Sealing inspection method for joints and oil pipes

Abstract

The present invention provides a seal-testing joint and a method for testing the seal of an oil pipe. The seal-testing joint comprises: a joint body having a flow chamber, an inlet communicating with the flow chamber, and an outlet communicating with the flow chamber; a first threaded section connected to the joint body, the first threaded section being disposed on the outer wall of the joint body and located at one end where the outlet is located, the joint body being connected to a component to be tested via the first threaded section; and a first operating portion disposed on the joint body, wherein the first operating portion is rotated to install the joint body to the component to be tested. The technical solution of the present invention can smoothly perform pressure testing and seal-testing on oil pipes in pumping wells.

Description

Technical Field

[0001] The present invention relates to the technical field of sealing inspection, in particular to a sealing inspection joint and an oil pipe sealing inspection method. Background Art

[0002] During mechanical oil production in pumping wells, tubing damage can easily occur due to friction between the sucker rod and the tubing, or due to corrosion from gas and liquid inside the wellbore. The current method for verifying tubing seals involves using a pump truck to inject liquid into the tubing through the wellhead nozzle sleeve to pressurize it. Typically, the pressure is increased to 5 to 8 MPa, then the pump is stopped and the pressure in the tubing is observed to drop. A rapid drop in pressure indicates a leak in the tubing; otherwise, the seal is tight. Both the production valve and the back-pressure valve are tightly connected to the wellhead nozzle sleeve. During this process, the pressure inside the wellhead nozzle sleeve and at the back-pressure valve are the same as the pressure inside the tubing. However, the back-pressure valve's pressure tolerance is generally below 2.5 MPa. Therefore, when using this method to pressure-test and seal the tubing, the back-pressure valve's low pressure tolerance can result in the pressure at the back-pressure valve exceeding its operating pressure. Therefore, how to smoothly carry out pressure testing and sealing of the oil pipe of the pumping well is a problem that needs to be solved urgently. Summary of the Invention

[0003] The main purpose of the present invention is to provide a sealing test joint and an oil pipe sealing test method, which can smoothly perform pressure testing and sealing test on the oil pipe of an oil pumping well.

[0004] In order to achieve the above-mentioned purpose, according to one aspect of the present invention, a sealing inspection joint is provided, comprising: a joint body, the joint body having a flow chamber, an inlet connected to the flow chamber, and an outlet connected to the flow chamber; a first threaded section, connected to the joint body, the first threaded section being arranged on the outer wall surface of the joint body and located at the end where the outlet is located, the joint body being connected to the component to be inspected through the first threaded section; a first operating part, arranged on the joint body, and screwing the first operating part can install the joint body to the component to be inspected.

[0005] Furthermore, the seal verification joint also includes a second threaded section arranged on the inner wall surface of the flow chamber, the second threaded section is located at the end where the inlet is located, and the joint body is connected to the fluid conveying equipment through the second threaded section.

[0006] Furthermore, the first operating portion is located between the first thread segment and the second thread segment.

[0007] Furthermore, the sealing inspection joint also includes a sealing structure connected to the joint body, the sealing structure is movably arranged relative to the joint body, and the sealing structure is used to seal the gap between the joint body and the component to be inspected.

[0008] Furthermore, the sealing structure includes a sealing body arranged on the outer periphery of the joint body, at least part of the inner wall surface of the sealing body is provided with an internal thread, at least part of the outer wall surface of the joint body is provided with an external thread adapted to the internal thread, and the sealing body and the joint body are threadedly matched.

[0009] Furthermore, the sealing structure also includes a third threaded segment connected to the sealing body, the third threaded segment is arranged on at least part of the outer wall surface of the sealing body, and the sealing body is threadedly connected to the component to be checked through the third threaded segment; or, the sealing structure also includes a stopper connected to the sealing body; or, the sealing structure also includes a second operating part connected to the sealing body, and under the action of external force, the second operating part drives the sealing body to move relative to the joint body; or, the sealing structure also includes a third threaded segment, a stopper and a second operating part, and along the direction of fluid flow, the second operating part, the stopper and the third threaded segment are sequentially arranged on the sealing body.

[0010] Furthermore, the sealing joint also includes a sealing structure arranged on the first threaded section, which is used to seal the connection between the first threaded section and the component to be checked; or, the first operating part includes an operating block arranged on at least a portion of the outer wall surface of the joint body, and the operating block has at least two outer wall surfaces arranged at an angle.

[0011] According to another aspect of the present invention, a method for verifying the sealing of an oil pipe is provided. The method adopts the above-mentioned sealing verification joint to perform sealing verification, and the method comprises: step S10: installing the sealing verification joint to the oil pipe to be verified; step S20: connecting a fluid conveying device to the sealing verification joint; step S30: conveying the fluid through the sealing verification joint into the oil pipe to be verified by the fluid conveying device, so that the pressure in the oil pipe to be verified increases to a predetermined value; step S40: stopping the fluid conveying, observing the pressure drop in the oil pipe to be verified, and judging whether the pressure drop in the oil pipe to be verified exceeds 30% of the predetermined value within 3 to 5 minutes; if so, the oil pipe to be verified is not sealed; if not, the oil pipe to be verified is sealed.

[0012] Furthermore, the oil pipe to be inspected and sealed is connected to the wellhead oil nozzle sleeve, and a production valve is provided at one end of the oil pipe to be inspected and sealed close to the wellhead oil nozzle sleeve. The wellhead oil nozzle sleeve has a cavity, a first opening connected to the cavity, a second opening connected to the cavity, and a third opening connected to the cavity. The oil pipe to be inspected and sealed is arranged at the first opening, the wellhead oil nozzle sleeve is connected to the back pressure valve, the back pressure valve is arranged at the second opening, the wellhead oil nozzle sleeve is connected to the wellhead oil nozzle sleeve thread plug, and the wellhead oil nozzle sleeve thread plug is arranged at the third opening; before step S10, the oil pipe sealing method also includes: step S05: closing the production valve and the back pressure valve, emptying the wellhead oil nozzle sleeve, removing the wellhead oil nozzle sleeve thread plug, and opening the third opening.

