Sealing unit of recoverable composite rubber sleeve

Abstract

The sealing unit of the recoverable composite rubber sleeve comprises a middle rubber sleeve, end face rubber sleeves and outburst prevention supports are sequentially and symmetrically arranged at the two ends of the middle rubber sleeve in the direction away from the middle rubber sleeve, metal check rings are connected between the middle rubber sleeve and the end face rubber sleeves, and isolating rings are connected between the end face rubber sleeves and the outburst prevention supports. According to the recoverable composite rubber sleeve sealing unit, the two ends of the middle rubber sleeve are connected with the metal check rings and the end face rubber sleeves to form a main pressure-bearing sealing rubber sleeve mechanism, the isolating rings on the two sides of the middle rubber sleeve play roles in auxiliary sealing and isolation of stratum media, and the outburst-preventing supporting mechanism on the outermost side plays a role in supporting the outburst-preventing supporting mechanism. The rubber sleeve sealing mechanism is supported in a completely closed and recoverable mode, so that it is guaranteed that the sealing rubber sleeve does not leak in the ultra-high-temperature and high-pressure sealing process, the sealing requirement of the ultra-high-temperature and high-pressure well in the embodiment under the environment that the high temperature is 232 DEG C and the high pressure is 105 MPa is met, and the pressure-bearing sealing portion does not deform or lose sealing.

Description

Technical Field

[0001] The utility model belongs to the technical field of petroleum and natural gas downhole testing tools and relates to a sealing unit of a recoverable composite rubber cartridge. Background Art

[0002] The rubber cartridge sealing unit is the key mechanism of the packer, which is mainly composed of sealing elements and various anti-outburst components to prevent the shoulder of the sealing element from protruding. The sealing performance of the rubber cartridge is crucial in downhole testing operations. The main rubber seal on the pipe string that affects the operating pressure and temperature is the rubber cartridge unit on the packer. At present, on the recoverable packer, the performance of the rubber cartridge with a working pressure of 204°C and 105MPa is relatively stable; but with the increase in drilling depth, the operating temperature and pressure are also getting higher and higher. 204°C and 105MPa can no longer meet many operating requirements. An ultra-high temperature and high pressure rubber cartridge sealing unit is urgently needed to meet the current ultra-high temperature and high pressure testing operations. At present, most ultra-high temperature and high pressure rubber cartridge sealing units on the market have problems such as a small applicable temperature range, weak medium resistance, short working life, low reliability, and easy deformation and loss of sealing at the pressure-bearing sealing part. Utility Model Content

[0003] The utility model aims to provide a sealing unit of a recyclable composite rubber cartridge, which solves the technical problem of deformation and sealing failure of the pressure-bearing sealing part of the existing rubber cartridge unit in ultra-high temperature and high pressure operation in the prior art.

[0004] The technical solution adopted by the utility model is that the sealing unit of the recyclable composite rubber cylinder includes a middle rubber cylinder, and end rubber cylinders and anti-burst supports are symmetrically arranged at both ends of the middle rubber cylinder in a direction away from the middle rubber cylinder, a metal retaining ring is connected between the middle rubber cylinder and the end rubber cylinder, and an isolation ring is connected between the end rubber cylinder and the anti-burst support.

[0005] The utility model is also characterized in that:

[0006] The inner wall of the middle rubber cylinder is provided with a V-shaped arc groove structure, and a V-shaped spring is installed in the V-shaped arc groove structure.

[0007] The outer wall of the middle rubber cylinder is provided with a V-shaped arc groove structure.

[0008] The end face rubber sleeve and the isolating ring are sleeved with a supporting ring near the edge of the inner hole.

[0009] The anti-outburst support comprises a butterfly spring, the butterfly spring is circumferentially wrapped with a metal wire mesh, and rubber is vulcanized on the surface of the metal wire mesh.

[0010] An O-ring is sleeved on one end of the anti-protrusion support away from the isolating ring and close to the edge of the inner hole.

