Optical fiber multi-parameter logging device

Abstract

The application discloses a kind of optical fiber multi-parameter logging devices, it is related to marine engineering equipment technical field, cable winch, logging cable, guide wheel and logging unit for downhole optical scanning and parameter measurement;Cable winch is used to wind and release logging cable;One end of the logging cable is connected to the cable winch, and the other end is guided by the guide wheel and connected to the logging unit;The logging unit is provided with a gasbag one sealed on the outside of the borescope and a gasbag two for fixing the detection position, which can isolate drilling fluid by inflating to achieve accurate detection and fixation of the detection position and maintain pressure balance;It can realize the technical effects of improving the stability of fixation, improving environmental adaptability, reducing signal interference and flexibly maintaining the pressure balance in the well.

Description

Technical Field

[0001] This invention relates to the field of marine engineering equipment technology, and in particular to a fiber optic multi-parameter logging device. Background Technology

[0002] Seabed drilling is an engineering technology for the direct exploration and development of oil and gas resources on the seabed. It is mainly used for resource extraction in deep sea (usually referring to water depths exceeding 300 meters) and ultra-deep sea (water depths exceeding 1500 meters). Its core objective is to obtain oil and gas resources by drilling wells in the seabed strata through complex underwater operating systems.

[0003] Seabed drilling systems mainly rely on three types of platforms: floating drilling vessels, semi-submersible drilling platforms, and floating production platforms. These platforms are mainly connected to subsea blowout preventers via risers to form a closed-loop system, ensuring drilling fluid circulation and well control safety. In the field of deep-sea oil drilling, logging technology is a key link in ensuring wellbore safety and production efficiency.

[0004] Currently, well logging primarily relies on mechanical fixing mechanisms, such as expanding nickel alloy sheets to adhere tightly to the wellbore for positioning. While this improves detection efficiency to some extent, it presents challenges in the high-pressure environment of the deep sea. Mechanical fixing components are prone to elastic rebound under high pressure, leading to a decrease in fixing force. This necessitates repeated manual adjustments, increasing operational complexity and time costs. Furthermore, wellbore walls are often irregular (e.g., narrow or highly irregular), unable to adapt to contour changes, easily creating blind spots and affecting data integrity. Additionally, after drilling on the seabed, a large amount of drilling fluid (including oil-based or synthetic-based mud) directly contacts optical components, causing light signal scattering or absorption, reducing the image signal-to-noise ratio. Moreover, the high-pressure fluctuations in the deep sea (such as those caused by drilling fluid circulation) may lead to creep or stress concentration in the fixing components, making it difficult to maintain pressure balance within the well. Summary of the Invention

[0005] This application provides a fiber optic multi-parameter logging device that solves the technical problems of low fixed stability, poor environmental adaptability, severe signal interference, and inability to flexibly maintain well pressure balance in the prior art. It achieves the technical effects of improved fixed stability, improved environmental adaptability, reduced signal interference, and flexible maintenance of well pressure balance.

[0006] This application provides a fiber optic multi-parameter logging device, including a cable winch, a logging cable, a guide wheel, and a logging unit for downhole optical scanning and parameter measurement;

[0007] The cable winch is used to wind and release the logging cable; one end of the logging cable is connected to the cable winch, and the other end is guided by a guide wheel and connected to the logging unit; the logging unit has an airbag one that is sealed and covered on the outside of the pipe endoscope and an airbag two for fixing the detection position. By inflating, the drilling fluid is isolated so as to perform accurate detection, fix the detection position and maintain pressure balance.

