A downhole borehole-based encapsulated gamma detector

Abstract

The application discloses a packaged gamma detector based on downhole drilling, and relates to the technical field of gamma detectors, which comprises a shell, an accommodating cavity is formed in the shell, a scintillator is arranged in the accommodating cavity and used for detecting gamma rays, and a photomultiplier is fixedly connected to one side of the accommodating cavity away from the scintillator and used for receiving optical signals. When the detector is subjected to axial impact, the shell and the photomultiplier generate axial displacement, the vibration ring triggers the air buffer due to inertia, the impact energy is absorbed through air viscous damping, under axial or radial impact, the movement of the slip ring drives synchronous radial movement of all radial resistance blocks, the shell inner wall is actively pressed or loosened, dynamic deviation correction of the supporting sleeve and the scintillator is realized, the optical path is aligned, drilling precision is improved, and the quality of drilling a well hole for underwater oil and gas extraction equipment is directly improved.

Description

Technical Field

[0001] This invention relates to the field of gamma detector technology, and in particular to a packaged gamma detector based on downhole drilling. Background Technology

[0002] Subsea oil and gas production equipment, mainly referring to subsea production systems, is a complex combination of equipment placed on the seabed for the extraction and collection of oil and gas. Compared to traditional offshore platforms, this type of subsea oil and gas production equipment is better adapted to deep water and harsh sea conditions, and is a key technology for developing deep-water and marginal oil and gas fields.

[0003] To ensure that subsea oil and gas production equipment accurately reaches high-quality reservoirs, accurate formation information must be obtained in real time during drilling to guide the drilling trajectory. Measurement while drilling (MWD) and logging while drilling (LWD) technologies have emerged as core means of achieving geological steering. Among them, natural gamma ray detection, as a fundamental method for identifying lithology, directly determines the accuracy of geological assessments based on the performance of its downhole measurement equipment.

[0004] However, in practical applications, some unresolved issues remain. The following are some common problems with encapsulated gamma detectors used in downhole drilling: Drill bit rock breaking generates severe and random vibrations and impacts, easily leading to physical damage to the detector, loose connections, and a surge in signal noise. These faults severely interfere with real-time measurements, directly affecting the guidance accuracy and efficiency of drilling operations, thus impacting the well completion quality and final recovery benefits of subsequent subsea oil and gas production equipment. Summary of the Invention

[0005] The purpose of this section is to outline some aspects of embodiments of the present invention and to briefly describe some preferred embodiments. Simplifications or omissions may be made in this section, as well as in the abstract and title of this application, to avoid obscuring the purpose of these documents; however, such simplifications or omissions should not be construed as limiting the scope of the invention.

[0006] In view of the problems existing in the above and / or existing encapsulated gamma detectors based on downhole drilling, the present invention is proposed.

[0007] Therefore, the problem to be solved by this invention is how to solve the damage caused by vibration and impact during the measurement while drilling of gamma detectors, and to greatly improve the stability of gamma detectors, thereby improving the operating efficiency of subsea oil and gas production equipment.

[0008] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a packaged gamma detector based on downhole drilling, comprising: a housing having an internal cavity; a scintillator disposed within the cavity for detecting gamma rays; a photomultiplier tube fixedly connected within the cavity to the side away from the scintillator for receiving optical signals; and a buffer assembly disposed on the scintillator for isolating axial and radial vibrations. The buffer assembly includes a support sleeve connected to the scintillator, a vibration ring disposed between the support sleeve and the photomultiplier tube, and two sides of the vibration ring connected to the photomultiplier tube and the support sleeve respectively via air buffers. An adjustment groove is provided on the side of the support sleeve away from the air buffer, the sidewall of the adjustment groove communicating with the air buffer via an air passage. A slip ring for adjusting the buffer stroke of the air buffer is slidably connected within the adjustment groove, and a radial support is connected to the side of the slip ring away from the air buffer.

