Micro-resistivity scanning imager capable of measuring downwards
Through the combined structure of the main pole module, power arm, slave arm and power drive module, the problem of snapping in the microresistivity scanning imager when the well wall is uneven is solved, and the two-way logging is realized upward and lowered, improving the logging efficiency and imaging quality.
Patent Information
- Application Number
- CN202510555640.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-29
- Publication Date
- 2025-08-01
AI Technical Summary
Existing microresistivity scanning imagers are prone to electrode arms snapping into the well wall when the well wall is uneven, resulting in reduced logging efficiency and damage to the push-back system.
The combination structure of main rod module, power arm, driven arm, acquisition component and power drive module is adopted to form an isosceles trapezoidal structure, combined with the power link, support and roller design, to ensure that the collection component is closely attached to the well wall, and the internal liquid and external mud pressure are balanced through the balance module, so as to achieve upward and lowered bidirectional logging.
Improves logging efficiency and operational safety, reduces mud intrusion, improves the quality and reliability of micro-resistivity scanning imaging, and performs well especially in complex wellbore environments.
Smart Images
Figure CN120402067A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of micro-resistivity scanning imaging, and particularly to a downhole-measurable micro-resistivity scanning imager. Background Art
[0002] At present, the micro-resistivity scanning imager is an important tool in the field of oil exploration and can provide high-resolution resistivity images of the formation around the wellbore. Such instruments have unique advantages in detecting complex lithologies and fractured hydrocarbon reservoirs, greatly promoting the development of oil extraction technology and providing strong support for improving the exploration efficiency and accuracy of oil and gas resources. In practical applications, the micro-resistivity scanning imager pushes the measurement surface of the pole bean signal acquisition module against the wellbore surface and moves along the wellbore to collect data. Finally, the data processing board in the main line calculates and stores or uploads the data to the surface system.
[0003] In related technologies, in order to achieve the pushing function during the logging process, a parallelogram pushing structure is usually adopted. The parallelogram pushing structure pushes the pole bean signal acquisition module against the wellbore through mechanical transmission. However, the wellbore is mostly uneven, so that the micro-resistivity scanning imager is prone to the situation that the electrode arm gets stuck in the wellbore during the downhole logging process, resulting in damage to the pushing system. Furthermore, when using the micro-resistivity scanning imager for logging, it is necessary to first lower the micro-resistivity scanning imager to a predetermined position, then lift it up and conduct logging, which leads to the problem of reduced logging efficiency.
[0004] Therefore, there is an urgent need for a downhole-measurable micro-resistivity scanning imager. Summary of the Invention
[0005] In order to improve the logging efficiency and enhance the operation safety, the present application provides a downhole-measurable micro-resistivity scanning imager.
[0006] A downhole-measurable micro-resistivity scanning imager provided by the present application adopts the following technical solutions: A downhole-measurable micro-resistivity scanning imager includes: A main rod module; A plurality of electrode arm modules arranged circumferentially around the main rod module. The electrode arm module includes a power arm, a driven arm, and a collection component. The collection component is respectively hinged to the power arm and the driven arm. One end of the driven arm away from the collection component is hinged to the main rod module. One end of the power arm away from the collection component is movably connected to the main rod module. A support member is movably connected between the power arm and the main rod module; A power drive module disposed in the main rod module and connected to a plurality of the power arms. The power drive module is used to drive the plurality of power arms to move; A balance module is provided on the main rod module, and the balance module is used to balance the pressure of the liquid inside the main rod module and the external mud.
[0007] By adopting the above technical solution, when the power drive module drives the power arm to move, the power arm, the driven arm, and the acquisition component can move synchronously, so that the power arm, the driven arm, the acquisition component, and the main rod module can form an isosceles trapezoid structure, enabling the micro-resistivity scanning imager to perform well logging during both the lowering and raising processes, thereby effectively improving the well logging efficiency. Moreover, the power arm, the power drive module, and the support can form a stable triangular-like support structure, significantly enhancing the pushing force and stability of the electrode arm module, ensuring that the measurement surface of the acquisition component can closely fit the wellbore surface, reducing the mud invasion between the measurement surface and the wellbore surface, and thus improving the quality of micro-resistivity scanning imaging. In addition, the setting of the balance module effectively balances the pressure of the liquid inside the main rod module and the external mud, preventing the external mud from invading the inside of the main rod module, and thus ensuring the normal power supply and operation of the power drive module.
[0008] Optionally, the power arm includes a power arm body, a connecting pin, and a power link. One end of the power arm body is hinged to the acquisition component, the other end of the power arm body is slidably connected to the main rod module and hinged to the power link. The end of the power link away from the power arm body is connected to the power drive module. The connecting pin is provided on the power arm body. One end of the support is hinged to the main rod module, and a chute is provided along the length direction of the other end of the support. The connecting pin is slidably inserted into the chute.
