seal with the metal cone surface of the valve seat a2. When the valve plate a1 is closed, the valve plate a1 produces a slight deflection in any direction of the circumference, which can also ensure the sealing design of the ball and the cone.

[0035] An annular protrusion 11 is provided on the first sealing surface 7 .

[0036] The annular protrusion 11 of the composite sealing ring 5 increases the local stress in contact with the valve plate a1, thereby improving the sealing performance.

[0037] Example 3

[0038] On the basis of Example 1, a groove is formed on the composite sealing ring 5, and a spring ring 6 which is generally U-shaped is arranged in the groove.

[0039] After the valve plate is repeatedly opened and closed, the sealing ring is compressed by the spring, which provides reliable mechanical support to ensure the interference fit design of the outer circle of the sealing ring. And under the pressure, the end seal corresponding to this part will be pressed tighter and tighter to ensure the sealing performance.

[0040] An annular release groove 10 is formed on the side of the composite sealing ring 5 that contacts the valve seat a2.

[0041] The annular release groove 10 between the composite sealing ring 5 and the valve seat a2 provides a release area for the composite sealing ring 5 to be squeezed and deformed.

[0042] The utility model is a multi-stage sealing structure for the valve plate closing mechanism, which can be widely used in downhole testing and well completion of the valve plate type tools, such as tubing pressure test valve, squeeze valve, safety valve type baffle valve structure tools. The three-line sealing design of the valve plate a1 improves the reliability of the seal; the composite sealing ring 5 not only seals but also provides a shock-absorbing function for the closing of the valve plate a1; the U-shaped spring ring 6 design on the composite sealing ring 5 ensures the interference fit design of the composite sealing ring 5 after repeated use; the annular protrusion 11 of the composite sealing ring 5 increases the local stress in contact with the valve plate a1 and improves the sealing performance; the annular release groove 10 between the composite sealing ring 5 and the valve seat a2 provides a release area for the extrusion deformation of the composite sealing ring 5, and the structural design is more reasonable, which improves the service life. The cooperation between the arc surface of the valve plate a1 and the conical surface of the valve seat a2 reduces the precision requirements for the assembly of the valve plate a1 and the valve seat a2, reduces the processing difficulty, and improves the reliability of product performance.

Claims

1. A multi-stage sealing structure for a valve plate closing mechanism, comprising a valve plate a (1), a valve seat a (2) and a connecting sleeve (9), wherein a torsion spring (4) is provided on the connecting sleeve (9), the valve plate a (1) is connected to the torsion spring (4) via a rotating pin (3), and the torsion spring (4) is used to close the valve plate a (1) and the valve seat a (2), wherein the torsion spring (4) is used to close the valve plate a (1) and the valve seat a (2), wherein: A composite sealing ring (5) is abutted between the valve plate a (1) and the valve seat a (2), and the valve plate a (1), the valve seat a (2) and the composite sealing ring (5) are sealed together.

2. The multi-stage sealing structure for a valve plate closing mechanism according to claim 1, characterized in that: The composite sealing ring (5) is sleeved on the valve seat a (2), the composite sealing ring (5) comprises a first sealing surface (7) and a second sealing surface (8), the valve seat a (2) comprises a third sealing surface (12), the second sealing surface (8) and the third sealing surface (12) are both conical surfaces and form a seal with the valve plate a (1) together, and the first sealing surface (7) forms a seal with the plane of the valve plate a (1).

3. The multi-stage sealing structure for a valve plate closing mechanism according to claim 2, characterized in that: The sealing surface of the valve plate a (1) is a spherical arc surface, and the spherical arc surface, the second sealing surface (8) and the third sealing surface (12) together form a seal.

4. The multi-stage sealing structure for a valve plate closing mechanism according to claim 3, characterized in that: The spherical arc surface of the valve plate a (1) forms a linear seal with the second sealing surface (8) and the third sealing surface (12).

5. The multi-stage sealing structure for a valve plate closing mechanism according to claim 3, characterized in that: The third sealing surface (12) is a metal sealing surface.

6. The multi-stage sealing structure for a valve plate closing mechanism according to claim 3, characterized in that: An annular protrusion (11) is provided on the first sealing surface (7).

7. The multi-stage sealing structure for a valve plate closing mechanism according to claim 1, characterized in that: The composite sealing ring (5) is provided with a groove, and a spring ring (6) which is generally U-shaped is arranged in the groove.

8. The multi-stage sealing structure for a valve plate closing mechanism according to claim 1, characterized in that: An annular release groove (10) is formed on the side of the composite sealing ring (5) that contacts the valve seat a (2).

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