[0009] As a preferred embodiment of the encapsulated gamma detector based on downhole drilling according to the present invention, the air buffer includes an outer cylinder embedded in the support sleeve, an inner cylinder fixedly connected inside the outer cylinder, a piston slidably connected inside the inner cylinder, and the side of the piston near the vibration ring being fixedly connected to the vibration ring via a connecting rod.

[0010] As a preferred embodiment of the encapsulated gamma detector based on downhole drilling described in this invention, the outer diameter of the inner cylinder is smaller than the inner diameter of the outer cylinder, and grooves are provided at both ends of the inner cylinder, so that an air passage for airflow is formed between the inner cylinder and the outer cylinder.

[0011] As a preferred embodiment of the encapsulated gamma detector based on downhole drilling according to the present invention, the radial support includes a radial abutment and an inclined pressure block. The outer wall of the support sleeve is provided with a plurality of mounting grooves spaced apart on the circumferential side. The opening position of the mounting groove is slidably connected to the radial abutment that contacts the housing. The bottom of the radial abutment is provided with an inclined surface on the side near the slip ring and is slidably connected to the inclined pressure block. The side of the inclined pressure block away from the radial abutment is fixedly connected to the slip ring.

[0012] As a preferred embodiment of the encapsulated gamma detector based on downhole drilling according to the present invention, wherein: an air nozzle is connected to the side of the outer cylinder near the vibration ring, and a sealing sleeve is connected to the outer wall of the air nozzle.

[0013] As a preferred embodiment of the encapsulated gamma detector based on downhole drilling according to the present invention, the support sleeve has a circular groove in the middle, a sleeve is slidably connected in the circular groove, and the sleeve is fixedly connected to the scintillator.

[0014] As a preferred embodiment of the encapsulated gamma detector based on downhole drilling according to the present invention, a support groove is provided on the side of the circular groove away from the vibration ring, one side of the sleeve extends into the support groove and is fixedly connected to the support ring, and a spring that contacts the housing is fixedly connected to the side wall of the support ring.

[0015] As a preferred embodiment of the encapsulated gamma detector based on downhole drilling according to the present invention, wherein: a light guide sleeve is fixedly connected to the side of the scintillator near the photomultiplier tube, and the diameter of the light guide sleeve gradually increases on the side near the photomultiplier tube to form a flared portion.

[0016] As a preferred embodiment of the encapsulated gamma detector based on downhole drilling according to the present invention, wherein: a light-collecting cover is fixedly connected to the side of the photomultiplier tube near the scintillator, and the diameter of the light-collecting cover gradually decreases on the side near the scintillator to form a conical part for covering the flared part.

[0017] As a preferred embodiment of the encapsulated gamma detector based on downhole drilling described in this invention, wherein: a toothed ring is fixedly connected to the inner wall of the vibration ring, a sun gear is connected to the toothed ring through a planetary carrier, the planetary carrier is rotatably connected to the vibration ring, the sun gear is fixedly connected to the sleeve, and a clearance groove for avoiding the light guide sleeve is provided in the middle of the sun gear.

[0018] The beneficial effects of this invention are as follows: By setting up a buffer component, when the detector is subjected to axial impact, the housing and photomultiplier tube generate axial displacement. Due to inertia, the vibration ring triggers the air buffer component, which absorbs the impact energy through air viscosity damping. Under axial or radial impact, the movement of the slip ring will drive all radial blocks to move synchronously radially, actively pressing or relaxing the inner wall of the housing, realizing the dynamic correction of the support sleeve and scintillator, ensuring the optical path alignment, and improving drilling accuracy. This directly improves the quality of drilling wells for underwater oil and gas production equipment. Attached Figure Description

[0019] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of a packaged gamma detector based on downhole drilling.

[0021] Figure 2 This is a diagram of the internal structure of a packaged gamma detector based on downhole drilling.

[0022] Figure 3This is a schematic diagram of the buffer component in a packaged gamma detector based on downhole drilling.

[0023] Figure 4 This is a schematic diagram of the support sleeve in a packaged gamma detector based on downhole drilling.