[0008] Furthermore, the logging unit includes a movable cylinder, a glass cover, a pipe endoscope, an airbag one, an electric telescopic rod one, a fixed column, an electric telescopic rod two, and an airbag two;

[0009] The movable cylinder is a cylindrical structure with a transparent glass cover fixed inside to protect the endoscope. The endoscope is rotatably connected inside the glass cover via a drive motor and is used to rotate and scan the well wall. An airbag is placed on the outside of the glass cover and expands to fit the well wall, forming an isolation space. The movable cylinder is slidably connected to the top of the fixed column via an electric telescopic rod. An electric telescopic rod is slidably connected to the bottom of the fixed column. The fixed column is a columnar structure with a connecting ring 1 fixed at its lower end. The electric telescopic rod 2 has a connecting ring 2 fixed at its lower end. The upper and lower ends of the airbag 2 are fixed and sealed to the connecting ring 1 and connecting ring 2, respectively, and cover the outside of the fixed column and the electric telescopic rod 2, and are used to fix the detection position by expanding.

[0010] Furthermore, a miniature air pump is installed inside the fixed column. The miniature air pump is connected to airbag one and airbag two through a miniature pipe and is used to provide gas to the logging unit to achieve fixed detection position.

[0011] Furthermore, the airbag has a ring-shaped structure when inflated, and is made of a highly transparent film to isolate drilling fluid. Its surface is coated with a fluororubber coating to flexibly fit the well wall after inflation, forming a clean observation window and reducing light signal scattering.

[0012] Furthermore, the second airbag includes two airbag structures: a secondary airbag and a primary airbag. The overall structure of the second airbag is a three-layer structure from top to bottom: secondary airbag-primary airbag-secondary airbag.

[0013] Furthermore, the internal space of the main airbag is evenly divided into multiple cavities along the circumference, and the inner wall of each cavity is filled with an iron powder mixture; a fixing ring is fixed to the outside of the fixing column by a connecting frame, the fixing ring is sleeved on the outside of the electric telescopic rod, and multiple electromagnets are fixed along its side wall circumferentially, the electromagnets correspond one-to-one with the cavity positions, and attract the iron powder mixture through magnetic attraction to adjust the overall shape of the main airbag to adapt to the narrow or irregular wellbore sidewall.

[0014] Furthermore, each cavity in the main airbag has a pressure sensor embedded in its outer wall. The pressure sensors are distributed in a dot matrix on the outer wall of the corresponding cavity to detect the pressure information of each cavity in the expansion state.

[0015] Furthermore, a tension sensor is fixed to the telescopic end of the electric telescopic rod 2. The tension sensor is a fiber optic tension sensor used to sense the axial tension transmitted by the main airbag. By controlling the vertical movement distance of the electric telescopic rod 2, the main airbag is squeezed to achieve pressure compensation and fine adjustment of the fixing force.

[0016] Furthermore, the pressure sensor, tension sensor, electromagnet, micro air pump, and valves of each micro pipeline are all controlled by an external control system. By feeding back pressure data from the pressure sensor and tension sensor, the overall expansion state of the airbag II and the magnetic force of the electromagnet are actively regulated to maintain the pressure balance inside the well.

[0017] Furthermore, the cavity of the main airbag is initially filled with a fixed amount of gas. During the entire process of fixing the position, a fixed amount of gas is first pre-filled into the internal space between the second airbag, the fixed column, and the second electric telescopic rod, so that the second airbag is pre-inflated. During the gradual expansion process, the on / off state and magnetic force of the electromagnets at different positions are controlled according to the monitoring data of the pressure sensors at each point, so as to change the overall shape of the second airbag to adapt to the shape of the well wall. Then, gas is inflated into the two auxiliary airbags to stabilize the overall expansion state of the second airbag. Then, the vertical movement distance of the second electric telescopic rod is further controlled to compress the main airbag, thereby compensating for the compression force on the well wall and improving the stability after fixing.

[0018] One or more technical solutions provided in this application have at least the following technical effects or advantages:

[0019] By setting up a transparent airbag that covers the outside of the endoscope, drilling fluid isolation is achieved to solve the signal interference problem; the multi-layer structure of the second airbag and the optimized inflation process solve the fixation stability problem; the electromagnetic shape self-adaptation of the main airbag solves the environmental adaptability problem; and the sensor network and active control solve the pressure balance problem. This effectively solves the technical problems of low fixation stability, poor environmental adaptability, severe signal interference, and inability to flexibly maintain the pressure balance in the well in existing technologies, and achieves the technical effects of improved fixation stability, improved environmental adaptability, reduced signal interference, and flexible maintenance of the pressure balance in the well. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the overall structure of a fiber optic multi-parameter logging device according to the present invention.