[0013] Further, step S10 includes: step S11: connecting the first threaded section to at least part of the inner wall surface of the wellhead nozzle sleeve so that the flow cavity of the joint body is connected to the first opening; step S12: connecting the sealing structure to at least part of the inner wall surface of the wellhead nozzle sleeve, and using the sealing structure to block the third opening.

[0014] Furthermore, between step S20 and step S30, the oil pipe sealing inspection method further includes: step S25: opening the production valve to connect the flow cavity of the joint body with the inner cavity of the oil pipe to be inspected.

[0015] By applying the technical solution of the present invention, the joint body is connected to the component to be tested through the first threaded section, the flow chamber is connected to the inner cavity of the component to be tested through the outlet, the fluid is introduced into the flow chamber through the inlet, and the fluid enters the inner cavity of the component to be tested through the outlet, so that the pressure in the component to be tested is increased to a predetermined value. After that, whether the component to be tested is sealed is determined based on the pressure change in the component to be tested, thereby completing the pressure test and sealing operation of the component to be tested. When the sealing test joint of the present application is used to perform a pressure test and sealing test on the oil pipe of the pumping well, the joint body is threadedly connected to at least a portion of the inner wall surface of the wellhead nozzle sleeve through the first threaded section or is directly threadedly connected to at least a portion of the inner wall surface of the oil pipe to be tested, so that the flow chamber is connected to the inner cavity of the oil pipe to be tested. In this way, fluid can be introduced into the flow chamber through the inlet of the joint body, and the fluid can enter the inner cavity of the oil pipe to be tested through the outlet, so that the pressure in the oil pipe to be tested is increased to a predetermined value, and it can be further determined whether the oil pipe to be tested is sealed. In the process of performing a pressure test and sealing test on the oil pipe of the pumping well using the sealing test joint of the present application, the fluid can directly enter the inner cavity of the oil pipe to be tested through the flow chamber without entering the cavity of the wellhead nozzle sleeve. In this way, the pressure in the wellhead nozzle sleeve and the pressure at the back pressure valve will not increase, thereby avoiding the problem that the pressure at the back pressure valve exceeds the working pressure of the back pressure valve, and the oil pipe of the pumping well can be pressure tested and sealed smoothly. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The accompanying drawings, which constitute part of this application, are intended to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are intended to explain the present invention and do not constitute an undue limitation of the present invention. In the accompanying drawings:

[0017] Figure 1 A schematic structural diagram of an embodiment of a seal verification joint according to the present invention is shown;

[0018] Figure 2 Shown Figure 1 A schematic diagram of the structure of the connection between the sealing test joint and the wellhead nozzle sleeve;

[0019] Figure 3 A flow chart showing an embodiment of the oil pipe seal verification method according to the present invention; and

[0020] Figure 4 Shown Figure 3 Specific flow chart of the oil pipeline sealing inspection method.

[0021] The above drawings include the following reference numerals:

[0022] 10. Connector body; 11. Flow chamber; 111. First chamber section; 112. Second chamber section; 12. Inlet; 13. Outlet; 14. External thread; 20. First threaded section; 40. First operating part; 41. Operating block; 50. Second threaded section; 60. Sealing structure; 61. Sealing body; 62. Third threaded section; 63. Stopper; 64. Second operating part; 70. Sealing structure; 80. Wellhead nozzle sleeve; 81. Cavity; 82. First opening; 83. Second opening. DETAILED DESCRIPTION

[0023] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in this application can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0024] It should be noted that, unless otherwise specified, all technical and scientific terms used in this application have the same meaning as commonly understood by ordinary technicians in the technical field to which this application belongs.

[0025] In the present invention, unless otherwise specified, the directional words used, such as "up, down, top, bottom", usually refer to the directions shown in the drawings, or to the components themselves in the vertical, perpendicular or gravity direction; similarly, for ease of understanding and description, "inside and outside" refer to the inside and outside relative to the outline of each component itself, but the above directional words are not used to limit the present invention.

[0026] In the present invention and the embodiments of the present invention, the oil pipe is connected to the wellhead nozzle sleeve, and a production valve is provided at one end of the oil pipe close to the wellhead nozzle sleeve. The wellhead nozzle sleeve has a cavity, a first opening connected to the cavity, a second opening connected to the cavity, and a third opening connected to the cavity. The oil pipe is arranged at the first opening, the wellhead nozzle sleeve is connected to the back pressure valve, the back pressure valve is arranged at the second opening, the wellhead nozzle sleeve is connected to the wellhead nozzle sleeve thread plug, and the wellhead nozzle sleeve thread plug is arranged at the third opening.

[0027] In view of the problem in the prior art that, during the pressure test and sealing inspection of the oil pipe of the pumping well, the pressure in the cavity of the wellhead oil nozzle sleeve and the pressure at the back pressure valve are the same as the pressure in the oil pipe, resulting in the pressure at the back pressure valve exceeding the working pressure of the back pressure valve, the present invention and the embodiments of the present invention provide a sealing inspection joint and an oil pipe sealing inspection method.

[0028] It should be noted that, in the embodiment of the present invention, the component to be verified is the oil pipe of the pumping well or the wellhead nozzle sleeve connected to the oil pipe of the pumping well.

[0029] like Figure 1 and Figure 2 As shown, in an embodiment of the present invention, the sealing joint includes a joint body 10, a first threaded section 20 and a first operating part 40, the joint body 10 has a flow chamber 11, an inlet 12 connected to the flow chamber 11 and an outlet 13 connected to the flow chamber 11; the first threaded section 20 is connected to the joint body 10, the first threaded section 20 is arranged on the outer wall surface of the joint body 10 and is located at the end where the outlet 13 is located, the joint body 10 is connected to the component to be checked through the first threaded section 20; the first operating part 40 is arranged on the joint body 10, and screwing the first operating part 40 can install the joint body 10 to the component to be checked.

[0030] In the above arrangement, the connector body 10 is connected to the component to be checked through the first threaded section 20, the flow chamber 11 is connected to the inner cavity of the component to be checked through the outlet 13, and the fluid is introduced into the flow chamber 11 through the inlet 12. The fluid enters the inner cavity of the component to be checked through the outlet 13, so that the pressure in the component to be checked increases to a predetermined value. After that, whether the component to be checked is sealed is determined based on the pressure change in the component to be checked, thereby completing the pressure test and sealing operation of the component to be checked.