[0024] Figure 5 This is a schematic diagram of the air buffer component in a packaged gamma detector based on downhole drilling.

[0025] Figure 6 This is a schematic diagram of the vibration ring structure in a packaged gamma detector based on downhole drilling.

[0026] Figure 7 This is a schematic diagram of the light guide sleeve and light receiver in a packaged gamma detector based on downhole drilling.

[0027] In the diagram: 1. Shell; 2. Scintillator; 3. Photomultiplier tube; 4. Buffer assembly; 41. Support sleeve; 42. Vibration ring; 43. Air buffer; 431. Outer cylinder; 432. Inner cylinder; 433. Piston; 434. Connecting rod; 44. Slip ring; 45. Radial support; 451. Radial abutment; 452. Inclined pressure block; 5. Receiving cavity; 6. Adjustment groove; 7. Air passage one; 8. Groove; 9. Air passage two; 10. Mounting groove; 11. Inclined surface; 12. Air nozzle; 13. Sealing sleeve; 14. Circular groove; 15. Sleeve; 16. Support groove; 17. Support ring; 18. Spring; 19. Light guide sleeve; 20. Flared part; 21. Light collecting cover; 22. Conical part; 23. Gear ring; 24. Planetary carrier; 25. Sun gear; 26. Clearance groove. Detailed Implementation

[0028] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0029] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0030] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that is mutually exclusive with other embodiments.

[0031] Example 1, referring to Figures 1 to 7This is the first embodiment of the present invention, which provides a packaged gamma detector based on downhole drilling. The packaged gamma detector includes a housing 1, a scintillator 2, a photomultiplier tube 3, and a buffer assembly 4. It is installed inside the drill collar of a subsea oil and gas production equipment for measurement while drilling. The scintillator 2 detects gamma rays, and the photomultiplier tube 3 converts fluorescence into electrical pulse signals and transmits them to the surface, providing guidance for drilling operations in the subsea oil and gas production equipment. The buffer assembly 4 absorbs impact and protects the internal components.

[0032] The scintillator 2, photomultiplier tube 3, and buffer assembly 4 are encapsulated in the housing 1. Therefore, the housing 1, which is the only part in contact with the outside world, needs to further improve its surface corrosion resistance compared to the internal components. For example, electroless nickel plating, especially high-phosphorus electroless nickel plating, can provide a uniform, dense, and high-hardness amorphous coating with excellent corrosion resistance and wear resistance. Moreover, the coating thickness is controllable, which improves the service life of the gamma detector.

[0033] Specifically, the housing 1 has an internal cavity 5, which contains a scintillator 2 for converting gamma rays into visible light and a photomultiplier tube 3 for receiving and amplifying the light signal emitted by the scintillator 2. This constitutes the core detection unit of the gamma detector, which can be used for gamma measurement while drilling inside the oil drill collar.

[0034] The buffer assembly 4 is disposed on the scintillator 2 and is used to isolate axial and radial vibrations. The buffer assembly 4 includes a support sleeve 41 connected to the scintillator 2. A vibration ring 42 is disposed between the support sleeve 41 and the photomultiplier tube 3. The two sides of the vibration ring 42 are respectively connected to the photomultiplier tube 3 and the support sleeve 41 through air buffers 43.

[0035] When the detector is subjected to a severe axial impact transmitted from the drill collar, the housing 1 and the photomultiplier tube 3 fixed thereon will undergo axial displacement, while the vibrating ring 42 tends to remain stationary due to inertia, thereby compressing the air buffer 43 on one side. The compressed air flows slowly to the other side through the internal flow channel, converting the impact kinetic energy into heat energy dissipation in the process, providing crucial axial buffering for the entire detection core, and effectively protecting the brittle scintillator 2 and the delicate photomultiplier tube 3 from damage caused by instantaneous overload impact.

[0036] An adjustment groove 6 is provided on the side of the support sleeve 41 away from the air buffer 43. The side wall of the adjustment groove 6 is connected to the air buffer 43 through the air passage 7. A slip ring 44 for adjusting the buffer stroke of the air buffer 43 is slidably connected in the adjustment groove 6. A radial support member 45 is connected on the side of the slip ring 44 away from the air buffer 43.

