Oil casing air tightness detection device and detection method thereof

Abstract

The invention discloses an oil casing air tightness detection device and a detection method thereof. The oil casing air tightness detection device comprises a first power source, a setting mechanism, a pressurizing mechanism and a second power source which are connected in sequence, the setting mechanism comprises a setting cavity shell, a force transfer medium, a sealing rubber cylinder and a first piston; a to-be-detected position is located between the two sealing rubber cylinders; the first power source drives the first piston to pressurize the force transmission medium, so that the rubber sleeve expands to seal the oil pipe; the pressurizing mechanism comprises a pressurizing cavity shell, detection gas and a second piston; and the second power source drives the second piston to compress the detection gas, so that the detection gas enters a space between the two sealing rubber cylinders, and airtightness detection is carried out. The first power source and the second power source are respectively controlled through the control equipment, so that the setting mechanism and the pressurizing mechanism are respectively controlled; ground large supercharging equipment is reduced, safety risks caused by manual operation of high-pressure equipment are avoided, meanwhile, the labor intensity of workers is reduced through automation of the detection process, and convenience is improved.

Description

Technical Field

[0001] The invention relates to the technical field of oil casing air tightness detection, and in particular to an oil casing air tightness detection device and a detection method thereof. Background Art

[0002] For gas-driven oil production and gas storage injection and production wells, the sealing of the oil casing connection is an important factor affecting the long-term stable production of the injection and production wells and whether the annulus is pressurized. The error in pipe processing and the cleanliness of the threaded sealing surface all affect the sealing. In order to ensure the sealing of the oil casing connection entering the well, gas injection and production wells must use gas-tight oil casing, and require gas sealing detection for each oil casing connection during the lowering process.

[0003] The existing gas seal detection process is to use a steel wire rope to lower the detection tool to a predetermined position, use ground booster equipment to increase the low-pressure helium and nitrogen mixed gas to a certain pressure, seal the detection tool, and perform helium leakage detection on the oil casing connection. This conventional detection method is equipped with large booster and high-pressure equipment (including boosters and energy storage devices) on the ground, and the booster is manually operated. Due to the well site environment, the distance between the equipment and people is relatively close, which poses certain safety risks; and each booster and depressurization takes a long time, which reduces the operation efficiency and seriously affects the development of the speed-up of well repair operations. Summary of the invention

[0004] The embodiment of the present invention provides an oil casing air tightness detection device and a detection method thereof, thereby solving the technical problem in the prior art that the sealing detection of the oil casing connection requires external large-scale equipment for pressurization and pressure relief. By integrating the pressurization and sealing equipment and realizing automatic operation by using the control equipment, the technical effect of reducing large-scale high-pressure equipment on the ground and reducing the labor intensity of workers by using automatic operation is achieved.

[0005] In the first aspect, in order to solve the above technical problems, the embodiments of the present invention provide the following technical solutions:

[0006] An oil casing gas tightness detection device, comprising:

[0007] A first power source, a sealing mechanism, a pressurizing mechanism, and a second power source are connected in sequence; the first power source and the second power source are connected to a control device;

[0008] The above-mentioned sealing mechanism comprises a sealing cavity shell, a force transmission medium arranged in the above-mentioned sealing cavity shell, a sealing rubber cylinder arranged on the outer wall of the above-mentioned sealing cavity shell and connected to the above-mentioned sealing cavity, and a first piston sliding in the above-mentioned sealing rubber cylinder; there are two sealing rubber cylinders, and the position to be detected is located between the two sealing rubber cylinders;

[0009] The first power source drives the first piston to pressurize the force transmission medium, so that the rubber cylinder expands and seals the oil pipe;

[0010] The boost mechanism comprises a boost chamber housing, a detection gas arranged in the boost chamber housing, and a second piston sliding in the boost chamber housing;

[0011] The second power source drives the second piston to compress the detection gas, so that the detection gas enters the space between the two sealing rubber cylinders, and the detection instrument performs airtightness detection.

[0012] Optionally, the first power source and the second power source both include an outer cylinder, a motor and a screw transmission mechanism disposed in the outer cylinder;

[0013] The lead screw of the lead screw transmission mechanism is connected to the motor;

[0014] The nut of the screw transmission mechanism, under the constraint of the guide groove on the outer cylinder, drives the center piece along a linear trajectory to push the corresponding piston, so that the piston slides in the seat sealing chamber shell or the boost chamber shell.