[0031] When the sealing test joint of the present application is used to perform pressure testing and sealing on the oil pipe of the pumping well, the joint body 10 is threadedly connected to at least part of the inner wall surface of the wellhead nozzle sleeve through the first threaded section 20 or is directly threadedly connected to at least part of the inner wall surface of the oil pipe to be tested, so that the flow chamber 11 is connected to the inner cavity of the oil pipe to be tested. In this way, fluid can be introduced into the flow chamber 11 through the inlet 12 of the joint body 10, and the fluid can enter the inner cavity of the oil pipe to be tested through the outlet 13, so that the pressure in the oil pipe to be tested is increased to a predetermined value, and it can be further determined whether the oil pipe to be tested is sealed; compared with squeezing liquid into the oil pipe through the wellhead nozzle sleeve to test Pressure is applied to the oil pipe by pressure testing, so that the pressure in the cavity of the wellhead oil nozzle sleeve and the pressure at the back-pressure valve are the same as the pressure in the oil pipe, resulting in the pressure at the back-pressure valve exceeding the working pressure of the back-pressure valve. In terms of technology, in the process of pressure testing and sealing the oil pipe of the pumping well using the sealing joint of the present application, the fluid can directly enter the inner cavity of the oil pipe to be tested and sealed through the flow cavity 11 without entering the cavity of the wellhead oil nozzle sleeve. In this way, the pressure in the wellhead oil nozzle sleeve and the pressure at the back-pressure valve will not increase, thereby avoiding the problem that the pressure at the back-pressure valve exceeds the working pressure of the back-pressure valve, and the oil pipe of the pumping well can be pressure tested and sealed smoothly.

[0032] In addition, the first operating portion 40 is provided to facilitate installation of the connector body 10 to the component to be checked; specifically, by screwing the first operating portion 40, the first threaded segment 20 can be threadedly engaged with the component to be checked, and finally the connector body 10 can be threadedly connected to the component to be installed.

[0033] Preferably, if Figure 1 and Figure 2 As shown, in the embodiment of the present invention, the first thread segment 20 is a thread provided on the outer wall surface of the connector body 10. The first thread segment 20 is integrally formed with the connector body 10, and the connector body 10 is threadedly connected to the component to be verified via the first thread segment 20. Of course, in alternative embodiments not shown in the drawings of this application, the first thread segment 20 can also be provided separately from the connector body 10 and connected thereto according to actual needs, wherein the first thread segment 20 has external threads to facilitate connection with the component to be verified.

[0034] like Figure 1 and Figure 2 As shown, in an embodiment of the present invention, the seal verification joint further includes a sealing structure 70 disposed on the first threaded segment 20, and the sealing structure 70 is used to seal the connection between the first threaded segment 20 and the component to be verified. The sealing structure 70 can seal the first threaded segment 20 and the component to be verified, thereby preventing fluid from entering the inner cavity of the wellhead nozzle sleeve through the connection between the first threaded segment 20 and the component to be verified, thereby increasing the pressure in the wellhead nozzle sleeve and at the back pressure valve, resulting in the pressure at the back pressure valve exceeding the working pressure of the back pressure valve. The provision of the sealing structure 70 can also make the connection between the first threaded segment 20 and the component to be verified more secure.

[0035] Preferably, the sealing structure 70 is located at an end of the first threaded section 20 away from the outlet 13 to ensure sealing performance.

[0036] Preferably, the sealing structure 70 is a gasket. Preferably, the sealing structure 70 is a metal gasket.

[0037] like Figure 1 and Figure 2 As shown, in an embodiment of the present invention, the first operating portion 40 includes an operating block 41 disposed on at least a portion of the outer wall of the connector body 10. The operating block 41 has at least two outer wall surfaces arranged at an angle. By applying an external force to the operating block 41, that is, by twisting the operating block 41, the operating block 41 can cause the connector body 10 to rotate about its own axis, thereby threading the first threaded segment 20 and the component to be verified, thereby achieving the purpose of threaded connection between the connector body 10 and the component to be verified. The provision of the operating block 41 facilitates the installation of the connector body 10 using tools such as a pipe wrench or a wrench.

[0038] In addition, at least two outer wall surfaces of the operating block 41 are arranged at an angle, so that external force can be easily applied to the operating block 41 to facilitate screwing of the operating block 41 .

[0039] Preferably, if Figure 1 and Figure 2 As shown, in the embodiment of the present invention, the operating block 41 is a polygonal block that is inserted into the connector body 10. This arrangement allows the operating block 41 to be conveniently and easily screwed, causing the operating block 41 to rotate the connector body 10, thereby facilitating the threaded connection between the connector body 10 and the component to be checked.

[0040] Preferably, the operating block 41 is integrally formed with the connector body 10. This arrangement ensures a secure connection between the operating block 41 and the connector body 10, allowing accurate and stable rotation of the connector body 10 via the operating block 41. Of course, in alternative embodiments, the operating block 41 can be separately connected to the connector body 10, depending on actual needs.

[0041] like Figure 1 and Figure 2 As shown, in an embodiment of the present invention, the sealing joint further includes a second threaded section 50 arranged on the inner wall surface of the flow chamber 11, the second threaded section 50 is located at the end where the inlet 12 is located, and the joint body 10 is connected to the fluid conveying equipment through the second threaded section 50.

[0042] In the above arrangement, the connector body 10 is connected to the fluid conveying device through the second threaded section 50, and the inner cavity of the fluid conveying device is connected to the flow cavity 11 through the inlet 12 of the connector body 10. The fluid is conveyed into the flow cavity 11 through the fluid conveying device, and the fluid enters the inner cavity of the component to be tested through the outlet 13, and increases the pressure in the component to be tested to a predetermined value, thereby achieving the purpose of pressure testing and sealing the component to be tested.

[0043] Preferably, the fluid delivery device is a pump truck, and the second threaded section 50 matches the oil pipe thread of the pump truck quick connector.