[0021] Figure 2This is a schematic diagram of the logging unit of the fiber optic multi-parameter logging device of the present invention in its initial state.

[0022] Figure 3 This is a schematic diagram of the logging unit of a fiber optic multi-parameter logging device of the present invention in the state of gas expansion.

[0023] Figure 4 This invention relates to a fiber optic multi-parameter logging device. Figure 3 Full sectional view along the AA direction.

[0024] Figure 5 This is a partial half-section schematic diagram of the logging unit of a fiber optic multi-parameter logging device according to the present invention.

[0025] Figure 6 This is a partial structural cross-sectional view of the airbag and electric telescopic rod of the fiber optic multi-parameter logging device of the present invention.

[0026] Figure 7 This is a schematic diagram of the structure of the main airbag of the fiber optic multi-parameter logging device of the present invention, which adjusts the overall shape of the airbag II under magnetic attraction to adapt to the irregular shape of the wellbore sidewall.

[0027] In the diagram: 100, cable winch; 101, logging cable; 110, guide wheel; 120, miniature air pump; 200, logging unit; 210, movable cylinder; 211, glass cover; 212, pipe endoscope; 220, airbag one; 230, electric telescopic rod one; 240, fixed column; 241, connecting ring one; 250, electric telescopic rod two; 251, connecting ring two; 260, airbag two; 261, auxiliary airbag; 262, main airbag; 263, iron powder mixture; 270, connecting frame; 271, fixed ring; 272, electromagnet; 280, pressure sensor. Detailed Implementation

[0028] To facilitate understanding of the present invention, a more complete description of this application will be given below with reference to the accompanying drawings, which illustrate preferred embodiments of the invention. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to enable a more thorough and complete understanding of the disclosure of the present invention.

[0029] It should be noted that the terms "vertical," "horizontal," "up," "down," "left," "right," and similar expressions used in this article are for illustrative purposes only and do not represent the only possible implementation.

[0030] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains; the terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to limit the invention; the term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0031] Please see Figure 1 This is a schematic diagram of the overall structure of a fiber optic multi-parameter logging device according to the present invention. The fiber optic multi-parameter logging device of this application solves the signal interference problem by setting a transparent airbag 220 that covers the outside of the endoscope 212, thereby isolating the drilling fluid; solving the stability problem by using the multi-layer structure and optimized inflation process of the second airbag 260; solving the environmental adaptability problem by using the electromagnetic adaptive shape of the main airbag 262; and solving the pressure balance problem by using a sensor network and active control. This achieves the technical effects of improved stability, enhanced environmental adaptability, reduced signal interference, and flexible maintenance of well pressure balance.

[0032] Example 1: As Figures 1 to 6 As shown, this application discloses a fiber optic multi-parameter logging device, which includes a cable winch 100, a logging cable 101, a guide wheel 110, and a logging unit 200 for downhole optical scanning and parameter measurement.

[0033] The cable winch 100 is used to wind and release the logging cable 101; one end of the logging cable 101 is connected to the cable winch 100, and the other end is guided by the guide wheel 110 and connected to the logging unit 200.

[0034] The logging unit 200 has an airbag 220 that is sealed and covered on the outside of the endoscope 212 and an airbag 260 for fixing the detection position. By inflating, the drilling fluid is isolated so as to make accurate detection, fix the detection position and maintain pressure balance.

[0035] like Figures 2 to 5 As shown, the logging unit 200 includes a movable cylinder 210, a glass cover 211, a pipe endoscope 212, an airbag 220, an electric telescopic rod 230, a fixed column 240, an electric telescopic rod 250, and an airbag 260.

