A new mechanical structure of a tool for measuring lithology density

Abstract

The application discloses a novel mechanical structure of a through-drill tool lithology density logging instrument probe, and belongs to the technical field of through-drill tool logging. The probe core group can better realize the fixation and shock absorption of long and short gamma detectors and the adjustability of source distance; the probe short tail vertebra on the upper probe shell group is relatively smooth in transition by adopting a small-gradient long-distance arc structure, and when the density probe is pushed out during instrument logging, if the instrument needs to be lowered, the probe can be smoothly slipped to avoid the probe from being stuck, thereby protecting the logging safety of the density probe; the source packaging group adopts a 5700 type source new structure, realizes the generalization and unification of radioactive sources and system instruments, and enables the instrument to be more conveniently and economically used in blocks with 5700 type sources. In addition, the probe can provide three different locking devices according to well conditions and construction processes. In a word, the novel mechanical structure of the through-drill tool lithology density logging instrument probe can be more safely and effectively used in deeper and more complex well conditions.

Description

Technical Field

[0001] This invention belongs to the field of over-drill logging technology and relates to a novel mechanical structure of the probe for an over-drill lithology density logging tool. Background Technology

[0002] The lithology density logging tool uses gamma spectroscopy to distinguish between Compton scattering and the photoelectric effect. A gamma source emits gamma rays into the formation. Two detectors with different source spacings (long and short) measure the intensity and energy of the gamma rays after attenuation in the formation. The medium-energy gamma rays emitted from the source primarily produce the Compton effect, used to measure rock density; the gamma rays that attenuate in the formation produce the photoelectric effect, which can be used to measure the rock properties of the formation. The electron density and photoelectric absorption index of the formation are calculated to determine the bulk density and lithology of the formation. The two detectors with different source spacings are used to reduce the influence of wellbore diameter and wellbore cake on the measurement results. The wellbore diameter is also measured simultaneously for wellbore calibration.

[0003] In recent years, with unconventional and tight oil and gas reservoirs becoming new growth points for oil and gas, the exploration and development of shale gas and tight oil and gas has continued to deepen. Horizontal wells have become the main development method for unconventional oil and gas. Long horizontal wells, deep wells, and inside-casing drilling are increasing year by year. The complexity and non-standardization of drilling rigs and their associated drilling tools, as well as the miniaturization of their water holes, have led to the inability of traditional logging (small diameter) instruments and tools to meet the needs of improving quality and efficiency. There is an urgent need for ultra-small diameter logging instruments that can pass through the drill string. In highly deviated wells, complex wells, and horizontal wells, the application of "logging through the drill string, logging through the drill bit, and external storage logging technology to replace wet joint horizontal well tools" reduces well occupation time and actively supports drilling speed. The logging time for a single well is only one-third of that of conventional drill string transfer logging, and the risk of using radioactive sources is significantly reduced.

[0004] With the increasing depth of oil and gas wells in recent years, higher requirements have been placed on the temperature and pressure indicators of instruments. Instruments that are limited to 150℃ and 103MPa for lithological density can no longer meet the needs of deep well exploration in the field. Summary of the Invention

[0005] The purpose of this invention is to solve the problem that the existing probe mechanical structure cannot meet the requirements of deep well condition detection, and to provide a new type of probe mechanical structure for a drilling tool lithology density logging tool.

[0006] To achieve the above objectives, the present invention employs the following technical solution:

[0007] This invention proposes a novel mechanical structure for a drill string lithology density logging tool probe, comprising a probe electronic core and a probe core assembly. The probe core assembly is mounted on the probe electronic core, and a probe housing assembly is mounted on the outside of the probe core assembly. The probe electronic core and the probe housing assembly are connected via a probe outer tube short connector.

[0008] The probe core assembly includes a short detector, a detector connecting cylinder, and a long detector, which are sequentially installed inside the probe housing assembly. A detector housing is provided outside the short detector, the detector connecting cylinder, and the long detector, and a disc spring is provided at one end of the detector housing.

[0009] Preferably, a first detector adjustment pad and a second detector adjustment pad are provided at the other end of the detector housing.

[0010] Preferably, the probe electronic core includes a short probe electronic tube, a probe frame, a high-voltage preamplifier board, and a multi-core pressure-bearing connector. The high-voltage preamplifier board is installed at the I-shaped position of the probe I-shaped frame, the multi-core pressure-bearing connector is installed at the end of the probe I-shaped frame, and the short probe electronic tube is installed outside the probe frame, the high-voltage preamplifier board, and the multi-core pressure-bearing connector.

[0011] Preferably, both the probe's electronic short outer tube and the probe's outer shell assembly are connected to the probe's outer tube short connector. A probe wear-resistant block is provided on the probe's outer tube short connector, and the probe wear-resistant block is located on the side of the probe that is attached to the well wall.

[0012] Preferably, the probe housing assembly includes a probe housing, on which a long source distance window, a short source distance window, and a source distance window cover with a card are provided; and a short probe tail cone is provided at one end of the probe housing.

[0013] Preferably, the short source distance window is a sealed, 45° angled plug shape.