[0044] Preferably, in the embodiment of the present invention, the second thread segment 50 is a threaded section provided on the inner wall surface of the flow chamber 11 of the connector body 10. The second thread segment 50 is integrally formed with the connector body 10, and the connector body 10 is threadedly connected to the fluid conveying device via the second thread segment 50. Of course, in alternative embodiments not shown in the drawings of this application, the second thread segment 50 can also be provided separately from the connector body 10 and connected thereto according to actual needs, wherein the second thread segment 50 has internal threads to facilitate connection with the fluid conveying device.

[0045] Preferably, if Figure 1 and Figure 2As shown, in an embodiment of the present invention, the flow chamber 11 runs through the entire connector body 10 to ensure the flow of high-pressure liquid and to isolate the passage between the wellhead production valve and the back-pressure valve. The flow chamber 11 includes a first cavity section 111 corresponding to the second threaded section 50 and a second cavity section 112 connected to the first cavity section 111. The inlet 12, the first cavity section 111, the second cavity section 112 and the outlet 13 are arranged in sequence, wherein the radial dimension of the inner wall surface of the first cavity section 111 is greater than the radial dimension of the inner wall surface of the second cavity section 112. Such an arrangement enables the connector body 10 to be connected to the fluid conveying equipment through the second threaded section 50, and can also ensure the flow rate of the fluid in the flow chamber 11.

[0046] Preferably, the second cavity section 112 is a through hole with a diameter of φ20.

[0047] like Figure 1 and Figure 2 As shown, in this embodiment of the present invention, the first operating portion 40 is located between the first thread segment 20 and the second thread segment 50. This arrangement allows the first thread segment 20 to be easily connected to the component to be verified, and the second thread segment 50 to be easily connected to the fluid delivery device. At the same time, the first thread segment 20 can be connected to the component to be verified by simply twisting the first operating portion 40. This arrangement is reasonable and convenient.

[0048] Preferably, in an embodiment of the present invention, the operating block 41 is located at the end where the inlet 12 is located. When the connector body 10 is threadedly engaged with the component to be verified via the first threaded segment 20, the operating block 41 is located outside the component to be verified. With this arrangement, the connector body 10 can be easily rotated by applying an external force to the operating block 41, thereby achieving a threaded connection between the connector body 10 and the component to be verified.

[0049] like Figure 1 and Figure 2 As shown, in an embodiment of the present invention, the sealing joint further includes a sealing structure 60 connected to the joint body 10. The sealing structure 60 is movably arranged relative to the joint body 10. The sealing structure 60 is used to seal the gap between the joint body 10 and the component to be checked.

[0050] By moving the sealing structure 60 relative to the joint body 10, the sealing structure 60 gradually blocks the gap between the joint body 10 and the component to be checked. This arrangement can prevent the component to be checked from being connected to the external environment, and prevent material exchange from occurring between the component to be checked and the external environment (for example, when using the sealing joint of the present application to perform pressure testing and sealing on the oil pipe of the pumping well, the back pressure valve needs to be closed. The sealing effect of the sealing structure 60 on the gap between the joint body 10 and the component to be checked can avoid the problem of oil and gas leaking to the outside through the gap between the joint body 10 and the component to be checked when the back pressure valve is not closed tightly). It can also make the joint body 10 and the component to be checked more stably connected, so that the component to be checked can stably support and fix the joint body 10 through the sealing structure 60.

[0051] like Figure 1 and Figure 2 As shown, in an embodiment of the present invention, the sealing structure 60 includes a sealing body 61 arranged on the outer periphery of the connector body 10, and an internal thread is provided on at least a portion of the inner wall surface of the sealing body 61, and an external thread 14 adapted to the internal thread is provided on at least a portion of the outer wall surface of the connector body 10, and the sealing body 61 is threadedly matched with the connector body 10.

[0052] In the above-mentioned setting, the sealing body 61 is arranged on the outer periphery of the joint body 10 and is threadedly engaged with the joint body 10. Through the threaded engagement between the sealing body 61 and the joint body 10, the rotational motion can be converted into linear motion, so that the sealing body 61 is movably arranged relative to the joint body 10, and then through the movement of the sealing body 61 relative to the joint body 10, the purpose of using the sealing body 61 to block the gap between the joint body 10 and the component to be checked can be achieved.

[0053] like Figure 1 and Figure 2 As shown, in an embodiment of the present invention, the sealing structure 60 also includes a third threaded segment 62 connected to the sealing body 61. The third threaded segment 62 is arranged on at least a portion of the outer wall surface of the sealing body 61. The sealing body 61 is threadedly connected to the component to be checked through the third threaded segment 62.

[0054] In the above arrangement, the plugging body 61, through the internal threads on its inner wall, threadably engages with the joint body 10 and is movable relative to the joint body 10. During its movement relative to the joint body 10, the plugging body 61 is threadedly connected to the component to be verified via the third threaded segment 62, thereby sealing the gap between the joint body 10 and the component to be verified. The plugging body 61 supports the entire joint body 10 and seals the third opening of the wellhead nozzle sleeve, preventing potential oil and gas leakage due to a loose backpressure valve.

[0055] Preferably, in the embodiment of the present invention, the third thread segment 62 is a thread provided on at least a portion of the outer wall surface of the blocking body 61. The blocking body 61 and the third thread segment 62 are integrally formed, and the blocking body 61 is threadedly connected to the component to be verified via the third thread segment 62. Of course, in alternative embodiments not shown in the drawings of this application, the blocking body 61 and the third thread segment 62 can also be provided separately and connected according to actual needs, wherein the third thread segment 62 has external threads to facilitate connection with the component to be verified.