[0036] The movable cylinder 210 has a cylindrical structure, inside which a glass cover 211 is fixed. The glass cover 211 is made of transparent material and is used to protect the endoscope 212. The endoscope 212 is rotatably connected inside the glass cover 211 by a drive motor and is used to rotate and scan the well wall. The first airbag 220 covers the outside of the glass cover 211 and expands to fit the well wall by inflation, forming an isolation space. The movable cylinder 210 is slidably connected above the fixed column 240 by an electric telescopic rod 230. The second electric telescopic rod 250 is slidably connected below the fixed column 240. The fixed column 240 has a columnar structure and a connecting ring 241 is fixed to its lower end. The second electric telescopic rod 250 has a connecting ring 251 fixed to its lower end. The upper and lower ends of the second airbag 260 are fixed and sealed to the connecting ring 241 and the second connecting ring 251, respectively, and cover the outside of the fixed column 240 and the second electric telescopic rod 250, and are used to fix the detection position by inflation.

[0037] like Figure 5 and 6 As shown, a miniature air pump 120 is installed inside the fixed column 240. The miniature air pump 120 is connected to air bag 1 220 and air bag 260 through a miniature pipe, and is used to provide gas to the logging unit 200 to achieve fixed detection position.

[0038] The airbag 220 has a ring-shaped structure when inflated. It is made of a high-transparency film to isolate drilling fluid, and its surface is coated with a fluororubber coating to flexibly fit the well wall after inflation, forming a clean observation window and reducing light signal scattering.

[0039] This application constructs an airbag 220 that covers the outside of the endoscope 212 and is connected to a miniature air pump 120 to form an inflation isolation system. The airbag is made of a high-transparency film coated with a fluororubber coating, which has a self-cleaning function. It can form a sealed isolation space outside the endoscope 212, physically preventing drilling fluid (including oil-based mud) from directly contacting the optical elements, reducing impurity adhesion and bubble interference. By creating a "clean observation window" through isolation, the attenuation of light signals is reduced, and the detection accuracy is improved.

[0040] like Figures 3 to 7 As shown, the second airbag 260 includes two airbag structures, namely the secondary airbag 261 and the main airbag 262. The overall structure of the second airbag 260 is a three-layer structure from top to bottom: secondary airbag 261-main airbag 262-secondary airbag 261.

[0041] The internal space of the main airbag 262 is evenly divided into multiple cavities along the circumference, and the inner wall of each cavity is filled with iron powder mixture 263. The fixing ring 271 is fixed to the outside of the fixing column 240 through the connecting frame 270. The fixing ring 271 is sleeved on the outside of the electric telescopic rod 250, and multiple electromagnets 272 are fixed along its side wall circumferentially. The electromagnets 272 correspond one-to-one with the cavity positions and attract the iron powder mixture 263 through magnetic attraction to adjust the overall shape of the main airbag 262 to adapt to the narrow or irregular wellbore sidewall.

[0042] like Figures 3 to 7 As shown, each cavity in the main airbag 262 has a pressure sensor 280 embedded in its outer wall. The pressure sensors 280 are distributed in a dot matrix on the outer wall of the corresponding cavity to detect the pressure information of each cavity in the expansion state.

[0043] A tension sensor is fixed to the telescopic end of the electric telescopic rod 250. The tension sensor is a fiber optic tension sensor used to sense the axial tension transmitted by the main airbag 262. By controlling the vertical movement distance of the electric telescopic rod 250, the main airbag 262 is squeezed to achieve pressure compensation and fine adjustment of the fixing force.

[0044] The pressure sensor 280, along with the tension sensor, electromagnet 272, micro air pump 120, and valves in each micro-pipeline, are all controlled by an external control system. By feeding back pressure data through the pressure sensor 280 and tension sensor, the overall expansion state of the second airbag 260 and the magnetic force of the electromagnet 272 are actively adjusted to maintain the pressure balance inside the well.