[0014] Preferably, the long-distance window is made of TC18 material, while the short-distance window and the window cover with card are both made of PEEK material.

[0015] Preferably, an active encapsulation assembly is mounted on the probe housing assembly;

[0016] The source packaging assembly includes a source compartment containing a 5700 type source. The source compartment is fixed to the probe housing by source compartment screws. A source cover is provided outside the source compartment. One end of the source cover is fixed to the source compartment by a cylindrical head screw. A first fixing block and a second fixing block are fixed to the probe housing by a first elastic cylindrical pin. A fixing block sleeve is provided in the first fixing block. The other end of the source cover is fixed to the fixing block sleeve by a source compartment screw with a hole. The source cover rotates and is fixed to the second fixing block through the source cover pin and the second elastic cylindrical pin. The source cover opens and closes with the source cover pin as the axis.

[0017] Preferably, the fixing block sleeve is made of 0cr17Ni4Cu4Nb, and the source cap, source chamber and fixing block are all made of 95WNiFe.

[0018] Preferably, the probe housing assembly is made of tungsten-nickel-iron alloy.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] This invention proposes a novel mechanical structure for a through-drill lithology density logging tool probe. The probe core assembly better achieves the fixation and vibration reduction of both long and short gamma detectors, as well as the adjustability of the source distance. The long and short detectors are dual-channel gamma detectors, one for long-channel and one for short-channel. Each gamma detector consists of a sodium iodide crystal and a photomultiplier tube. The sodium iodide crystal must be used in conjunction with the photomultiplier tube, which is an electronic device that can perform both photoelectric conversion and photoelectron amplification, typically achieving a magnification of up to 10. 8 This allows for the conversion of gamma rays into visible light. When gamma rays enter the sodium iodide crystal, the crystal converts some or all of the ray energy into visible light. This extremely weak scintillation light is coupled through one end face of the crystal and enters the photocathode of the photomultiplier tube. The photocathode of the photomultiplier tube is extremely sensitive to light; even a single photon, if it has sufficient energy, will excite photoelectrons upon hitting the photocathode. After being amplified by the photomultiplier tube, the output electrical pulse signal can be processed using ordinary electronic circuitry. The probe housing assembly secures the probe core assembly, shields the long and short detectors, directs the emission and reception of gamma rays, and connects to external pusher components. The combination of the probe electronic core, probe core assembly, and probe housing assembly enables temperature and pressure parameters to reach 140 MPa and 175°C, making it suitable for deeper well conditions and solving the problems existing in current technologies.

[0021] Furthermore, the probe housing is entirely made of tungsten-nickel-iron alloy, unlike the stainless steel housing with shielding blocks used in similar instruments. This provides better shielding against gamma rays coming directly from the radiation source, resulting in purer gamma rays received by the detector after attenuation by the strata, and stronger anti-interference capabilities. Simultaneously, the instrument's mechanical assembly is simplified. The short-source-pitch window is a sealed, 45° angled polymer plug.

[0022] Furthermore, the short tail cone of the probe on the probe housing assembly adopts a relatively smooth transition with a small slope and a long arc structure. This unique design detail ensures that when the instrument's logging density probe is extended, if the instrument needs to be lowered, the probe can smoothly slide off to avoid getting stuck, thus protecting the logging safety of the density probe.

[0023] Furthermore, a wear-resistant block is installed on the probe. The size of the wear-resistant block is slightly larger than the outer diameter of the probe shell. When the instrument rubs against the well wall, the wear-resistant block will play a role in friction first, which can extend the wear life of the probe shell.

[0024] Furthermore, the 5700 source is used, achieving standardization and universality for the instrument series, and making it more convenient and economical for field use. Currently, no other drilling tool lithology density logging probe is known to use this source packaging structure. Attached Figure Description

[0025] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a mechanical structure diagram of the probe of the novel over-drilling lithology density logging tool of the present invention.

[0027] Figure 2 This is a structural diagram of the probe electronic core of the present invention.

[0028] Figure 3 This is a structural diagram of the probe core assembly of the present invention.

[0029] Figure 4 The diagram shows the structure of the probe housing assembly of the present invention ((a) is the front view of the probe housing assembly, and (b) is the top view of the probe housing assembly).

[0030] Figure 5 The diagram shows the connection structure of the probe's electronic short outer tube in this invention ((a) is a connection diagram of the probe's electronic short outer tube and the probe housing assembly, (b) is a structural diagram of the connecting sleeve, and (c) is a structural diagram of the cylindrical head screw).

[0031] Figure 6 This is a structural diagram of the source packaging group of the present invention.

[0032] Figure 7 This is a structural diagram of the semi-locking device of the probe of the present invention.

[0033] Figure 8 This is a structural diagram of the full-locking device of the probe of the present invention.