[0009] By adopting the above technical solution, one end of the power arm body is hinged to the acquisition component, and the other end is slidably connected to the main rod module and hinged to the power link. Thus, when the power drive module drives the power link to move linearly, the power link can drive the power arm body to rotate. At this time, the power arm body can drive the support to rotate through the connecting pin, so that a triangular-like support structure is formed among the support, the power link, and the power arm body, significantly increasing and stabilizing the pushing force of the electrode arm module, ensuring that the measurement surface of the acquisition component can be more parallel and closely attached to the wellbore surface, further reducing the possibility of mud invading the measurement attachment surface, and thus improving the quality of micro-resistivity imaging and the reliability of well logging. This structural optimization effectively improves the ability of the electrode arm module to pass through complex wellbore environments during well logging, especially performing well in highly deviated wells or horizontal wells.
[0010] Optionally, a power shaft pin is provided on the power arm body. The power shaft pin is rotatably connected to the power link, and a roller is provided on the power shaft pin. The roller is rollingly connected to the main rod module.
[0011] By adopting the above technical solution, the setting of the power shaft pin enables the connection between the power connecting rod and the power arm body to achieve rotation. This rotational connection method significantly reduces the friction force during the relative movement of the two. At the same time, the introduction of the roller further converts the sliding friction into rolling friction, making the movement of the power arm body on the main rod module smoother and effectively reducing the energy loss during the power transmission process. This design not only improves the stability of the operation of the entire device but also ensures that the power output by the power drive module can be transmitted to the electrode arm module more efficiently, thus ensuring the smooth operation of the micro-resistivity scanning imager in a complex wellbore environment. In addition, the rolling connection method between the roller and the main rod module also helps to maintain the smoothness of the electrode arm module during the opening or retracting process, avoiding component wear caused by excessive friction and extending the service life of the equipment.
[0012] Optionally, a lower torsion spring is provided between the power arm body and the acquisition component.
[0013] By adopting the above technical solution, the lower torsion spring can apply an outward tension to the power arm body, enabling the acquisition component to maintain a stable posture during the pushing process and avoiding unstable factors brought by the movement of the power arm body from affecting the measurement accuracy. In addition, the elastic characteristics of the lower torsion spring also help the acquisition component to adapt to the changes in the wellbore wall shape in a timely manner when encountering a complex wellbore wall environment during the logging process, thereby improving the fitting degree between the pole bean signal acquisition module and the wellbore wall surface, reducing the possibility of mud invasion, and further enhancing the quality and stability of the micro-resistivity scanning imaging.
[0014] Optionally, the power drive module includes a driving member and a power push rod. The driving member is arranged inside the main rod module. The power push rod is coaxially arranged inside the main rod module and is connected to the driving member. A dynamic seal sleeve is arranged inside the main rod module. One end of the power push rod away from the driving member passes through the dynamic seal sleeve and is connected to the power connecting rod. The driving member is used to drive the power push rod to move linearly.
[0015] By adopting the above technical solution, the driving member can drive the power push rod to move linearly. The power push rod is connected to the power connecting rod, and the thrust or pull is transmitted through the linear movement to achieve precise control of the power arm, thereby adjusting the opening or retracting state of the electrode arm module. And the setting of the dynamic seal sleeve, on the one hand, can straighten the power push rod to ensure the stability and accuracy of the movement of the power push rod and the power connecting rod; on the other hand, it effectively isolates the liquid inside and outside the main rod module, avoiding external mud from entering the inside and affecting the normal operation of the equipment.
[0016] Optionally, the driven arm includes a driven arm body and an elastic member. One end of the driven arm body is hinged to the acquisition assembly, and the other end of the driven arm body is hinged to the main rod module. The elastic member is disposed between the driven arm body and the main rod module and is used to drive the driven arm body to open.
[0017] By adopting the above technical solution, the elastic member between the driven arm body and the main rod module can provide an outward tension for the driven arm body during the logging process. This tension ensures that the driven arm body can stably push the acquisition assembly to expand towards the wellbore wall, so that the measurement surface of the acquisition assembly fits more closely and parallel to the wellbore wall surface. This design not only helps to reduce the intrusion of wellbore mud into the gap between the measurement surface of the acquisition assembly and the wellbore wall, but also significantly improves the accuracy and quality of the micro-resistivity scanning imaging. In addition, the method of using the elastic member to drive the driven arm body to open can also enhance the structural stability of the entire device, enabling the electrode arm module to have better adaptability in the face of complex wellbore environments and ensuring the smooth completion of the logging operation.
[0018] Optionally, the elastic member includes a pouting spring, a leaf spring and an upper torsion spring. One end of the pouting spring is connected to the driven arm body, and the other end of the pouting spring is movably disposed on the main rod module. One end of the leaf spring is slidably disposed on the driven arm body, and the other end of the leaf spring is disposed on the main rod module. The upper torsion spring is disposed between the driven arm body and the acquisition assembly.