[0015] Optionally, a reducer is provided between the motor and the lead screw to adjust the rotation speed and torque of the lead screw.

[0016] Optionally, an electrically controlled valve is provided on the air hole, and the electrically controlled valve is opened when the sealing mechanism completes the sealing, and is closed when the second piston is reset to the initial position.

[0017] Optionally, the device further comprises a hydraulic cylinder, an output end of the hydraulic cylinder is connected to the sealing rubber cylinder, and an input end of the hydraulic cylinder is communicated with the seat sealing cavity; the hydraulic cylinder pushes the compressed rubber cylinder to expand.

[0018] Optionally, the first power source and the second power source are connected to an external power supply device via a cable.

[0019] Optionally, the above-mentioned device also includes a cable car equipped with a cable, and the above-mentioned cable car controls the lowering depth of the above-mentioned detection device by controlling the lowering length of the cable.

[0020] In a second aspect, a method for detecting gas tightness of an oil casing is provided, comprising the detection device of the first aspect; the method comprises:

[0021] Start the cable car and lower the above detection device to the preset position;

[0022] In response to the sealing signal of the control device, the first power source drives the first piston to pressurize the force transmission medium, so that the rubber cylinder expands and seals the oil pipe;

[0023] In response to the pressurization signal of the control device, the second power source drives the second piston to compress the detection gas into the space between the two sealing rubber cylinders to a preset pressure value; and the detection instrument arranged on the oil pipe is used to detect the air tightness of the space.

[0024] Optionally, the above-mentioned detection instrument sends the acquired airtightness-related parameters to the control device for storage;

[0025] In response to the pressure relief signal of the control device, the second power source drives the second piston to relieve pressure, and recovers the detection gas through the air hole;

[0026] In response to the unsealing signal of the control device, the first power source drives the first piston to release the pressure of the force transmission medium, so as to reset the sealing rubber cylinder.

[0027] According to a third aspect, an electronic device is provided, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the method steps of the second aspect when executing the computer program.

[0028] One or more technical solutions provided in the embodiments of the present invention have at least the following technical effects or advantages:

[0029] In the embodiment of the present invention, the detection device uses an integrated detection device of the sealing mechanism and the boosting mechanism; the large-scale boosting equipment on the ground is reduced, and the high-pressure equipment does not need to be operated manually, which reduces the safety risk of workers. In addition, the sealing mechanism and the boosting mechanism use different power sources respectively, so that the sealing and detection are controlled separately, and the mechanical structure is simple and easy to implement.

[0030] The detection method utilizes a control device to control a first power source and a second power source to automatically complete the sealing and pressurization of the detection device, and feeds back detection data through a detection instrument to automate the entire detection process, thereby reducing the labor intensity of staff and improving convenience. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0032] Figure 1 A schematic diagram of the overall structure of an oil casing gas tightness detection device provided by the present invention;

[0033] Figure 2 It is a structural schematic diagram of the screw transmission mechanism in the present invention;

[0034] Figure 3 It is a structural schematic diagram of the seat sealing mechanism in the present invention;

[0035] Figure 4 It is a structural schematic diagram of the boosting mechanism in the present invention;

[0036] Figure 5 The present invention provides a flow chart of a method for detecting gas tightness of oil casing.

[0037] Figure numerals: 1. first power source; 11. motor; 12. screw transmission mechanism; 121. retaining ring; 122. screw; 123. bearing; 124. nut; 125. center rod; 126. outer cylinder; 2. sealing mechanism; 21. first piston; 22. force transmission medium; 23. sealing rubber cylinder; 24. sealing chamber shell; 25. hydraulic cylinder; 3. boosting mechanism; 31. second piston; 32. detection gas; 33. air hole; 34. boosting chamber shell; 4. second power source. DETAILED DESCRIPTION

[0038] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0039] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0040] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0041] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set" and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. In addition, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0042] It should be understood that the embodiments of the present invention and the specific features in the embodiments are detailed descriptions of the technical solutions of the present application, rather than limitations of the technical solutions of the present application. In the absence of conflict, the embodiments of the present application and the technical features in the embodiments may be combined with each other.

[0043] The technical solution of the embodiment of the present invention is to solve the above technical problems, and the overall idea is as follows:

[0044] The original large-scale ground pressurization equipment is changed into a detection device integrating the sealing mechanism 2 and the pressurization mechanism 3; at the same time, the sealing mechanism 2 and the pressurization mechanism 3 are controlled by the control equipment to realize remote automatic control and improve the operation efficiency. Thus, the large-scale ground pressurization equipment is reduced, the high-pressure equipment does not need to be operated manually, and the safety risk of workers is reduced.