[0037] When the detector is subjected to radial impact or eccentricity, the position of the slip ring 44 will change. On the one hand, this will finely adjust the air pressure in the air buffer 43 through the air passage 7, affecting its buffering characteristics; on the other hand, the slip ring 44 will drive the radial support 45 to move, making it press against or loosen against the inner wall of the housing 1, thereby dynamically correcting the radial deviation and providing auxiliary support for the support sleeve 41 and the scintillator 2, ensuring that the luminous surface of the scintillator 2 always maintains good parallel alignment with the photocathode window of the photomultiplier tube 3, and ensuring that the underwater oil and gas production equipment obtains stable measurement data.

[0038] Since the support sleeve 41 integrates an air buffer 43, a slip ring 44, and a radial support 45, in order to ensure the installation of the air buffer 43, slip ring 44, and radial support 45, the support sleeve 41 is composed of an air buffer 43 mounting sleeve and a radial support 45 mounting sleeve, which are connected by threads. The adjustment groove 6 for accommodating the slip ring 44 is opened on the side of the radial support 45 mounting sleeve close to the air buffer 43 mounting sleeve. This allows the air passage 7 to be directly connected to the adjustment groove 6, and also allows the slip ring 44 to drive the radial support 45 to move when it slides.

[0039] The scintillator 2 and photomultiplier tube 3 mentioned above are both existing technologies, and the working principle of this part is also existing technology, which can be clearly understood by those skilled in the art, and will not be described in detail here.

[0040] Example 2, refer to Figures 3-5 This is the second embodiment of the present invention, which is based on the previous embodiment.

[0041] Specifically, the air buffer 43 includes an outer cylinder 431 embedded in the support sleeve 41, an inner cylinder 432 fixedly connected inside the outer cylinder 431, a piston 433 slidably connected inside the inner cylinder 432, and the side of the piston 433 near the vibration ring 42 is fixedly connected to the vibration ring 42 via a connecting rod 434.

[0042] The outer diameter of the inner cylinder 432 is smaller than the inner diameter of the outer cylinder 431. Both ends of the inner cylinder 432 are provided with grooves 8, so that an air passage 2 9 is formed between the inner cylinder 432 and the outer cylinder 431 for air flow. The piston 433 slides in the inner cylinder 432. The spaces on both sides of the piston are connected to each other through the grooves 8 at both ends of the inner cylinder 432 and the air passage 2 9 formed by the gap between the inner and outer cylinders, thus forming a complete "air spring-damper" system.

[0043] When the vibrating ring 42 drives the piston 433 to move, the air on one side is compressed and the other side is stretched to form a negative pressure. The compressed air flows slowly to the low-pressure side through the groove 8 and the second air passage 9, generating a smooth damping force, thereby efficiently absorbing impact energy and improving the reliability of downhole tools in underwater oil and gas production equipment.

[0044] An air nozzle 12 is connected to the side of the outer cylinder 431 near the vibrating ring 42. A sealing sleeve 13 is connected to the outer wall of the air nozzle 12 by threads. The sealing sleeve 13 is made of high-temperature resistant polyether ether ketone, which allows the sealing sleeve 13 to maintain a stable connection with the air nozzle 12 in a high-temperature environment, thereby ensuring the airtightness of the air buffer 43.

[0045] After the air buffer component 43 is installed, air is injected into the outer cylinder 431 through the air nozzle 12, creating positive pressure air inside the air buffer component 43 to pressurize the piston 433, so that both sides of the piston 433 are under pressure. Since the side of the piston 433 away from the connecting rod 434 has a larger contact area with the air, the piston 433 will be pushed back to its original position by the air under the pressure difference, ensuring the long-term stability of the gamma detector and ensuring the long-term stability of the detector in the operation of underwater oil and gas production equipment.