[0011] The beneficial effects of the utility model are:

[0012] The utility model discloses a recyclable composite rubber tube sealing unit, which forms a main pressure-bearing sealing rubber tube mechanism by connecting metal retaining rings and end rubber tubes at both ends of an intermediate rubber tube. The isolation rings on both sides thereof play a role of auxiliary sealing and isolating the formation medium. The outermost anti-blowout support mechanism forms a completely closed and recyclable support for the rubber tube sealing mechanism to ensure that the sealing rubber tube does not leak during ultra-high temperature and high pressure sealing, and meets the sealing requirements of the ultra-high temperature and high pressure well in the present embodiment under the high temperature of 232°C and the high pressure of 105MPa. No deformation or loss of sealing occurs at the pressure-bearing sealing part. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a structural schematic diagram of the sealing unit of the recyclable composite rubber cartridge of the utility model;

[0014] Figure 2 It is a schematic diagram of the anti-burst support structure in the sealing unit of the recyclable composite rubber cartridge of the utility model;

[0015] Figure 3 The utility model is a schematic structural diagram of the sealing unit of the recyclable composite rubber cartridge after being set.

[0016] In the figure, 1. O-ring, 2. anti-burst support, 3. isolation ring, 4. support ring, 5. end face rubber cylinder, 6. metal retaining ring, 7. middle rubber cylinder, 8. V-shaped spring, 9. butterfly spring, 10. metal wire mesh. DETAILED DESCRIPTION

[0017] The utility model is described in detail below with reference to the accompanying drawings and specific implementation modes.

[0018] Example 1

[0019] like Figure 1 As shown, the utility model provides a sealing unit of a recyclable composite rubber cylinder, comprising an intermediate rubber cylinder 7, at both ends of which are symmetrically arranged in sequence along a direction away from the intermediate rubber cylinder 7, end rubber cylinders 5 and anti-outburst supports 2, a metal retaining ring 6 is connected between the intermediate rubber cylinder 7 and the end rubber cylinder 5, and an isolation ring 3 is connected between the end rubber cylinder 5 and the anti-outburst support 2. In the above structure, the outer cone of the isolation ring 3 contacts the inner cone of the anti-outburst support 2; the inner cone of the isolation ring 3 contacts the end rubber cylinder 5 and the support ring 4 respectively; the outer cone of one end of the support ring 4 contacts the inner cone of the isolation ring 3, and the outer cone of the other end contacts the inner cone groove of the hole of the end rubber cylinder 5; the outer cone of the end rubber cylinder 5 contacts the isolation ring 3, and the inner cone of the hole contacts the support ring 4; the other end contacts the end face of the metal retaining ring 6; the metal retaining ring 6 is arranged between the end rubber cylinder 5 and the intermediate rubber cylinder 7, and the two end faces contact the intermediate rubber cylinder 7 and the end rubber cylinder 5 respectively.

[0020] In the utility model, the metal retaining ring 6 is arranged between the end rubber cylinder 5 and the middle rubber cylinder 7, which can effectively transmit the sealing force applied to the rubber cylinder mechanism, improve the sealing ability of the rubber cylinder, and also prevent the rubber from leaking from the inner hole of the middle rubber cylinder sequence 7 when subjected to high pressure difference, resulting in a decrease in sealing ability.

[0021] Example 2

[0022] On the basis of Embodiment 1, a V-shaped circular arc groove structure is provided on the inner wall of the middle rubber cylinder 7, and a V-shaped spring 8 is installed in the V-shaped circular arc groove structure.

[0023] The inner hole of the middle rubber cylinder 7 is provided with two V-shaped arc groove structures, which can effectively reduce the minimum complete sealing force of the rubber cylinder. The V-shaped spring 8 embedded in the V-shaped arc groove provides a reaction force to the middle rubber cylinder 7 after being compressed by the axial sealing force, thereby increasing the contact stress between the middle rubber cylinder 7 and the inner wall of the casing, thereby enhancing the sealing ability.

[0024] The outer wall of the middle rubber cylinder 7 is provided with a V-shaped arc groove structure.

[0025] A V-shaped arc groove structure is arranged on the outer circumferential surface of the middle rubber cylinder 7. After the rubber cylinder is compressed by the axial force, there will be two sealing contact surfaces with the inner wall of the sleeve, which increases the contact friction stress between the middle rubber cylinder 7 and the inner wall of the sleeve and improves the sealing performance;

[0026] The end face rubber sleeve 5 and the isolating ring 3 are sleeved with a supporting ring 4 near the edge of the inner hole.