[0019] By adopting the above technical solution, the combined structure of the pouting spring, the leaf spring and the upper torsion spring is disposed between the driven arm body and the main rod module, so that the driven arm body has a tendency to open outward, which can effectively ensure that the measurement surface of the acquisition assembly fits parallel to the wellbore wall surface, thereby significantly reducing the possibility of mud intrusion into the measurement fitting surface and improving the quality and reliability of the micro-resistivity imaging logging.
[0020] Optionally, the balance module includes an oil tank body, a balance piston, a tapered plug, a self-sealing valve and an oil tank fiberglass. The oil tank body is disposed on the main rod module and is close to the power drive module. The oil tank fiberglass is sleeved outside the oil tank body. A chamber is opened in the oil tank body. The balance piston is movably disposed in the chamber and fits with the inner wall of the chamber. The tapered plug is disposed at one end of the oil tank body away from the power drive module. The self-sealing valve is disposed on the oil tank body and is close to the power drive module. When the oil tank body is docked with the power drive module, the self-sealing valve is opened.
[0021] By adopting the above technical solution, after the oil storage main body is docked with the power drive module, the self-sealing valve opens, enabling the hydraulic oil in the chamber to freely flow between the chamber and the power drive module. When the downhole temperature and pressure increase, the volume of the hydraulic oil expands, and the excess hydraulic oil flows into the oil storage main body, pushing the balance piston deeper into the chamber; conversely, when the temperature and pressure decrease, the volume of the hydraulic oil shrinks, and the hydraulic oil in the oil storage main body flows back to the power drive module, and the balance piston moves in the opposite direction under the action of the external mud pressure. During the whole process, the movement of the balance piston realizes the dynamic adjustment of the hydraulic oil volume, ensuring that the internal hydraulic oil pressure of the power drive module is always balanced with the external mud pressure, thereby preventing the wellbore mud from invading the inside of the power drive module and ensuring the stable operation of the equipment. In addition, the special design of the conical plug not only limits the maximum stroke of the balance piston but also optimizes the downward smoothness of the logging tool in the wellbore, further improving the reliability of the equipment.
[0022] Optionally, an upper joint is connected to one end of the main rod module. The upper joint and the power drive module are respectively arranged on both sides of the electrode arm module, and the upper joint is used to dock with the imaging main measurement line sub-section.
[0023] By adopting the above technical solution, the power drive module is arranged inside the main rod module, and the upper joint and the power drive module are respectively located on both sides of the electrode arm module, which can effectively optimize the structural layout of the whole set of equipment. This design not only shortens the path for the signal of the acquisition component to be transmitted to the imaging data processing sub-section, thereby reducing signal loss and improving the signal-to-noise ratio of the pole bean acquisition signal, but also makes the weight distribution on both sides of the electrode arm module more balanced, enhancing the overall stability of the equipment. During the logging process in highly deviated wells or horizontal wells, such a layout helps to ensure the smooth deployment and retraction of the electrode arm module, avoiding serious inclination of the logging tool along the wellbore axis caused by uneven weight, and thus improving the safety of logging operations and the imaging quality.
[0024] Optionally, the acquisition component includes an electrode connecting sleeve, an acquisition electrode plate, a female connector, and a male connector. One end of the electrode connecting sleeve is hinged to the driven arm, the other end of the electrode connecting sleeve is connected to the acquisition electrode plate, the end of the acquisition electrode plate away from the electrode connecting sleeve is hinged to the power arm, the female connector is arranged inside the electrode connecting sleeve, and the male connector is arranged inside the acquisition electrode plate and is docked with the female connector.
[0025] By adopting the above technical solution, the electrode connection sleeve is hinged to the driven arm and the acquisition plate respectively, and one end of the acquisition plate far from the electrode connection sleeve is hinged to the power arm. This structural design enables the acquisition assembly to flexibly adjust its posture, ensuring that the acquisition plate closely adheres to the wellbore surface, thereby improving the accuracy and quality of micro-resistivity scanning imaging. At the same time, the female connector and the male connector are respectively arranged in the electrode connection sleeve and the acquisition plate and are docked, ensuring the stability and reliability of signal transmission, thereby improving the accuracy and quality of micro-resistivity scanning imaging. This connection method not only simplifies the assembly process but also enhances the stability of the overall structure, enabling the device to maintain a good working state in a complex downhole environment.