[0056] like Figure 1 and Figure 2 As shown, in an embodiment of the present invention, the blocking structure 60 further includes a stopper 63 connected to the blocking body 61. The stopper 63 is provided on the outer wall surface of the blocking body 61, and the third thread segment 62 is used to connect with the component to be checked. Therefore, at least part of the third thread segment 62 will extend into the inner cavity of the component to be checked. In order to prevent the blocking structure 60 from extending into the component to be checked, which makes it difficult to remove the blocking structure 60 and makes it difficult to disassemble the connector body 10 and the component to be checked, and also to prevent the internal thread of the blocking structure 60 from being disengaged from the external thread 14 during the movement of the blocking structure 60 relative to the connector body 10, which causes the blocking structure 60 to be disengaged from the external thread 14 of the connector body 10, so that the blocking structure 60 cannot well block the gap between the connector body 10 and the component to be checked, the technical solution of the present application enables the blocking structure 60 to include a stopper 63 to avoid the above-mentioned problem, ensure that the blocking structure 60 can well block the gap between the connector body 10 and the component to be checked, and facilitate assembly and disassembly.

[0057] Preferably, the stopper 63 is a sheet-like structure or a columnar structure provided on the outer wall surface of the blocking body 61 .

[0058] like Figure 1 and Figure 2 As shown, in the embodiment of the present invention, the blocking structure 60 further includes a second operating portion 64 connected to the blocking body 61. Under the action of an external force, the second operating portion 64 drives the blocking body 61 to move relative to the connector body 10. When the external force acts on the second operating portion 64, the blocking body 61 moves relative to the connector body 10 under the drive of the second operating portion 64, so that the internal thread of the blocking body 61 is threadedly engaged with the external thread 14 on the connector body 10, and the third thread segment 62 of the blocking body 61 is threadedly engaged with the component to be verified. If actual needs are met, the application of the external force is stopped, and both the connector body 10 and the component to be verified are threadedly connected to the blocking body 61, so that the blocking body 61 blocks the gap between the connector body 10 and the component to be verified.

[0059] Preferably, in the embodiment of the present invention, the second operating portion 64 is disposed on the outer wall of the blocking body 61, and the second operating portion 64 and the blocking body 61 are integrally formed. This arrangement can improve structural strength and connection stability. Of course, in alternative embodiments not shown in the drawings of this application, the second operating portion 64 can also be disposed separately from and connected to the blocking body 61, depending on actual needs.

[0060] Preferably, the structure of the second operating portion 64 is the same as that of the first operating portion 40, which will not be described in detail herein. Of course, the structure of the second operating portion 64 can also be different from that of the first operating portion 40 according to actual needs.

[0061] like Figure 2 As shown, in an embodiment of the present invention, along the fluid flow direction, the second operating portion 64, the stopper 63 and the third thread segment 62 are sequentially arranged on the blocking body 61. In other words, the distances between the third thread segment 62, the stopper 63 and the second operating portion 64 relative to the component to be verified increase in sequence. In this way, the blocking body 61 can be moved relative to the connector body 10 through the second operating portion 64, which is farther away from the component to be verified, so that the blocking body 61 can be threadedly engaged with the component to be verified through the third thread segment 62 or the blocking body 61 can be disengaged from the component to be verified. When the blocking body 61 is threadedly engaged with the component to be verified through the third thread segment 62, the stopper 63 can limit the extreme position of the blocking body 61 moving toward the component to be verified, so that the blocking structure 60 can always block the gap between the connector body 10 and the component to be verified.

[0062] like Figure 3 As shown, in an embodiment of the present invention, the oil pipe sealing verification method uses the above-mentioned sealing verification joint to perform sealing verification, and the oil pipe sealing verification method includes:

[0063] Step S10: Install the sealing test joint to the oil pipe to be tested; Step S20: Connect the fluid conveying equipment to the sealing test joint; Step S30: Convey the fluid through the sealing test joint into the oil pipe to be tested via the fluid conveying equipment, so that the pressure in the oil pipe to be tested increases to a predetermined value; Step S40: Stop conveying the fluid, observe the pressure drop in the oil pipe to be tested, and determine whether the pressure drop in the oil pipe to be tested exceeds 30% of the predetermined value within 3 to 5 minutes. If so, the oil pipe to be tested is not sealed; if not, the oil pipe to be tested is sealed.

[0064] In the above setting, the sealing joint of the present application is used to seal the oil pipe to be sealed. First, the sealing joint is installed on the oil pipe to be sealed, and then the fluid conveying equipment is connected to the sealing joint so that the inner cavity of the fluid conveying equipment, the flow cavity 11 of the sealing joint and the inner cavity of the oil pipe to be sealed are connected. In this way, the fluid can be conveyed into the oil pipe to be sealed through the sealing joint of the fluid conveying equipment, thereby increasing the pressure in the oil pipe to be sealed and increasing to a predetermined value.

[0065] In the above-mentioned process of conveying fluid into the oil pipe to be inspected and sealed, the technical solution of the present application is to convey fluid directly into the component to be inspected and sealed through the sealing joint of the fluid conveying equipment. Compared with the technology of conveying fluid into the oil pipe through the wellhead oil nozzle sleeve, making the pressure in the wellhead oil nozzle sleeve and the pressure at the back pressure valve the same as the pressure in the oil pipe, resulting in the pressure at the back pressure valve exceeding the working pressure of the back pressure valve, the oil pipe sealing method of the present application conveys fluid directly into the oil pipe to be inspected and sealed through the sealing joint, and the fluid will not enter the wellhead oil nozzle sleeve, so that the pressure in the wellhead oil nozzle sleeve and the pressure at the back pressure valve will not increase, which can avoid the problem of the pressure at the back pressure valve exceeding the working pressure of the back pressure valve, and thus the oil pipe to be inspected and sealed can be smoothly inspected and sealed.

[0066] After the pressure in the oil pipe to be inspected increases to a predetermined value, observe the pressure drop in the oil pipe to be inspected. If the pressure in the oil pipe to be inspected drops by more than 30% within 3 to 5 minutes (i.e., the pressure drop in the oil pipe to be inspected exceeds 30% of the predetermined value), it is determined that the oil pipe to be inspected is not sealed and there is a leak on the oil pipe to be inspected; otherwise, it is determined that the oil pipe to be inspected is sealed and there is no leak on the oil pipe to be inspected.

[0067] Preferably, in an embodiment of the present invention, the above-mentioned "predetermined value" is 5 MPa to 8 MPa.