[0027] The support ring 4 is made of copper alloy or PEEK high molecular polymer material.

[0028] The support ring 4 is made of copper alloy or PEEK polymer material, and is arranged before the isolation ring 3 and the end face rubber tube 5 to provide support for the high temperature and high pressure deformation of the isolation ring 3 and the end face rubber tube 5, so that the setting force can be efficiently transmitted. At the same time, it can prevent the rubber material of the end face rubber tube 5 from leaking from the inner hole, resulting in a decrease in sealing ability.

[0029] The anti-protrusion support 2 includes a butterfly spring 9, which is circumferentially wrapped with a metal wire mesh 10, and the surface of the metal wire mesh 10 is vulcanized with rubber.

[0030] The internal structure of the anti-burst support 2 is as follows Figure 2As shown, it includes a butterfly spring 9 and a supporting metal wire mesh 10. The butterfly spring 9 is used as a skeleton to cover the supporting metal wire mesh 10. After molding, a layer of rubber is vulcanized on the outer surface to fill the surface gaps and shape it. The anti-outburst support 2 is arranged on both sides of the isolation ring, and the end face is in contact with the rubber tube shoe. The shoulder anti-outburst structure is deformed and stretched open and squeezed on the inner wall of the casing under the action of the axial sealing force, and withstands the shear force under the action of high temperature and high pressure to prevent the rubber tube from protruding into the annular gap between the rubber tube shoe and the casing after being stressed. When the rubber tube is unsealed, the butterfly spring 9 arranged inside the anti-outburst support 2 rebounds under the action of elastic force, driving the metal wire mesh to retract, making it convenient for the rubber tube to be recovered.

[0031] An O-ring 1 is sleeved on one end of the anti-protrusion support 2 away from the isolation ring 3 and close to the edge of the inner hole.

[0032] The O-ring 1 is arranged on the end surface of the anti-protrusion support 2 and is sleeved on the outer circle of the rubber sleeve mandrel to assist in preventing leakage between the sealing gap between the inner hole of the rubber sleeve and the outer surface of the mandrel.

[0033] The isolation ring 3 is made of high molecular polymer material.

[0034] The isolation ring 3 is made of a high molecular polymer with high temperature resistance and excellent medium resistance, such as PTFE. It has excellent medium resistance at high temperatures. It is arranged between the anti-outburst support 2 and the end face rubber tube 5 to prevent the metal wire mesh in the anti-outburst support 2 from directly contacting the rubber and squeezing the end face rubber tube 5. Under the action of axial force at high temperatures, the isolation ring softens and deforms and squeezes to contact the inner wall of the sleeve, playing an auxiliary sealing and isolating medium, especially preventing gas from penetrating into the rubber and causing medium corrosion and gas swelling damage to the rubber tube.

[0035] The end rubber cylinder 5 and the middle rubber cylinder 7 are both made of pure rubber, and the rubber material of the end rubber cylinder 5 is 5-10 Shore A harder than that of the middle rubber cylinder 7. The lower hardness of the middle rubber cylinder 7 than the end rubber cylinder 5 is more conducive to the transmission of the setting force, so that the deformation of the middle rubber cylinder 7 is more sufficient, the contact stress with the inner wall of the casing is greater, and the sealing effect is better.

[0036] Example 3

[0037] The inner diameters of the O-ring 1, the anti-burst support 2, the isolation ring 3, the support ring 4, the end face rubber cylinder 5, the metal retaining ring 6, the middle rubber cylinder 7, the V-shaped spring 8, the butterfly spring 9 and the metal wire mesh 10 are the same, which is convenient for sleeve connection with the core shaft and has good sealing performance.