[0045] In an embodiment of the present invention, there is provided Figure 1 , Figure 2 , Figure 3 and Figure 4The oil casing air tightness detection device shown includes: a first power source 1, a sealing mechanism 2, a boosting mechanism 3, and a second power source 4 connected in sequence; the first power source 1 and the second power source 4 are connected to the control device; the sequential connection is because in the oil casing, the series connection can better adapt to the shape of the oil casing, making it more convenient to lower the detection device. Similarly, if a power source is used in the oil casing to drive the sealing mechanism 2 and the boosting mechanism 3, a more complex structure must be used, and it is difficult to control them separately. Therefore, the first power source 1 and the second power source 4 are used to simplify the mechanical structure, and the sealing and detection can be controlled separately, which is easy to achieve. The sealing mechanism 2 includes a sealing chamber shell 24, a force transmission medium 22 arranged in the sealing chamber shell 24, a sealing rubber tube 23 arranged on the outer wall of the sealing chamber shell 24 and connected to the sealing chamber, and a first piston 21 sliding in the sealing chamber shell 24; there are two sealing rubber tubes 23, and the position to be detected is located between the two sealing rubber tubes 23; wherein the sealing chamber shell 24 is mainly used to place the force transmission medium 22 and the piston, and the force transmission medium 22 can be hydraulic oil, etc. Specifically, the first power source 1 drives the first piston 21 to pressurize the force transmission medium 22, so that the rubber tube expands and seals the oil pipe; thereby isolating the space between the two sealing rubber tubes 23 from the space outside, preventing the detection gas 32 from flowing into other positions of the wellbore, thereby reducing the use of the detection gas 32. The boosting mechanism 3 includes a boosting chamber shell 34, a detection gas 32 arranged in the boosting chamber shell 34, and a second piston 31 sliding in the boosting chamber shell 34; wherein the boosting chamber shell 34 is used to place the detection gas 32, and the second piston 31 is used to pressurize the detection gas 32. The second power source 4 drives the second piston 31 to compress the detection gas 32, so that the detection gas 32 enters the space between the two sealing rubber cylinders 23; an air hole 33 can be set here to connect the booster chamber and the space between the two sealing rubber cylinders 23, so as to realize the transmission of gas. Finally, the air tightness test is performed by the detection instrument. The detection instrument can be set at the connection of the oil casing, or it can be set between the two sealing rubber cylinders 23 on the detection device. Specifically, an airtightness detector can be used for measurement.

[0046] Furthermore, if Figure 2 As shown, the first power source 1 and the second power source 4 both include an outer cylinder 126, a motor 11 and a screw transmission mechanism 12 arranged in the outer cylinder 126; the screw 122 of the screw transmission mechanism 12 is connected to the motor 11; the nut 124 of the screw transmission mechanism 12 is constrained by the guide groove on the outer cylinder 126, and drives the center piece along a linear trajectory to push the corresponding piston, so that the piston slides in the seat sealing chamber shell 24 or the boost chamber shell 34.

[0047] It should be noted that the outer cylinder 126 is mainly used to carry the motor 11 and the screw transmission mechanism 12 and protect them. The screw transmission mechanism 12 is mainly used to convert the rotational motion of the motor 11 into linear motion. Specifically, the output shaft of the motor 11 is connected to the screw 122 by a special-shaped hole, which can transmit torque. Two bearings 123 are installed at the screw 122. The retaining ring 121 of the bearing 123 is threadedly connected to the outer cylinder 126 of the nut 124, which plays the role of fixed support and pre-tightening the bearing 123. The nut 124 is threadedly connected to the screw. The upper part of the screw nut 124 has a guide key, which cooperates with the guide groove inside the outer cylinder 126 of the screw nut 124. When the screw rotates, the guide groove limits the rotation of the screw nut 124, and the nut 124 can only move linearly. The screw nut 124 is threadedly connected to the center rod 125, and the center piece is the output end of the linear motion. Similarly, the first power source 1 and the second power source 4 can also directly use the hydraulic cylinder 25. Compared with the screw transmission mechanism 12, the screw has fewer components, is easy to maintain, has good stability and no risk of leakage, so the screw transmission mechanism 12 is preferred. In addition, a reducer is also provided between the motor 11 and the screw to adjust the speed and torque of the screw.