[0068] It should be noted that the above-mentioned "sealed" means that there are no leaks on the oil pipe, and the oil and gas in the oil pipe cannot leak or leaks very little (for example, when the pressure in the oil pipe to be sealed increases to a predetermined value, within 3 to 5 minutes, the pressure drop in the oil pipe to be sealed is within 30% of the predetermined value) to the outside of the oil pipe, and "unsealed" means that there are leaks on the oil pipe, and the oil and gas in the oil pipe leak out of the oil pipe very quickly (for example, when the pressure in the oil pipe to be sealed increases to a predetermined value, within 3 to 5 minutes, the pressure drop in the oil pipe to be sealed exceeds 30% of the predetermined value).

[0069] Since the oil pipe sealing inspection method of the present application adopts the sealing inspection joint of the present application for sealing inspection, the oil pipe sealing inspection method of the present application also has the above-mentioned advantages of the sealing inspection joint of the present application, which will not be repeated here.

[0070] In an embodiment of the present invention, the oil pipe to be tested is connected to the wellhead device, and the sealing joint is connected to the oil pipe to be tested through the wellhead device to test the sealing of the oil pipe to be tested; wherein, the wellhead device is installed at the wellhead of oil and natural gas drilling, and the wellhead device is used to control the pressure and direction of gas and liquid fluids. The wellhead device includes a wellhead oil nozzle sleeve 80, a production valve and a back pressure valve, etc.

[0071] Specifically, if Figure 4 As shown, in an embodiment of the present invention, the oil pipe to be inspected is connected to a wellhead nozzle sleeve 80, and a production valve is provided at one end of the oil pipe to be inspected near the wellhead nozzle sleeve 80. The wellhead nozzle sleeve 80 has a cavity 81, a first opening 82 communicating with the cavity 81, a second opening 83 communicating with the cavity 81, and a third opening communicating with the cavity 81. The oil pipe to be inspected is arranged at the first opening 82, the wellhead nozzle sleeve 80 is connected to a back pressure valve, which is arranged at the second opening 83, the wellhead nozzle sleeve 80 is connected to a wellhead nozzle sleeve plug, which is arranged at the third opening. Before step S10, the oil pipe inspection method further includes:

[0072] Step S05: close the production valve and the back-pressure valve, drain the wellhead nozzle sleeve 80, remove the wellhead nozzle sleeve thread plug, and open the third opening.

[0073] Through the above steps, the wellhead nozzle sleeve 80 connected to the oil pipe to be tested can be emptied and the third opening can be opened. When it is necessary to perform a pressure test and a sealing test on the oil pipe to be tested, the sealing test joint is installed from the third opening into the cavity 81 of the wellhead nozzle sleeve 80, so that the fluid conveying equipment can be directly connected to the oil pipe to be tested through the sealing test joint, so that the flow cavity 11 of the fluid sealing test joint can be directly conveyed to the oil pipe to be tested, and then the pressure test and a sealing test can be performed on the oil pipe to be tested normally and smoothly.

[0074] The wellhead nozzle sleeve 80 has a cavity 81 and a first opening 82, a second opening 83 and a third opening all connected to the cavity 81; the oil pipe to be tested is connected to the wellhead nozzle sleeve 80, the inner cavity of the oil pipe to be tested is connected to the first opening 82, and the inner cavity of the oil pipe to be tested is connected to the cavity 81 through the first opening 82, and a production valve is provided between the oil pipe to be tested and the wellhead nozzle sleeve 80; the back pressure valve is connected to the wellhead nozzle sleeve 80, and the back pressure valve is located at the second opening 83; the wellhead nozzle sleeve thread plug is used to seal the third opening of the wellhead nozzle sleeve.

[0075] After the oil pipe is sealed, the oil pump will start to pump out the oil at the pump end, and then the oil pump will start to pump out the oil at the pump end.

[0076] Compared with the above technical solution, in the technical solution of the present application, the sealing joint is inserted into the cavity 81 of the wellhead oil nozzle sleeve 80, and the fluid conveying equipment is directly connected to the oil pipe to be sealed through the sealing joint. The fluid conveyed by the fluid conveying equipment is directly conveyed to the inner cavity of the oil pipe to be sealed through the flow cavity 11 of the sealing joint. The fluid will not enter the cavity 81 of the wellhead oil nozzle sleeve 80, and the pressure in the wellhead oil nozzle sleeve 80 will not increase. In this way, the pressure at the back pressure valve will not exceed the working pressure of the back pressure valve, so that the pressure test and sealing work of the oil pipe to be sealed can be carried out normally and smoothly.

[0077] like Figure 4 As shown, in the embodiment of the present invention, step S10 includes:

[0078] Step S11: Connect the first threaded section 20 to at least part of the inner wall surface of the wellhead nozzle sleeve 80, so that the flow cavity 11 of the joint body 10 is connected to the first opening 82; Step S12: Connect the sealing structure 60 to at least part of the inner wall surface of the wellhead nozzle sleeve 80, and use the sealing structure 60 to block the third opening.

[0079] In the above arrangement, the first threaded section 20 is connected to at least part of the inner wall surface of the wellhead nozzle sleeve 80, thereby achieving the purpose of connecting the joint body 10 to the oil pipe to be tested and sealed. The first threaded section 20 is located at the first opening 82, and the flow cavity 11 is connected to the inner cavity of the oil pipe to be tested and sealed through the first opening 82; the sealing structure 60 blocks the gap between the joint body 10 and at least part of the inner wall surface of the wellhead nozzle sleeve 80, and the sealing structure 60 blocks the third opening; through the above arrangement, the joint body 10 is arranged in the cavity 81 of the wellhead nozzle sleeve 80, and the joint body 10 is connected to at least part of the inner wall surface of the wellhead nozzle sleeve 80 through the first threaded section 20. The surfaces are connected, and the joint body 10 is connected to at least part of the inner wall surface of the wellhead nozzle sleeve 80 through the sealing structure 60. In this way, the flow cavity 11 of the joint body 10 is isolated and disconnected from the cavity 81 of the wellhead nozzle sleeve 80. The fluid transported by the fluid transporting equipment enters the flow cavity 11 through the inlet 12, and is then transported to the inner cavity of the oil pipe to be tested through the outlet 13 and the first opening 82. In the above process, the fluid will not enter the cavity 81 of the wellhead nozzle sleeve 80, and the pressure at the back pressure valve will not exceed the working pressure of the back pressure valve, so that the pressure test and sealing work of the oil pipe to be tested can be carried out normally and smoothly.