[0046] Among them, since the air buffer 43 is mainly buffered by the damping pressure generated when the piston 433 slides and the sudden increase in air pressure, the positive pressure can be controlled in the range of 1.2-1.5 atmospheres, which can be used to ensure that the piston 433 is pushed back to its original position by the pressure difference on both sides after the buffering is completed.

[0047] The radial support 45 includes a radial abutment 451 and an inclined pressure block 452. The outer wall of the support sleeve 41 is provided with a plurality of mounting grooves 10 spaced apart on the circumferential side. The opening of the mounting groove 10 is slidably connected to the radial abutment 451 which is in contact with the housing 1. The bottom of the radial abutment 451 is provided with an inclined surface 11 on the side near the slip ring 44 and is slidably connected to the inclined pressure block 452. The side of the inclined pressure block 452 away from the radial abutment 451 is fixedly connected to the slip ring 44.

[0048] When the slip ring 44 moves axially due to changes in air pressure or under force, it will push the inclined pressure block 452 to move synchronously. The inclined pressure block 452 slides along the inclined surface 11, converting the axial movement of the slip ring 44 into the radial movement of the radial abutment block 451. The multiple radial abutments 451 arranged circumferentially can extend or retract simultaneously, like an adjustable chuck, thereby achieving dynamic centering and radial support for the support sleeve 41 and the scintillator 2, effectively resisting the sway caused by radial impact, and ensuring the accuracy of underwater oil and gas production equipment in complex formations.

[0049] The unique shock absorption design greatly extends the service life of traditional gamma detectors, increasing their lifespan by more than two times.

[0050] Example 3, referring to Figure 3 and Figure 4 This is the third embodiment of the present invention, which is based on the first two embodiments.

[0051] Specifically, a circular groove 14 is provided in the middle of the support sleeve 41, and a sleeve 15 is slidably connected in the circular groove 14. The sleeve 15 is fixedly connected to the scintillator 2. The sleeve 15 can slide axially within a certain range in the circular groove 14 of the support sleeve 41, so that the scintillator 2 is floatingly installed in the support sleeve 41.

[0052] A support groove 16 is provided on the side of the circular groove 14 away from the vibration ring 42. One side of the sleeve 15 extends into the support groove 16 and is fixedly connected to the support ring 17. A spring 18 that contacts the housing 1 is fixedly connected to the side wall of the support ring 17, providing a flexible base support for the scintillator 2.

[0053] The preload of spring 18 stabilizes the scintillator 2 in the absence of impact. When subjected to axial disturbance, spring 18 allows it to undergo a small displacement and self-reset. This two-stage flexible design, working in conjunction with air buffer 43 and radial support 45, constitutes a multi-level shock protection system, significantly improving the stability of the scintillator 2 in the drilling vibration environment of underwater oil and gas production equipment.

[0054] Example 4, refer to Figure 6 and Figure 7 This is the fourth embodiment of the present invention, which is based on the first three embodiments.

[0055] Specifically, a light guide sleeve 19 is fixedly connected to the side of the scintillator 2 near the photomultiplier tube 3. The diameter of the light guide sleeve 19 gradually increases on the side near the photomultiplier tube 3 to form a flared part 20.

[0056] A light-collecting cover 21 is fixedly connected to the side of the photomultiplier tube 3 near the scintillator 2. The diameter of the light-collecting cover 21 gradually decreases on the side near the scintillator 2 to form a conical part 22 for covering the flared part 20.

[0057] In terms of optical path design, the nested structure of the flared part 20 and the conical part 22 forms a highly efficient optical funnel. Even if there is a slight axial or radial relative displacement between the scintillator 2 and the photomultiplier tube 3, the scintillator light can be collected to the maximum extent and introduced into the photomultiplier tube 3, ensuring the signal transmission stability of the underwater oil and gas production equipment.

[0058] A toothed ring 23 is fixedly connected to the inner wall of the vibrating ring 42. A sun gear 25 is connected to the inside of the toothed ring 23 through a planetary carrier 24. The planetary carrier 24 is rotatably connected to the vibrating ring 42. The sun gear 25 is fixedly connected to the sleeve 15. A clearance groove 26 for avoiding the light guide sleeve 19 is opened in the middle of the sun gear 25.