[0038] Working process of the recyclable compression rubber cylinder sealing unit of the utility model: The utility model is applied to the rubber cylinder mandrel of the recyclable packer. After the rubber cylinder sealing unit is compressed and sealed by axial force, the gap with the inner wall of the casing is reduced in sequence from O-ring 1 → anti-bumping support 2 → isolation ring 3 → support ring 4 → end rubber cylinder 5 → metal retaining ring 6 → middle rubber cylinder 7. In particular, the anti-bumping support 2 is completely in contact with the inner wall of the casing after sealing. The metal wire mesh 10 and butterfly spring 9 inside it provide strength support, forming a strong shoulder anti-bumping structure for the end rubber cylinder 5 and the middle rubber cylinder 7. The support ring 4 bears the inner hole pressure load to protect the end rubber cylinder 5 from puncture and leakage under high temperature and high pressure; the recyclable compression rubber cylinder sealing unit in one embodiment of the utility model meets the sealing requirements of high temperature 232℃ and high pressure 105MPa in high temperature and high pressure wells, and there is no deformation or loss of sealing in the pressure-bearing sealing part.

[0039] The working principle of the sealing unit of the recyclable compression rubber cartridge of the utility model is as follows:

[0040] like Figure 3 As shown, with the application of the sealing force, the O-ring 1, the anti-burst support 2, the isolation ring 3, the end face rubber cylinder 5, and the middle rubber cylinder 7 are compressed and deformed. The butterfly spring 9 inside the anti-burst support 2 is stretched and deformed accordingly. The isolation ring 3 is deformed by compression, and the outer diameter increases, and finally forms a closed protection on the inner wall of the casing for the end face rubber cylinder 5 and the middle rubber cylinder 7. When the support ring 4 is set, it can effectively transmit the sealing force to the end face rubber cylinder 5, and provide support for the deformation of the isolation ring 3 and the end face rubber cylinder 5. After setting, the support ring 4 will produce a slight deformation, and the inner diameter will be the same as the outer diameter of the mandrel of the packer, which can prevent the end face rubber cylinder 5 and the middle rubber cylinder 7 from leaking from the matching gap between the mandrel and the rubber cylinder sealing unit under high temperature and high pressure. At the same time, when the rubber cylinder unit is sealed, the support ring 4 bears the inner hole pressure load. After the middle rubber cylinder 7 is fully deformed, the V-shaped spring 8 arranged in the inner hole groove of the middle rubber cylinder 7 is also deformed by force, generating elastic deformation force, providing support force for the rubber cylinder seal. When the rubber cylinder is unsealed, the elastic force is released, accelerating the deformation recovery of the rubber cylinder, which is beneficial to the recovery of the rubber cylinder.

Claims

1. The sealing unit of the recyclable composite rubber cartridge is characterized in that: The invention comprises a middle rubber cylinder (7), end rubber cylinders (5) and anti-outburst supports (2) are symmetrically arranged in sequence at both ends of the middle rubber cylinder (7) in a direction away from the middle rubber cylinder (7), a metal retaining ring (6) is connected between the middle rubber cylinder (7) and the end rubber cylinder (5), and an isolation ring (3) is connected between the end rubber cylinder (5) and the anti-outburst support (2).

2. The sealing unit of the recyclable composite rubber cartridge according to claim 1, characterized in that: The inner wall of the middle rubber cylinder (7) is provided with a V-shaped circular arc groove structure, and a V-shaped spring (8) is installed in the V-shaped circular arc groove structure.

3. The sealing unit of the recyclable composite rubber cartridge according to claim 1, characterized in that: The outer wall of the middle rubber cylinder (7) is provided with a V-shaped circular arc groove structure.

4. The sealing unit of the recyclable composite rubber cartridge according to claim 1, characterized in that: The end face rubber sleeve (5) and the isolation ring (3) are sleeved with a support ring (4) near the edge of the inner hole.

5. The sealing unit of the recyclable composite rubber cartridge according to claim 1, characterized in that: The anti-protrusion support (2) comprises a butterfly spring (9), the butterfly spring (9) is circumferentially wrapped with a metal wire mesh (10), and the surface of the metal wire mesh (10) is vulcanized with rubber.

6. The sealing unit of the recyclable composite rubber cartridge according to claim 5, characterized in that: An O-ring (1) is sleeved on one end of the anti-protrusion support (2) away from the isolation ring (3) near the edge of the inner hole.

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