[0026] In summary, the present application includes at least one of the following beneficial technical effects: 1. Through the mutual cooperation of the main rod module, the power arm, the driven arm, the acquisition assembly, the support member and the power drive module, the power arm, the driven arm, the acquisition assembly and the main rod module can form an isosceles trapezoid structure, realizing two-way logging of lifting and lowering, meeting the requirements of logging operations in the drill pipe transmission and storage mode, and effectively improving the logging efficiency and operation safety; 2. Through the mutual cooperation of the power arm body, the connecting pin, the power link and the support member, a stable triangular-like support structure is formed between the support member, the power link and the power arm body, thereby significantly enhancing and stabilizing the pushing force of the electrode arm module, ensuring that the measurement surface of the acquisition assembly can be more parallel and closely adhered to the wellbore surface, further reducing the possibility of mud intrusion into the measurement adhesion surface, and thus improving the quality of micro-resistivity imaging and the reliability of logging; 3. By arranging a combined structure of a spring, a leaf spring and an upper torsion spring between the driven arm body and the main rod module, the driven arm body has a tendency to open outwards, thereby effectively ensuring that the measurement surface of the acquisition assembly is parallel and adhered to the wellbore surface, and thus significantly reducing the possibility of mud intrusion into the measurement adhesion surface, improving the quality and reliability of micro-resistivity imaging logging; 4. By arranging the upper joint and the power drive module on both sides of the electrode arm module respectively, not only the path for the acquisition assembly signal to be transmitted to the imaging main measurement line short joint is shortened, signal loss is reduced, and the signal-to-noise ratio of the pole bean acquisition signal is improved, but also the weight distribution on both sides of the electrode arm module is more balanced, which helps the electrode arm module to be smoothly deployed and retracted in a highly deviated well or a horizontal well, avoiding serious inclination of the logging instrument along the wellbore axis due to uneven weight, and thus improving the logging operation safety and imaging quality. BRIEF DESCRIPTION OF THE DRAWINGS
[0027] Figure 1 is the overall structural schematic diagram of a micro-resistivity scanning imager that can be lowered for logging in an embodiment of the present application.
[0028] Figure 2It is a partial structural schematic diagram when a downhole-measurable micro-resistivity scanning imager conducts well logging in an embodiment of the present application.
[0029] Figure 3 It is an exploded structural schematic diagram of the driven arm in an embodiment of the present application.
[0030] Figure 4 It is an exploded structural schematic diagram of the acquisition component in an embodiment of the present application.
[0031] Figure 5 It is a partial structural schematic diagram of the power arm and the power drive module in an embodiment of the present application.
[0032] Figure 6 It is an exploded structural schematic diagram of the power arm in an embodiment of the present application.
[0033] Figure 7 It is a cross-sectional view of the balance module in an embodiment of the present application.
[0034] Explanation of reference numerals: 1. Main rod module; 11. Dynamic seal sleeve; 2. Electrode arm module; 21. Power arm; 211. Power arm body; 2111. Lower torsion spring; 2112. Power shaft pin; 2113. Roller; 212. Connecting pin; 213. Power connecting rod; 214. Support member; 2141. Chute; 22. Driven arm; 221. Driven arm body; 2211. Upper connecting block; 2212. Pressing plate; 2213. Wear-resistant block; 222. Elastic member; 2221. Pouting spring; 2222. Leaf spring; 2223. Upper torsion spring; 23. Acquisition component; 231. Electrode connection sleeve; 2311. Electrode oil filling plug; 232. Acquisition electrode plate; 2321. Electrode housing; 2322. Electrode cover plate; 233. Female head connector; 234. Male head connector; 235. Lower connecting block; 3. Power drive module; 31. Power push rod; 4. Balance module; 41. Oil storage tank body; 411. Chamber; 42. Balance piston; 43. Self-sealing valve; 44. Conical plug; 45. Oil storage tank fiberglass; 5. Upper joint. Detailed implementation manners
[0035] The following further Figure 1-7 describes the present application in detail with reference to the
[0036] An embodiment of the present application discloses a downhole-measurable micro-resistivity scanning imager.
[0037] It should be noted that in the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention.
[0038] Referring to Figure 1 , a micro-resistivity scanning imager that can be measured downward includes a main rod module 1, a plurality of electrode arm modules 2, a power drive module 3, and a balance module 4. Among them, the plurality of electrode arm modules 2 are arranged circumferentially around the main rod module 1, the power drive module 3 and the balance module 4 are respectively arranged on the main rod module 1, and the power drive module 3 is respectively connected to the plurality of electrode arm modules 2, so that the power drive module 3 can drive the plurality of electrode arm modules 2 to open or retract, and further enable the micro-resistivity scanning imager to perform well logging during the lowering process and also during the lifting process, effectively improving the well logging efficiency and operation safety.
[0039] One end of the main rod module 1 is connected with an upper joint 5, and a connector is arranged inside the upper joint 5 for connecting the cables of each part such as the electrode arm module 2 and the power drive module 3 to the main measurement line of the micro-resistivity scanning imager, so as to realize system power supply and signal transmission.
[0040] Referring to Figure 1 and Figure 2 , the electrode arm module 2 includes a power arm 21, a driven arm 22, and a collection component 23. Among them, the collection component 23 is respectively hinged to the power arm 21 and the driven arm 22. One end of the power arm 21 away from the collection component 23 is movably connected to the main rod module 1, one end of the driven arm 22 away from the collection component 23 is hinged to the main rod module 1, and the driven arm 22 is arranged close to the upper joint 5.