[0059] When the detector housing 1 rotates at high speed with the drill collar of the subsea oil and gas production equipment, the vibration ring 42 and its gear ring 23 are driven to attempt to follow the rotation through the coupling of the air buffer 43. However, since the sun gear 25, which is fixed to the sleeve 15 (and scintillator 2), is initially at rest or low speed, according to the kinematic principle of the planetary gear system, under the constraint of the conservation of angular momentum of the system, the rotation of the gear ring 23 (input end) will cause the planet carrier 24 to rotate, and at the same time, the sun gear 25 (output end) will generate a rotation in the opposite direction to the input end with a significantly reduced speed. The high rotational speed transmitted from the drill collar to the detector is converted into an extremely low reverse rotational speed of the scintillator 2, which greatly eliminates the periodic vibration noise and signal modulation effect caused by high-speed rotation, thereby improving the stability and signal-to-noise ratio of the gamma measurement spectrum and optimizing the operational data quality of the subsea oil and gas production equipment.

[0060] In use, this gamma detector is installed inside the drill collar of the subsea oil and gas production equipment for measurement while drilling.

[0061] When the housing 1 is driven to rotate at high speed by the drill collar, the vibrating ring 42 is driven to rotate through the air buffer 43. The gear ring 23 fixed to it drives the planetary gear set to work. Since the scintillator 2 has a large moment of inertia due to the flexible support, the rotation of the sun gear 25 is hindered, which forces the planet carrier 24 to rotate. Ultimately, the sun gear 25 and the scintillator 2 produce a slow rotation with a significantly reduced speed that is opposite to the rotation direction of the housing 1, thereby effectively suppressing the vibration noise and periodic signal fluctuations caused by high-speed rotation.

[0062] When the detector is subjected to an axial impact, the housing 1 and the photomultiplier tube 3 generate axial displacement. Due to inertia, the vibrating ring 42 lags behind and pushes the piston 433 to compress the air on one side via the connecting rod 434. The compressed air flows slowly to the other side through the groove 8 and the second air passage 9, absorbing the impact energy through air viscosity damping.

[0063] Simultaneously, the change in air pressure pushes the slip ring 44 to move through air passage 7, preventing a sudden increase in pressure within the buffer chamber and allowing the vibrating ring 42 to have a larger buffer stroke, thereby reducing the peak force of the axial impact. After the impact force weakens, the air pressure difference pushes the piston 433 and the vibrating ring 42 to reset.

[0064] When subjected to radial impact, the radial blocks 451 of the support sleeve 41 are compressed, pushing the slip ring 44 to move via the inclined surface 11, changing the volume of the adjusting groove 6, and then affecting the pressure in the air buffer 43 through the air passage 7, thus using air buffering to weaken the impact. More importantly, under axial or radial impact, the movement of the slip ring 44 will drive all the radial blocks 451 to move radially synchronously, actively pressing or releasing the inner wall of the housing 1, realizing dynamic correction of the support sleeve 41 and the scintillator 2, and ensuring optical path alignment.

[0065] The funnel-shaped optical path design of the light guide sleeve 19 and the light collecting cover 21, combined with multi-level flexible support and buffer, ensures that the photons generated by the scintillator 2 can be efficiently and stably collected into the photomultiplier tube 3 under various impacts and vibrations, and finally output a high-fidelity gamma spectrum signal for the underwater oil and gas production equipment, directly serving the drilling guidance and operation efficiency improvement.