[0048] Furthermore, an electric control valve is provided on the air hole 33 , and the electric control valve is opened when the sealing mechanism 2 completes the sealing, and is closed when the second piston 31 is reset to the initial position.

[0049] It should be noted that although a blocking object is set on the air hole 33, the air tightness detection can be achieved by squeezing out the blocking object when pressurized. However, when it is recovered, the detection gas 32 will also leak partially. Therefore, an electrically controlled valve is set, and it is set by a control device, that is, when the sealing mechanism 2 completes the sealing, the control device is fed back to control the electrically controlled valve to open; and for the closing of the electrically controlled valve, a preset time can be set according to the time it takes for the second piston 31 to move to the initial position. After the detection instrument has completed the detection, the control device starts timing, and the electrically controlled valve is closed when the preset time is reached. In addition, a position sensor or a pressure sensor can be set at the initial position of the second piston 31 to detect whether it is reset to the initial position.

[0050] Furthermore, if Figure 3 As shown, the device also includes a hydraulic cylinder 25, the output end of the hydraulic cylinder 25 is connected to the sealing rubber cylinder 23, and the input end of the hydraulic cylinder 25 is connected to the seat sealing cavity; the hydraulic cylinder 25 pushes the compressed rubber cylinder to expand.

[0051] It should be noted that the sealing rubber tube 23 can also be directly aligned with the force transmission medium 22 for extrusion and expansion to complete the sealing, but the force transmission medium 22 is a liquid and directly contacts the sealing rubber tube 23 for extrusion, which has high requirements for sealing. Therefore, a hydraulic cylinder 25 is provided to fix the sealing rubber tube 23 on the hydraulic cylinder 25, so that the sealing is more stable and reliable, and the displacement or falling off of the sealing rubber tube 23 during the sealing process is avoided.

[0052] Furthermore, the first power source 1 and the second power source 4 are connected to an external energy supply device via a cable. Specifically, the cable car carrying the cable controls the lowering length of the cable to control the lowering depth of the detection device, thereby determining whether the detection device has reached a specified depth, thereby improving convenience.

[0053] Based on the same inventive concept, the embodiment of the present invention provides Figure 5 A method for detecting gas tightness of oil casing is shown, the method comprising steps S101 to S103:

[0054] Step S101, start the cable car to lower the detection device to a preset position;

[0055] It should be noted that, on the ground, the cable is sealed with a pin and a loop, and then sealed with a thread of the cable head and the detection device; then the cable car is started and slowly moved downward, and the length below is used to determine whether the detection device has reached the preset position, that is, the oil pipe sleeve connection.

[0056] Step S102, in response to the sealing signal of the control device, the first power source 1 drives the first piston 21 to pressurize the force transmission medium 22, so that the rubber cylinder expands and seals the oil pipe;

[0057] It should be noted that after reaching the preset position, the ground control personnel send a sealing signal through the control device to control the motor 11 of the first power source 1 to rotate forward, and through the reduction mechanism, reach a speed and torque that matches the screw transmission mechanism 12. The screw nut 124 drives the center rod 125 to move downward to compress the force transmission medium 22 in the sealing mechanism 2, so that the sealing rubber cylinder 23 expands, seals the oil pipe, and completes the isolation of the space at the connection between the oil casing and other spaces.

[0058] Step S103, in response to the pressurization signal of the control device, the second power source 4 drives the second piston 31 to compress the detection gas 32, which enters the space between the inner wall of the oil casing and the sealing rubber cylinder 23 to a preset pressure value; and uses the detection instrument set on the oil pipe to detect the air tightness of the space.

[0059] It should be noted that after the seat seal is reliable, the ground operator sends a pressurization signal through the control equipment, and the motor 11 of the second power source 4 rotates forward, driving the screw nut 124 to push the detection gas 32 in the compression chamber of the second piston 31. The gas enters the space between the two sealing rubber cylinders 23 through the air inlet hole 33 and continues to compress the gas. After the pressure increases to the required pressure value (i.e., the preset pressure value), it stabilizes for 15 to 20 seconds, and the air tightness of the space is detected using the detection instrument installed on the oil pipe.

[0060] Furthermore, recovery is required after detection, so the method also includes:

[0061] Step S104, the detection instrument sends the acquired airtightness related parameters to the control device for storage;

[0062] It should be noted that once the control device obtains airtightness related parameters (such as the change in air pressure within a certain period of time), it means that the detection is completed, and the detection device is recovered.