[0041] When the plurality of electrode arm modules 2 open, the power arm 21, the driven arm 22, the collection component 23, and the main rod module 1 can form an isosceles trapezoid structure, enabling the micro-resistivity scanning imager to perform well logging during the lowering process and also during the lifting process, and further effectively improving the well logging efficiency.
[0042] Referring to Figure 2 and Figure 3, the follower arm 22 includes a follower arm main body 221 and an elastic member 222. Among them, one end of the follower arm main body 221 is hinged to the main rod module 1, and the other end of the follower arm main body 221 is connected with an upper connection block 2211, and the upper connection block 2211 is hinged to the acquisition component 23, so that the follower arm main body 221 can rotate relative to the acquisition component 23. In other embodiments, the upper connection block 2211 may not be provided, and the follower arm main body 221 may be directly hinged to the acquisition component 23.
[0043] The inside of the follower arm main body 221 is hollow to facilitate the laying of the cables required by the acquisition component 23, and a pressing plate 2212 is detachably connected to the follower arm main body 221. The pressing plate 2212 is used to seal the follower arm main body 221 to protect the internal cables.
[0044] The upper connection block 2211 is connected with a wear-resistant block 2213 through a wear-resistant pin shaft. The wear-resistant block 2213 is located between the upper connection block 2211 and the well wall and is used to reduce the wear when contacting the well wall. In this embodiment, the surface of the wear-resistant block 2213 can be clad with hard alloy to increase the wear resistance of the wear-resistant block 2213.
[0045] The elastic member 222 includes a toggle spring 2221, a leaf spring 2222 and an upper torsion spring 2223. Among them, one end of the toggle spring 2221 is fixedly connected to the follower arm main body 221, and the other end of the toggle spring 2221 is slidably arranged on the main rod module 1. Thus, when the follower arm main body 221 rotates, the toggle spring 2221 can move on the main rod module 1.
[0046] A sliding groove is formed at the bottom of the follower arm main body 221. One end of the leaf spring 2222 is slidably arranged in the sliding groove, the other end of the leaf spring 2222 is fixedly connected to the main rod module 1, and the leaf spring 2222 is arranged close to the toggle spring 2221. The upper torsion spring 2223 is arranged between the upper connection block 2211 and the acquisition component 23.
[0047] Through the combined structure of the toggle spring 2221, the leaf spring 2222 and the upper torsion spring 2223, a stable tension can be applied to the follower arm main body 221 to ensure that the follower arm main body 221 always maintains the best state during the working process, so as to effectively ensure that the measurement surface of the acquisition component 23 is parallel and attached to the well wall surface, thereby significantly reducing the possibility of mud invading the measurement attachment surface and improving the quality and reliability of the micro-resistivity imaging logging.
[0048] Refer to Figure 2 and Figure 4The collection assembly 23 includes an electrode connection sleeve 231, a collection plate 232, a female connector 233, and a male connector 234. One end of the electrode connection sleeve 231 is hinged to the upper connection block 2211, and the other end of the electrode connection sleeve 231 is fixedly connected to the collection plate 232. A lower connection block 235 is provided at the end of the collection plate 232 away from the electrode connection sleeve 231. The lower connection block 235 is hinged to the power arm 21, allowing the collection plate 232 to rotate relative to the power arm 21.
[0049] In other embodiments, the lower connecting block 235 may not be provided, and the collecting plate 232 may be directly hinged to the power arm 21 .
[0050] A cable is provided in the electrode connecting sleeve 231, and the female connector 233 is installed in the electrode connecting sleeve 231 and connected to the cable. Electrode oil filling plugs 2311 are respectively installed on both sides of the electrode connecting sleeve 231 to facilitate the injection of oil or silicone grease into the electrode connecting sleeve 231, thereby playing the role of insulation and protection of the cable.
[0051] Reference Figure 4 In this embodiment, the collection plate 232 includes an electrode housing 2321, an electrode cover 2322, and a pole bean signal collection module (not shown). The electrode housing 2321 and the electrode cover 2322 are fixedly connected, and the pole bean signal collection module is installed between the electrode housing 2321 and the electrode cover 2322 to collect signals as the microresistivity scanning imager moves along the wellbore.
[0052] It should be noted that, in the embodiment of the present application, the electrode shell 2321 and the electrode cover plate 2322 cooperate with each other and can withstand a temperature of 230° C. and an external pressure of 210 MPa.
[0053] Reference Figure 1 and Figure 4 The male connector 234 is installed in the electrode housing 2321 and is electrically connected to the pole bean signal acquisition module, and the male connector 234 is used to connect with the female connector 233, so as to facilitate the power supply to the pole bean signal acquisition module and make the signal data collected by the pole bean signal acquisition module pass through the male connector 234, the female connector 233, the slave arm 22 (refer to Figure 2 ) and the main rod module 1 are transmitted to the upper connector 5, and finally transmitted to the data processing board in the imaging main circuit through the cable in the upper connector 5.