[0080] like Figure 4 As shown, in the embodiment of the present invention, between step S20 and step S30, the oil pipeline sealing verification method further includes:

[0081] Step S25: Open the production valve to connect the flow cavity 11 of the joint body 10 with the inner cavity of the oil pipe to be inspected and sealed.

[0082] The production valve is arranged between the oil pipe to be tested and the wellhead nozzle sleeve 80. Only when the production valve is opened can the flow cavity 11 of the sealing joint installed in the wellhead nozzle sleeve 80 be connected with the inner cavity of the oil pipe to be tested, and the fluid can pass through the flow cavity 11 into the oil pipe to be tested, thereby increasing the pressure in the oil pipe to be tested.

[0083] Specifically, in an embodiment of the present invention, the operating steps of the oil pipeline sealing verification method are as follows:

[0084] The first step is to stop the pumping unit, brake it, and cut off the power supply;

[0085] The second step is to close the wellhead production valve, then close the back pressure valve, open the vent valve to vent, and remove the wellhead oil nozzle thread plug;

[0086] The third step is to install the seal verification joint to the wellhead nozzle sleeve 80 and check that the sealing structure 70 is intact. First, screw the first threaded section 20 into the wellhead nozzle screw hole, tighten the first operating part 40 with a tool, and then screw the sealing structure 60 into the wellhead nozzle sleeve screw hole (located at the third opening of the wellhead nozzle sleeve) through the external thread 14 of the joint body 10. Tighten the second operating part 64 with a tool to isolate the passage between the wellhead production valve and the back pressure valve.

[0087] Step 4: Use the seal check connector to quickly connect the pump truck pipeline to the second threaded section 50, open the wellhead production valve, and make the flow cavity 11 unobstructed;

[0088] The fifth step is to start the pump and test the pressure. The high-pressure liquid after the pump truck is pressurized enters the oil pipe directly through the sealing joint and the wellhead production valve for pressure testing. When the pressure rises to 5MPa, stop the pump and observe the pressure drop of the pump truck (because the pump truck is connected to the oil pipe through the sealing joint installed on the wellhead nozzle sleeve of the wellhead device, the liquid pressure in the pump truck is the same as the liquid pressure in the oil pipe. By observing the pressure drop in the pump truck, the pressure drop in the oil pipe can be easily and intuitively reflected). If the pressure drops quickly (for example, within 3 to 5 minutes, the pressure drop in the oil pipe to be tested exceeds 30% of the preset value), it means that the oil pipe is not tightly sealed and there is a leak. Otherwise, it means that the oil pipe is sealed.

[0089] Step 6: Close the wellhead production valve, drain the pump truck, dismantle the pump truck pipeline and check the seal joints;

[0090] Step 7: Install the wellhead nozzle plug, close the vent valve, open the wellhead back pressure valve first, and then open the wellhead production valve;

[0091] Step 8: Turn on the power, release the brake, start the pump and resume production.

[0092] The present invention aims to address the overpressure phenomenon in the low-pressure part of the wellhead (that is, the problem that the pressure at the back-pressure valve exceeds the working pressure of the back-pressure valve) that occurs during the current pressure testing and sealing inspection of the oil pipeline in the pumping well. It provides a special joint for pressure testing the oil pipeline in the pumping well (that is, a sealing inspection joint) and a matching oil pipeline sealing inspection method to eliminate the safety hazards in this work.

[0093] The present invention provides a special joint for oil pipe pressure testing in an oil pumping well (i.e., a sealing joint) and a matching oil pipe sealing method. The sealing joint is installed at the wellhead of the oil pumping well and is quickly connected to the pipeline of a pump truck, thereby blocking the channel between the wellhead production valve and the back-pressure valve. The high-pressure liquid pressurized by the pump truck directly enters the oil pipe for pressure holding and sealing testing through the sealing joint and the wellhead production valve, thereby avoiding the phenomenon that the low-pressure part of the wellhead exceeds the working pressure (i.e., the problem that the pressure at the back-pressure valve exceeds the working pressure of the back-pressure valve) during the pressure testing and sealing testing of the oil pipe of the oil pumping well, thereby ensuring the smooth implementation of the work and improving work efficiency.

[0094] The present invention is applicable to the technical field of pressure testing and sealing of oil pipes in oil wells in the petroleum extraction industry. It can eliminate the phenomenon that the low-pressure part of the wellhead exceeds the working pressure during the pressure testing and sealing of the oil pipes in the oil wells, eliminate operational hazards, and improve work efficiency.

[0095] From the above description, it can be seen that the above-mentioned embodiments of the present invention achieve the following technical effects: the connector body is connected to the component to be tested through the first threaded section, the flow chamber is connected to the inner cavity of the component to be tested through the outlet, and the fluid is introduced into the flow chamber through the inlet. The fluid enters the inner cavity of the component to be tested through the outlet, so that the pressure in the component to be tested increases to a predetermined value, and then whether the component to be tested is sealed is determined according to the pressure change in the component to be tested, thereby completing the pressure test and sealing operation of the component to be tested. When the sealing test joint of the present application is used to perform a pressure test and sealing test on the oil pipe of the pumping well, the joint body is threadedly connected to at least a portion of the inner wall surface of the wellhead nozzle sleeve through the first threaded section or is directly threadedly connected to at least a portion of the inner wall surface of the oil pipe to be tested, so that the flow chamber is connected to the inner cavity of the oil pipe to be tested. In this way, fluid can be introduced into the flow chamber through the inlet of the joint body, and the fluid can enter the inner cavity of the oil pipe to be tested through the outlet, so that the pressure in the oil pipe to be tested is increased to a predetermined value, and it can be further determined whether the oil pipe to be tested is sealed. In the process of performing a pressure test and sealing test on the oil pipe of the pumping well using the sealing test joint of the present application, the fluid can directly enter the inner cavity of the oil pipe to be tested through the flow chamber without entering the cavity of the wellhead nozzle sleeve. In this way, the pressure in the wellhead nozzle sleeve and the pressure at the back pressure valve will not increase, thereby avoiding the problem that the pressure at the back pressure valve exceeds the working pressure of the back pressure valve, and the oil pipe of the pumping well can be pressure tested and sealed smoothly.