[0063] Step S105, in response to the pressure relief signal of the control device, the second power source 4 drives the second piston 31 to relieve pressure, and recovers the detection gas 32 through the air hole 33;

[0064] It should be noted that the detection device should recover the detection gas 32 first. If it is unsealed first, the detection gas 32 will overflow. Therefore, the control device sends a pressure relief signal to the second power source 4 to drive the second piston 31 to relieve the pressure. Since the external pressure of the boost chamber is greater than the internal pressure at this moment, the gas flows into the boost chamber.

[0065] Step S106 , in response to the unsealing signal of the control device, the first power source 1 drives the first piston 21 to release the pressure of the force transmission medium 22 , and the sealing rubber cylinder 23 is reset by its own elastic force without external compression.

[0066] Based on the same inventive concept, an embodiment of the present invention provides an electronic device, including: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements an oil casing air tightness detection method when executing the computer program.

[0067] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0068] Although the preferred embodiments of the present invention have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0069] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. An oil casing gas tightness detection device, characterized in that: The device comprises: A first power source, a sealing mechanism, a pressurizing mechanism, and a second power source are connected in sequence; the first power source and the second power source are connected to a control device; The seat sealing mechanism comprises a seat sealing cavity shell, a force transmission medium arranged in the seat sealing cavity shell, a sealing rubber cylinder arranged on the outer wall of the seat sealing cavity shell and connected to the seat sealing cavity, and a first piston sliding in the seat sealing cavity shell; there are two sealing rubber cylinders, and the position to be detected is located between the two sealing rubber cylinders; The first power source drives the first piston to pressurize the force transmission medium, so that the rubber cylinder expands and seals the oil pipe; The pressurizing mechanism comprises a pressurizing chamber housing, a detection gas arranged in the pressurizing chamber housing, and a second piston sliding in the pressurizing chamber housing; The second power source drives the second piston to compress the detection gas, so that the detection gas enters the space between the two sealing rubber cylinders, and the detection instrument performs airtightness detection on the space.

2. The detection device according to claim 1, characterized in that The first power source and the second power source both include an outer cylinder, a motor and a screw transmission mechanism disposed in the outer cylinder; The lead screw of the lead screw transmission mechanism is connected to the motor; The nut of the screw transmission mechanism, under the constraint of the guide groove on the outer cylinder, drives the center piece along a linear trajectory to push the corresponding piston, so that the piston slides in the seat sealing chamber shell or the boost chamber shell.

3. The detection device according to claim 2, characterized in that: A speed reducer is also provided between the motor and the lead screw to adjust the rotation speed and torque of the lead screw.

4. The detection device according to claim 1, characterized in that: An electric control valve is provided on the air hole. The electric control valve is opened when the sealing mechanism completes the sealing, and is closed when the second piston is reset to the initial position.

5. The detection device according to claim 1, characterized in that: The device also includes a hydraulic cylinder, the output end of the hydraulic cylinder is connected to the sealing rubber cylinder, and the input end of the hydraulic cylinder is communicated with the seat sealing cavity; the hydraulic cylinder pushes the compressed rubber cylinder to expand.

6. The detection device according to any one of claims 1 to 5, characterized in that: The first power source and the second power source are connected to an external power supply device via cables.

7. The detection device according to claim 6, characterized in that: The device also includes a cable car carrying a cable, and the cable car controls the lowering depth of the detection device by controlling the lowering length of the cable.

8. A method for detecting gas tightness of oil casing, characterized in that: comprising a detection device as claimed in any one of claims 1 to 7; The method comprises: Starting the cable car to lower the detection device to a preset position; In response to the sealing signal of the control device, the first power source drives the first piston to pressurize the force transmission medium, so that the rubber cylinder expands and seals the oil pipe; In response to the pressurization signal of the control device, the second power source drives the second piston to compress the detection gas, which enters the space between the two sealing rubber cylinders to a preset pressure value; and the air tightness of the space is detected using the detection instrument arranged on the oil pipe.

9. The detection method according to claim 8, characterized in that: The method further comprises: The detection instrument sends the acquired airtightness related parameters to the control device for storage; In response to a pressure relief signal from the control device, the second power source drives the second piston to relieve pressure, and recovers the detection gas through the air hole; In response to the unsealing signal of the control device, the first power source drives the first piston to release the pressure of the force transmission medium to reset the sealing rubber cylinder.

10. An electronic device, characterized in that: The electronic device comprises: a memory, a processor, and a computer program stored in the memory and executable on the processor, and the processor implements the method steps described in any one of claims 8 to 9 when executing the computer program.

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