[0054] Reference Figure 1 and Figure 5, the power arm 21 includes a power arm main body 211, a connecting pin 212 and a power connecting rod 213. Among them, one end of the power arm main body 211 is hinged to the lower connecting block 235, and the other end is slidably connected to the main rod module 1 and hinged to the power connecting rod 213. The end of the power connecting rod 213 far from the power arm main body 211 is connected to the power driving module 3. Thus, when the power driving module 3 drives the power arm main body 211 to move through the power connecting rod 213, the power arm main body 211 can drive the acquisition electrode plate 232 (refer to Figure 4 ) to move, so as to realize the opening of multiple electrode arm modules 2.
[0055] In this embodiment, the power arm main body 211 can be made of high-strength alloy steel to ensure its strength and wear resistance in high-pressure and high-temperature environments.
[0056] Refer to Figure 2 and Figure 6 , a lower torsion spring 2111 is arranged between the power arm main body 211 and the lower connecting block 235. The lower torsion spring 2111 can apply an outward tension to the power arm main body 211, so that the acquisition assembly 23 can maintain a stable posture during the pushing process, and avoid the influence of unstable factors brought by the movement of the power arm main body 211 on the measurement accuracy.
[0057] A power shaft pin 2112 is installed at one end of the power arm main body 211 close to the power connecting rod 213. The power shaft pin 2112 is rotatably connected to the power connecting rod 213. A roller 2113 is installed on the power shaft pin 2112. The roller 2113 is in rolling connection with the main rod module 1. Thus, it is convenient to convert the sliding friction of the power arm main body 211 into rolling friction by using the roller 2113, so that the movement of the power arm main body 211 on the main rod module 1 is smoother, effectively reducing the energy loss during the power transmission process.
[0058] The connecting pin 212 is installed on the power arm main body 211 and is arranged close to the lower connecting block 235. A support member 214 is hinged to the main rod module 1. The support member 214 is arranged close to the power arm main body 211, and a chute 2141 is opened along the length direction of the end of the support member 214 far from the main rod module 1. The connecting pin 212 is slidably inserted into the chute 2141. This structural design enables the power arm main body 211 to maintain stability during movement, and at the same time, through the cooperation of the chute 2141 of the support member 214 and the connecting pin 212, the effective support of the power arm 21 is realized, enhancing the stability of the power arm 21.
[0059] When the power link 213 moves linearly, the power link 213 can drive the rotation of the power arm body 211, and the power arm body 211 can drive the rotation of the support member 214 through the connecting pin 212, so that a triangular support structure is formed among the support member 214, the power link 213 and the power arm body 211, thereby significantly improving the stability after the opening of multiple electrode arm modules 2, ensuring that the measurement surface of the acquisition electrode plate 232 can be more parallel and closely attached to the wellbore surface, further reducing the possibility of mud intrusion into the measurement attachment surface, and then improving the quality of micro-resistivity imaging and the reliability of well logging. This structural optimization effectively improves the ability of the electrode arm module 2 to pass through complex wellbore environments during well logging, especially performing well in highly deviated wells or horizontal wells.
[0060] Refer to Figure 1 , the power drive module 3 is installed inside the main rod module 1 and is located below the electrode arm module 2. On the one hand, this enables the electrode arm module 2 to be closer to the upper joint 5, shortening the signal transmission path, reducing signal loss, and improving the signal-to-noise ratio of the pole bean signal; on the other hand, the upper joint 5 and the power drive module 3 are distributed on the upper and lower sides of the electrode arm module 2, balancing the weights borne on both sides of the electrode arm module 2 and enhancing the overall stability and operation safety of the equipment.
[0061] Refer to Figure 1 and Figure 6 , the power drive module 3 includes a driving member (not shown in the figure) and a power push rod 31. Among them, the driving member is installed inside the main rod module 1, the power push rod 31 is coaxially arranged inside the main rod module 1 and is fixedly connected to the driving member, and the number of power push rods 31 is equal to and corresponds to the number of power links 213 one by one, so that the driving member can synchronously drive multiple power links 213 to move linearly through the power push rods 31, so that a triangular support structure is formed among the support member 214, the power link 213, the power push rod 31 and the power arm body 211.
[0062] It should be noted that the specific structure of the driving member belongs to conventional technical means for those skilled in the art, so it will not be elaborated too much in the embodiments of this application.
[0063] A dynamic seal sleeve 11 is installed inside the main rod module 1. The number of dynamic seal sleeves 11 is equal to the number of power links 213, and each power push rod 31 passes through the dynamic seal sleeve 11. On the one hand, the dynamic seal sleeve 11 can be used to straighten the power push rod 31 to ensure the stability and accuracy of the movement of the power push rod 31 and the power link 213; on the other hand, it effectively isolates the liquid inside and outside the main rod module 1, avoiding external mud from entering the inside and affecting the normal operation of the equipment.