[0096] Obviously, the embodiments described above are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0097] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, tasks, devices, components and / or combinations thereof.

[0098] It should be noted that the terms "first," "second," and the like in the specification and claims of this application and the accompanying drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or precedence. It should be understood that the terms used in this manner are interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than that illustrated or described herein.

[0099] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A seal inspection joint, characterized in that: include: A joint body (10), the joint body (10) having a flow cavity (11), an inlet (12) communicating with the flow cavity (11), and an outlet (13) communicating with the flow cavity (11); a first threaded section (20) connected to the joint body (10), the first threaded section (20) being arranged on the outer wall surface of the joint body (10) and located at the end where the outlet (13) is located, and the joint body (10) is connected to the component to be calibrated via the first threaded section (20); A first operating portion (40) is provided on the joint body (10), and the joint body (10) can be mounted on the component to be calibrated by rotating the first operating portion (40); The seal verification joint further comprises a blocking structure (60) connected to the joint body (10), the blocking structure (60) being movably arranged relative to the joint body (10), and the blocking structure (60) being used to block the gap between the joint body (10) and the component to be verified; The sealing structure (60) includes a sealing body (61) arranged on the outer periphery of the joint body (10), at least a portion of the inner wall surface of the sealing body (61) is provided with an internal thread, and at least a portion of the outer wall surface of the joint body (10) is provided with an external thread (14) adapted to the internal thread, and the sealing body (61) and the joint body (10) are threadedly matched.

2. The seal inspection joint according to claim 1, characterized in that: The seal verification joint further comprises a second threaded section (50) arranged on the inner wall surface of the flow chamber (11), the second threaded section (50) being located at the end where the inlet (12) is located, and the joint body (10) is connected to the fluid conveying equipment via the second threaded section (50).

3. The seal inspection joint according to claim 2, characterized in that: The first operating portion (40) is located between the first thread segment (20) and the second thread segment (50).

4. The seal inspection joint according to claim 1, characterized in that: The blocking structure (60) further comprises a third thread segment (62) connected to the blocking body (61), the third thread segment (62) being provided on at least a portion of the outer wall surface of the blocking body (61), and the blocking body (61) being threadedly connected to the component to be checked via the third thread segment (62); or, The blocking structure (60) further includes a stopper (63) connected to the blocking body (61); or, The blocking structure (60) further comprises a second operating portion (64) connected to the blocking body (61), wherein under the action of an external force, the second operating portion (64) drives the blocking body (61) to move relative to the joint body (10); or, The blocking structure (60) further comprises a third threaded section (62), a stopper (63) and a second operating portion (64); along the fluid flow direction, the second operating portion (64), the stopper (63) and the third threaded section (62) are sequentially arranged on the blocking body (61).

5. The seal inspection joint according to any one of claims 1 to 3, characterized in that: The seal verification joint further comprises a sealing structure (70) provided on the first threaded section (20), the sealing structure (70) being used to seal the connection between the first threaded section (20) and the component to be verified; or, The first operating portion (40) comprises an operating block (41) arranged on at least a portion of the outer wall surface of the connector body (10), and the operating block (41) has at least two outer wall surfaces arranged at an angle.

6. A method for checking the sealing of an oil pipe, characterized in that: The oil pipe sealing verification method uses the sealing verification joint according to any one of claims 1 to 5 to perform sealing verification, and the oil pipe sealing verification method includes: Step S10: Installing the seal inspection connector to the oil pipe to be inspected; Step S20: Connecting the fluid delivery device to the seal verification connector; Step S30: using the fluid conveying device to convey the fluid through the seal checking joint into the oil pipe to be inspected, so that the pressure in the oil pipe to be inspected increases to a predetermined value; Step S40: Stop delivering the fluid, observe the pressure drop in the oil pipe to be inspected, and determine whether the pressure drop in the oil pipe to be inspected exceeds 30% of the predetermined value within 3 minutes to 5 minutes. If so, the oil pipe to be inspected is not sealed; if not, the oil pipe to be inspected is sealed.

7. The oil pipe sealing inspection method according to claim 6, characterized in that: The oil pipe to be tested is connected to a wellhead oil nozzle sleeve (80), and a production valve is provided at one end of the oil pipe to be tested close to the wellhead oil nozzle sleeve (80). The wellhead oil nozzle sleeve (80) has a cavity (81), a first opening (82) communicating with the cavity (81), a second opening (83) communicating with the cavity (81), and a third opening communicating with the cavity (81). The oil pipe to be tested is arranged at the first opening (82), the wellhead oil nozzle sleeve (80) is connected to a back pressure valve, and the back pressure valve is arranged at the second opening (83). The wellhead oil nozzle sleeve (80) is connected to a wellhead oil nozzle sleeve plug, and the wellhead oil nozzle sleeve plug is arranged at the third opening. Before step S10, the oil pipeline sealing verification method further includes: Step S05: closing the production valve and the back-pressure valve, venting the wellhead nozzle sleeve (80), removing the wellhead nozzle sleeve thread plug, and opening the third opening.

8. The oil pipe sealing inspection method according to claim 7, characterized in that: The step S10 includes: Step S11: connecting the first threaded section (20) to at least a portion of the inner wall surface of the wellhead nozzle sleeve (80) so that the flow cavity (11) of the joint body (10) is in communication with the first opening (82); Step S12: connecting the blocking structure (60) to at least a portion of the inner wall surface of the wellhead nozzle sleeve (80), and blocking the third opening using the blocking structure (60).

9. The oil pipe sealing inspection method according to claim 7, characterized in that: Between step S20 and step S30, the oil pipeline sealing verification method further includes: Step S25: Open the production valve to connect the flow cavity (11) of the joint body (10) with the inner cavity of the oil pipe to be tested and sealed.

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