[0045] The cavity of the main airbag 262 is initially filled with a fixed amount of gas. During the entire process of fixing the position, a fixed amount of gas is first pre-filled into the internal space between the second airbag 260, the fixed column 240, and the second electric telescopic rod 250, so that the second airbag 260 is pre-inflated. During the gradual expansion process, according to the detection data of the pressure sensor 280 at each point, the on / off state and magnetic force of the electromagnet 272 at different positions are controlled to change the overall shape of the second airbag 260 to adapt to the shape of the well wall. Then, gas is inflated into the two auxiliary airbags 261 to stabilize the overall expansion state of the second airbag 260. Then, the vertical movement distance of the second electric telescopic rod 250 is further controlled to compress the main airbag 262, thereby achieving compression compensation of the well wall to improve the stability after fixing.

[0046] This application addresses environmental adaptability by implementing an electromagnetic shape adaptive mechanism for the main airbag 262. The main airbag 262 is divided into multiple cavities along its circumference and filled with an iron powder mixture 263. A control system adjusts the on / off state and magnetic force of the electromagnet 272 based on data from the pressure sensor 280. The electromagnet 272 generates magnetic attraction, drawing the iron powder mixture 263 into the airbag. This causes localized deformation of the cavities at different locations within the main airbag 262, thereby adjusting the overall contour to conform to irregular well walls (such as narrow or uneven areas), thus solving the problem of insufficient conformity due to the inability to flexibly adapt to irregularly shaped well walls.

[0047] This application utilizes a three-layer structure of airbag 260 (auxiliary airbag 261-main airbag 262-auxiliary airbag 261), combined with step-by-step inflation by a micro air pump 120 and linkage with an electric telescopic rod 250, to improve fixation stability. First, pre-inflation causes airbag 260 to initially expand and conform to the well wall. Then, based on data from pressure sensor 280, electromagnet 272 is controlled to attract iron powder mixture 263 to adjust the shape of main airbag 262. Subsequently, auxiliary airbag 261 is inflated to stabilize the state. Finally, the electric telescopic rod 250 moves vertically to compress main airbag 262 for mechanical compensation. This process provides uniform pressure distribution through pneumatic expansion, avoiding stress concentration. The three-layer structure enhances toughness to resist creep and rebound under deep-sea high pressure, achieving uniform pressure distribution and resisting high-pressure creep, thus reducing the attenuation rate of fixation force.

[0048] This application solves the pressure balance problem by setting up sensors and an active control system. Pressure sensors 280 are embedded in the outer wall of the cavity of the main airbag 262 in a dot matrix pattern. A fiber optic tension sensor is provided at the telescopic end of the electric telescopic rod. These sensors, along with the electromagnet 272 and the micro air pump 120, are integrated through a control system to form a closed-loop feedback process. The pressure sensors 280 detect the pressure distribution of each cavity in real time, and the tension sensor senses the axial tension. Based on the information detected by the sensors, the control system issues commands to first adjust the magnetic force of the electromagnet 272 to balance the shape of the second airbag 260 (i.e., the main airbag 262), then control the movement distance of the second electric telescopic rod 250 to compress the main airbag 262, and finally, the micro air pump 120 fine-tunes the gas volume to achieve an active cycle of "monitoring-adjustment-compensation". This can counteract deep-sea pressure fluctuations (such as 0.1MPa level changes caused by drilling fluid circulation), prevent airbag creep or stress concentration, ensure uniform pressure distribution, and significantly improve operational safety.

[0049] The logging unit 200 is also equipped with a depth counter to monitor the height position and ensure accurate positioning to the target detection depth; the control unit is used to control the coordinated operation of various components of the detection platform, preferably a programmable logic controller; this is prior art and will not be described in detail here.

[0050] In actual operation, the steps of this embodiment are as follows:

[0051] Step 1: Start the cable winch 100 and slowly release the logging cable 101. Guided by the guide wheel 110, the logging unit 200 is driven down the wellbore. The depth counter monitors the position to ensure accurate positioning to the target detection depth (such as a specific layer in the wellbore).