[0066] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A packaged gamma detector based on downhole drilling, characterized in that: include, The shell (1) has an internal cavity (5); A scintillator (2) is disposed in a receiving cavity (5) for detecting gamma rays; A photomultiplier tube (3) is fixedly connected in the cavity (5) on the side away from the scintillator (2) to receive light signals; A buffer assembly (4) is provided on the scintillator (2) to isolate axial and radial vibrations. The buffer assembly (4) includes a support sleeve (41) connected to the scintillator (2). A vibration ring (42) is provided between the support sleeve (41) and the photomultiplier tube (3). The two sides of the vibration ring (42) are connected to the photomultiplier tube (3) and the support sleeve (41) respectively through an air buffer (43). An adjustment groove (6) is provided on the side of the support sleeve (41) away from the air buffer (43). The side wall of the adjustment groove (6) is connected to the air buffer (43) through an air passage (7). A slip ring (44) for adjusting the buffer stroke of the air buffer (43) is slidably connected in the adjustment groove (6). A radial support (45) is connected on the side of the slip ring (44) away from the air buffer (43). The radial support (45) includes a radial abutment (451) and an inclined pressure block (452). The outer wall of the support sleeve (41) is provided with a plurality of mounting grooves (10) spaced apart on the circumferential side. The opening of the mounting groove (10) is slidably connected to the radial abutment (451) which is in contact with the housing (1). The bottom of the radial abutment (451) is provided with an inclined surface (11) on the side near the slip ring (44) and is slidably connected to the inclined pressure block (452). The side of the inclined pressure block (452) away from the radial abutment (451) is fixedly connected to the slip ring (44).

2. The encapsulated gamma detector based on downhole drilling as described in claim 1, characterized in that: The air buffer (43) includes an outer cylinder (431) embedded in the support sleeve (41), an inner cylinder (432) fixedly connected inside the outer cylinder (431), and a piston (433) slidably connected inside the inner cylinder (432). The side of the piston (433) near the vibration ring (42) is fixedly connected to the vibration ring (42) via a connecting rod (434).

3. The encapsulated gamma detector based on downhole drilling as described in claim 2, characterized in that: The outer diameter of the inner cylinder (432) is smaller than the inner diameter of the outer cylinder (431). Both ends of the inner cylinder (432) are provided with grooves (8), so that an air passage (9) is formed between the inner cylinder (432) and the outer cylinder (431) for air flow.

4. The encapsulated gamma detector based on downhole drilling as described in claim 3, characterized in that: The outer cylinder (431) is connected to an air nozzle (12) on the side near the vibrating ring (42), and a sealing sleeve (13) is connected to the outer wall of the air nozzle (12).

5. The encapsulated gamma detector based on downhole drilling as described in claim 1, characterized in that: The support sleeve (41) has a circular groove (14) in the middle, and a sleeve (15) is slidably connected in the circular groove (14). The sleeve (15) is fixedly connected to the scintillator (2).

6. The encapsulated gamma detector based on downhole drilling as described in claim 5, characterized in that: A support groove (16) is provided on the side of the circular groove (14) away from the vibration ring (42). One side of the sleeve (15) extends into the support groove (16) and is fixedly connected to a support ring (17). A spring (18) that contacts the housing (1) is fixedly connected to the side wall of the support ring (17).

7. The encapsulated gamma detector based on downhole drilling as described in claim 6, characterized in that: The scintillator (2) is fixedly connected to a light guide sleeve (19) on the side near the photomultiplier tube (3). The diameter of the light guide sleeve (19) gradually increases on the side near the photomultiplier tube (3) to form a flared part (20).

8. The encapsulated gamma detector based on downhole drilling as described in claim 7, characterized in that: The photomultiplier tube (3) is fixedly connected to a light-collecting cover (21) on the side near the scintillator (2). The diameter of the light-collecting cover (21) gradually decreases on the side near the scintillator (2) to form a conical part (22) for covering the flared part (20).

9. The encapsulated gamma detector based on downhole drilling as described in claim 8, characterized in that: A toothed ring (23) is fixedly connected to the inner wall of the vibrating ring (42). A sun gear (25) is connected to the inside of the toothed ring (23) through a planetary carrier (24). The planetary carrier (24) is rotatably connected to the vibrating ring (42). The sun gear (25) is fixedly connected to the sleeve (15). A clearance groove (26) for avoiding the light guide sleeve (19) is opened in the middle of the sun gear (25).

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