[0064] Refer to Figure 1 and Figure 7, the balance module 4 is installed on the main rod module 1 and is located on the side of the power drive module 3 away from the electrode arm module 2. The balance module 4 includes an oil tank body 41, a balance piston 42, a self-sealing valve 43, a tapered plug 44, and an oil tank fiberglass 45.
[0065] The oil tank body 41 is installed on the main rod module 1 and is arranged close to the power drive module 3. A chamber 411 is formed in the oil tank body 41 for storing hydraulic oil. The self-sealing valve 43 is installed on the oil tank body 41 and is arranged close to the power drive module 3.
[0066] When the oil tank body 41 is placed alone, the self-sealing valve 43 is in a closed state. When the oil tank body 41 is docked with the power drive module 3, the self-sealing valve 43 opens, enabling the hydraulic oil in the chamber 411 to flow freely between the chamber 411 and the power drive module 3.
[0067] The balance piston 42 is movably arranged in the chamber 411 and fits against the inner wall of the chamber 411. Thus, when the downhole temperature and pressure increase, the volume of the hydraulic oil expands, and the excess hydraulic oil flows into the oil tank body 41, pushing the balance piston 42 to move deeper into the chamber 411. Conversely, when the temperature and pressure decrease, the volume of the hydraulic oil contracts, and the hydraulic oil in the oil tank body 41 flows back to the power drive module 3, and the balance piston 42 moves in the opposite direction under the action of the external mud pressure. During the whole process, the movement of the balance piston 42 realizes the dynamic adjustment of the hydraulic oil volume, ensuring that the internal hydraulic oil pressure of the power drive module 3 is always balanced with the external mud pressure, thereby avoiding the intrusion of wellbore mud into the interior of the power drive module 3 and ensuring the stable operation of the equipment.
[0068] The oil tank fiberglass 45 is sleeved outside the oil tank body 41, and the oil tank fiberglass 45 can play the roles of insulation and protection, thus greatly reducing the possibility of the emission current leaking from the oil tank body 41 to the wellbore mud.
[0069] The tapered plug 44 is installed at one end of the oil tank body 41 away from the power drive module 3 and extends into the chamber 411. Thus, on the one hand, the tapered plug 44 can be used to limit the maximum stroke of the balance piston 42, and on the other hand, it optimizes the downward fluency of the logging tool in the wellbore, further improving the reliability of the equipment.
[0070] The implementation principle of a micro-resistivity scanning imager with downward measurement in an embodiment of the present application is as follows: When well logging is required, first start the driving member. The driving member drives the power push rod 31 to move linearly. The power push rod 31 pushes the power connecting rod 213 to move, so that the power connecting rod 213 pushes the power arm main body 211 to move. The power arm main body 211 drives the support member 214 to rotate and drives the acquisition electrode plate 232 to move through the lower connecting block 235. The acquisition electrode plate 232 drives the driven arm main body 221 to rotate through the upper connecting block 2211, so that the power arm 21, the driven arm 22, the acquisition component 23 and the main rod module 1 form an isosceles trapezoid structure, so that the measurement surface of the acquisition electrode plate 232 is parallel to and fits against the wellbore surface. Then, the micro-resistivity scanning imager is slid downward or upward along the wellhead at a certain speed to complete signal acquisition.
[0071] During this process, the power drive module 3 locks the thrust, and the buckling spring 2221, the leaf spring 2222 and the upper torsion spring 2223 apply an outward tension to the driven arm main body 221, and the lower torsion spring 2111 applies an outward tension to the power arm main body 211, so that the acquisition electrode plate 232 stably maintains a certain pressure on the wellbore, ensuring the accuracy of the measurement results.
[0072] When the well logging is completed, the driving member drives the power push rod 31 to move in the reverse direction. The power push rod 31 drives the power arm main body 211, the driven arm main body 221 and the acquisition electrode plate 232 to move in sequence through the power connecting rod 213, and overcomes the acting forces applied by the buckling spring 2221, the leaf spring 2222, the upper torsion spring 2223 and the lower torsion spring 2111 to retract the multiple electrode arm modules 2, so as to facilitate pulling the micro-resistivity scanning imager to the ground.
[0073] The above are all the preferred embodiments of the present application, and the protection scope of the present application is not limited thereby. Therefore, all equivalent changes made according to the structure, shape and principle of the present application should be covered within the protection scope of the present application.