[0052] Step 2: After the logging unit 200 reaches the target depth, a fixed amount of gas is pre-filled into the internal space between the second gasbag 260, the fixed column 240, and the second electric telescopic rod 250, so that the second gasbag 260 initially expands. During the expansion process, the pressure sensor 280 detects the pressure data of each cavity in a dot matrix distribution. The external control system adjusts the on / off state and magnetic force of the electromagnet 272 according to the data, and attracts the iron powder mixture 263 through magnetic attraction, so that the main gasbag 262 is locally deformed to adapt to the well wall morphology (such as narrow or uneven areas).

[0053] Step 3: After the main airbag 262 is shaped, air is injected into the two auxiliary airbags 261 to stabilize the overall expansion state of the second airbag 260. Furthermore, the external control system can also integrate the data from the pressure sensor 280 and the tension sensor to dynamically adjust the gas volume of the micro air pump 120 and the magnetic force of the electromagnet 272, controlling the vertical movement of the second electric telescopic rod 250. The axial tension data fed back by the tension sensor (fiber optic type) at its telescopic end is used to compress the main airbag 262 to achieve pressure compensation. At the same time, it can also maintain the pressure balance in the well (such as counteracting the 0.1MPa level fluctuations caused by drilling fluid circulation), improving operational safety.

[0054] Step 4: After the first airbag 220 and the second airbag 260 are fixed in place, the electric telescopic rod 230 can be activated to finely adjust the height of the endoscope 212. Then, the micro air pump 120 is activated to inflate the first airbag 220 through the micro pipe. The first airbag 220 covers the glass cover 211 on the outside of the endoscope 212. After inflation, it expands and flexibly fits the well wall. The drive motor of the endoscope 212 is activated to make it rotate inside the glass cover 211 to perform optical scanning and parameter measurement on the well wall, achieving accurate and stable multi-parameter logging with high data integrity.

[0055] Step 5: After the test is completed, the control system first controls the micro air pump 120 to draw gas from airbag 1 220 and airbag 2 260, so that the logging unit 200 returns to the contracted state; then, the cable winch 100 is started to wind back the logging cable 101 and lift the logging unit 200 away from the wellbore.

[0056] The technical solutions described in the embodiments of this application have at least the following technical effects or advantages:

[0057] This invention solves the technical problems of low fixed stability, poor environmental adaptability, severe signal interference, and inability to flexibly maintain well pressure balance in existing technologies, and achieves the technical effects of improved fixed stability, improved environmental adaptability, reduced signal interference, and flexible maintenance of well pressure balance.

[0058] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. For those skilled in the art, the present invention can have various modifications and variations. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A fiber optic multi-parameter logging device, characterized in that, Includes a cable winch (100), logging cable (101), guide wheel (110), and logging unit (200) for downhole optical scanning and parameter measurement. The cable winch (100) is used to wind and release the logging cable (101); one end of the logging cable (101) is connected to the cable winch (100), and the other end is guided by the guide wheel (110) and connected to the logging unit (200). The logging unit (200) has an airbag one (220) that is sealed and covered on the outside of the endoscope (212) and an airbag two (260) for fixing the detection position. The airbag expands to isolate the drilling fluid so as to make accurate detection and fix the detection position and maintain pressure balance. The logging unit (200) includes a movable cylinder (210), a glass cover (211), a pipe endoscope (212), an airbag (220), an electric telescopic rod (230), a fixed column (240), an electric telescopic rod (250), and an airbag (260). The movable cylinder (210) is a cylindrical structure with a glass cover (211) fixed inside. The glass cover (211) is made of transparent material and is used to protect the endoscope (212). The endoscope (212) is rotatably connected to the glass cover (211) via a drive motor and is used to rotate and scan the well wall. The airbag (220) covers the outside of the glass cover (211) and expands to fit the well wall, forming an isolation space. The movable cylinder (210) is slidably connected to the fixed column (240) via an electric telescopic rod (230). Above; the electric telescopic rod two (250) is slidably connected to the bottom of the fixed column (240); the fixed column (240) is a columnar structure and its lower end is fixed with a connecting ring one (241), the lower end of the electric telescopic rod two (250) is fixed with a connecting ring two (251), the upper end and lower end of the airbag two (260) are fixed and sealed to the connecting ring one (241) and the connecting ring two (251) respectively, and cover the outside of the fixed column (240) and the electric telescopic rod two (250) for fixing the detection position by inflation; The fixed column (240) is equipped with a micro air pump (120), which is connected to air bag one (220) and air bag two (260) through a micro pipe to provide gas to the logging unit (200) to achieve fixed detection position; The airbag (220) has a ring structure when inflated. It is made of a high-transparency film to isolate drilling fluid, and its surface is coated with a fluororubber coating to flexibly fit the well wall after inflation, forming a clean observation window and reducing light signal scattering.

2. The fiber optic multi-parameter logging device as described in claim 1, characterized in that, The second airbag (260) includes two airbag structures, namely the secondary airbag (261) and the main airbag (262). The overall structure of the second airbag (260) is a three-layer structure from top to bottom: secondary airbag (261) - main airbag (262) - secondary airbag (261).

3. The fiber optic multi-parameter logging device as described in claim 2, characterized in that, The internal space of the main airbag (262) is evenly divided into multiple cavities along the circumference, and the inner sidewall of each cavity is filled with iron powder mixture (263). The fixing ring (271) is fixed to the outside of the fixing column (240) through the connecting frame (270). The fixing ring (271) is sleeved on the outside of the electric telescopic rod (250), and multiple electromagnets (272) are fixed along its sidewall circumference. The electromagnets (272) correspond one-to-one with the cavity position and attract the iron powder mixture (263) through magnetic attraction to adjust the overall shape of the main airbag (262) to adapt to the narrow or irregular wellbore sidewall.

4. The fiber optic multi-parameter logging device as described in claim 3, characterized in that, Each cavity in the main airbag (262) has an embedded pressure sensor (280) on its outer wall. The pressure sensors (280) are distributed in a dot matrix on the outer wall of the corresponding cavity to detect the pressure information of each cavity in the expansion state.

5. The fiber optic multi-parameter logging device as described in claim 3, characterized in that, The telescopic end of the electric telescopic rod 2 (250) is fixed with a tension sensor, which is a fiber optic tension sensor used to sense the axial tension transmitted by the main airbag (262). By controlling the vertical movement distance of the electric telescopic rod 2 (250), the main airbag (262) is squeezed to achieve pressure compensation and fine adjustment of the fixing force.

6. The fiber optic multi-parameter logging device as described in claim 4, characterized in that, The pressure sensor (280), tension sensor, electromagnet (272), micro air pump (120), and valves of each micro pipeline are all controlled by an external control system. The pressure sensor (280) and tension sensor provide feedback on pressure data, and actively regulate the overall expansion state of the second airbag (260) and the magnetic force of the electromagnet (272) to maintain the pressure balance in the well.

7. The fiber optic multi-parameter logging device as described in claim 6, characterized in that, The cavity of the main airbag (262) is initially filled with a fixed amount of gas. During the entire process of fixing the position, a fixed amount of gas is first injected into the internal space between the second airbag (260), the fixed column (240), and the second electric telescopic rod (250), so that the second airbag (260) is pre-expanded. During the gradual expansion process, according to the detection data of the pressure sensor (280) at each point, the on / off state and magnetic force of the electromagnet (272) at different positions are controlled to change the overall shape of the second airbag (260) to adapt to the shape of the well wall. Then, gas is injected into the two auxiliary airbags (261) to stabilize the overall expansion state of the second airbag (260). Then, the vertical movement distance of the second electric telescopic rod (250) is further controlled to squeeze the main airbag (262) and realize the compensation of the squeezing force on the well wall to improve the stability after fixing.

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