Claims
1. A downhole measurable micro-resistivity scanning imager, characterized in that, Comprising: A main rod module (1); A plurality of electrode arm modules (2) arranged circumferentially around the main rod module (1). The electrode arm module (2) includes a power arm (21), a driven arm (22), and a collection component (23). The collection component (23) is respectively hinged to the power arm (21) and the driven arm (22). One end of the driven arm (22) away from the collection component (23) is hinged to the main rod module (1). One end of the power arm (21) away from the collection component (23) is movably connected to the main rod module (1). A support member (214) is movably connected between the power arm (21) and the main rod module (1); A power drive module (3) arranged inside the main rod module (1) and connected to a plurality of the power arms (21). The power drive module (3) is used to drive the plurality of power arms (21) to move; A balance module (4) arranged on the main rod module (1). The balance module (4) is used to balance the pressure of the liquid inside the main rod module (1) and the external mud.
2. The measurable micro-resistivity scanning imager according to claim 1, wherein: The power arm (21) includes a power arm body (211), a connecting pin (212), and a power link (213). One end of the power arm body (211) is hinged to the collection component (23). The other end of the power arm body (211) is slidably connected to the main rod module (1) and hinged to the power link (213). One end of the power link (213) away from the power arm body (211) is connected to the power drive module (3). The connecting pin (212) is arranged on the power arm body (211). One end of the support member (214) is hinged to the main rod module (1). A chute (2141) is provided along the length direction of the other end of the support member (214). The connecting pin (212) is slidably inserted into the chute (2141).
3. The measurable micro-resistivity scanning imager according to claim 2, characterized in that: A power shaft pin (2112) is arranged on the power arm body (211). The power shaft pin (2112) is rotatably connected to the power link (213). A roller (2113) is arranged on the power shaft pin (2112). The roller (2113) is in rolling connection with the main rod module (1).
4. The measurable micro-resistivity scanning imager according to claim 2, wherein: A lower torsion spring (2111) is arranged between the power arm body (211) and the collection component (23).
5. The measurable micro-resistivity scanning imager according to claim 2, wherein: The power drive module (3) includes a driving member and a power push rod (31). The driving member is arranged inside the main rod module (1). The power push rod (31) is coaxially arranged inside the main rod module (1) and connected to the driving member. A dynamic seal sleeve (11) is arranged inside the main rod module (1). One end of the power push rod (31) away from the driving member passes through the dynamic seal sleeve (11) and is connected to the power link (213). The driving member is used to drive the power push rod (31) to move linearly.
6. The measurable micro-resistivity scanning imager according to claim 1, characterized in that: The driven arm (22) includes a driven arm body (221) and an elastic member (222). One end of the driven arm body (221) is hinged to the acquisition assembly (23), and the other end of the driven arm body (221) is hinged to the main rod module (1). The elastic member (222) is disposed between the driven arm body (221) and the main rod module (1), and the elastic member (222) is used to drive the driven arm body (221) to open.
7. The micro-resistivity scanning imager capable of downward measurement according to claim 6, characterized in that: The elastic member (222) includes a toggle spring (2221), a leaf spring (2222), and an upper torsion spring (2223). One end of the toggle spring (2221) is connected to the driven arm body (221), and the other end of the toggle spring (2221) is movably disposed on the main rod module (1). One end of the leaf spring (2222) is slidably disposed on the driven arm body (221), and the other end of the leaf spring (2222) is disposed on the main rod module (1). The upper torsion spring (2223) is disposed between the driven arm body (221) and the acquisition assembly (23).
8. The measurable micro-resistivity scanning imager according to claim 1, characterized in that: The balance module (4) includes an oil tank body (41), a balance piston (42), a tapered plug (44), a self-sealing valve (43), and an oil tank fiberglass (45). The oil tank body (41) is disposed on the main rod module (1) and is close to the power drive module (3). The oil tank fiberglass (45) is sleeved outside the oil tank body (41). A chamber (411) is defined in the oil tank body (41). The balance piston (42) is movably disposed in the chamber (411) and is in contact with the inner wall of the chamber (411). The tapered plug (44) is disposed at one end of the oil tank body (41) away from the power drive module (3). The self-sealing valve (43) is disposed on the oil tank body (41) and is close to the power drive module (3). When the oil tank body (41) is docked with the power drive module (3), the self-sealing valve (43) is opened.
9. The measurable micro-resistivity scanning imager according to claim 1, characterized in that: One end of the main rod module (1) is connected with an upper joint (5). The upper joint (5) and the power drive module (3) are respectively disposed on both sides of the electrode arm module (2). The upper joint (5) is used to dock with the imaging main measurement line sub-section.
10. The measurable micro-resistivity scanning imager according to claim 1, characterized in that: The acquisition assembly (23) includes an electrode connection sleeve (231), acquisition electrodes (232), a female connector (233), and a male connector (234). One end of the electrode connection sleeve (231) is hinged to the driven arm (22), and the other end of the electrode connection sleeve (231) is connected to the acquisition electrodes (232). One end of the acquisition electrodes (232) away from the electrode connection sleeve (231) is hinged to the power arm (21). The female connector (233) is disposed in the electrode connection sleeve (231), and the male connector (234) is disposed in the acquisition electrodes (232) and is docked with the female connector (233).