[0034] The components include: 21. Probe electronic core; 22. Probe core assembly; 23. Probe housing assembly; 24. Source packaging assembly; 31. Probe electronic short outer tube; 32. Probe frame; 33. High-voltage preamplifier board; 34. Multi-core pressure-bearing connector; 41. Disc spring; 42. Long detector; 43. Detector housing; 44. Detector connecting cylinder; 45. Short detector; 46. First detector adjustment pad; 47. Second detector adjustment pad; 51. Probe housing; 52. Long source distance window; 53. Short source distance window; 54. Source window cover with clip; 55. Probe short tail cone; 56. Probe connecting pin; 57. Cylindrical pin; 61. Connecting sleeve; 62. Probe wear-resistant block; 63. Cylindrical head screw; 64. Probe outer tube short connector; 71. 5700 type source, 710 fixing block sleeve, 711 first fixing block, 712 source cover pin, 713 second elastic cylindrical pin, 72 source screw, 73 second fixing block, 74 first elastic cylindrical pin, 75 source pressure cap, 76 cylindrical head screw, 77 source chamber, 78 source chamber screw, 79 source chamber screw with hole, 81 probe pull screw, 82 pull probe spring, 83 first O-ring, 84 probe pull rod, 85 probe insert screw, 86 second O-ring, 87 probe tail cone insert. Detailed Implementation

[0035] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0036] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0037] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0038] In the description of the embodiments of the present invention, it should be noted that if terms such as "upper," "lower," "horizontal," or "inner" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of the invention is in use, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention. Furthermore, terms such as "first" and "second" are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0039] Furthermore, the use of the term "horizontal" does not imply that the component must be absolutely horizontal, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0040] In the description of the embodiments of the present invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in the present invention according to the specific circumstances.

[0041] The present invention will now be described in further detail with reference to the accompanying drawings:

[0042] This invention proposes a novel mechanical structure for the probe of a drilling tool lithology density logging instrument, such as... Figures 1 to 6 As shown, it includes a probe electronic instrument core 21 and a probe core assembly 22. The probe core assembly 22 is mounted on the probe electronic instrument core 21, and a probe housing assembly 23 is mounted on the outside of the probe core assembly 22. The probe electronic instrument core 21 and the probe housing assembly 23 are connected by a probe outer tube short connector 64. The probe housing assembly 23 is made of tungsten-nickel-iron alloy.

[0043] The probe electronic core 21 includes a probe electronic short outer tube 31, a probe frame 32, a high-pressure front-amplifier plate 33, and a multi-core pressure-bearing connector 34. The high-pressure front-amplifier plate 33 is installed on one side of the probe I-shaped frame 32, i.e., the I-shaped position. The multi-core pressure-bearing connector 34 is installed on the other side of the probe I-shaped frame 32, i.e., the end. The probe electronic short outer tube 31 is installed outside the probe frame 32, the high-pressure front-amplifier plate 33, and the multi-core pressure-bearing connector 34. The probe electronic short outer tube 31 and the probe housing assembly 23 are both connected to the probe outer tube short connector 64. A probe wear-resistant block 62 is provided on the probe outer tube short connector 64, and the probe wear-resistant block 62 is located on the side of the probe that is in contact with the well wall.

[0044] The probe core assembly 22 includes a short detector 45, a detector connecting cylinder 44, and a long detector 42, which are sequentially installed inside the probe housing assembly 23. A detector housing 43 is provided outside the short detector 45, the detector connecting cylinder 44, and the long detector 42. A disc spring 41 is provided at one end of the detector housing 43, and a first detector adjustment pad 46 and a second detector adjustment pad 47 are provided at the other end.

[0045] like Figure 4 (a) is a front view of the probe housing assembly, and (b) is a top view of the probe housing assembly. The probe housing assembly 23 includes a probe housing 51, on which a long-distance window 52, ​​a short-distance window 53, and a source window cover with a card are provided; a short probe tail cone 55 is provided at one end of the probe housing 51. Among them, the short-distance window 53 is a sealed plug-shaped piece at a 45° angle. The long-distance window 52 is made of TC18, and the short-distance window 53 and the source window cover with a card are both made of PEEK.

[0046] A source encapsulation assembly 24 is mounted on the probe housing assembly 23. The source encapsulation assembly 24 includes a source chamber 77, inside which is a 5700 type source 71. The 5700 type source 71 is tightened and fixed to the source chamber 77 by source screws 72. The source chamber 77 is fixed to the probe housing 51 by source chamber screws 78. A source pressure cap 75 is provided outside the source chamber 77. One end of the source pressure cap 75 is fixed to the source chamber 77 by a cylindrical head screw 76. A first fixing block 711 and a second fixing block 73 are fixed on the probe housing 51 by a first elastic cylindrical pin 74. A fixing block sleeve 710 is provided in the first fixing block 711. The other end of the source pressure cap 75 is fixed to the fixing block sleeve 710 by a source chamber screw with a hole 79. The source pressure cap 75 rotates and is fixed to the second fixing block 73 by a source cap pin 712 and a second elastic cylindrical pin 713. The source pressure cap 75 is opened and closed with the source cap pin 712 as the axis. The fixing block sleeve 710 is made of 0cr17Ni4Cu4Nb, while the source cap 75, source chamber 77, and fixing block 711 are all made of 95WNiFe. The source cap 75 is tightened and fixed to the source chamber 77 by two M4*10 socket head cap screws 76. The first fixing block 711 and the second fixing block 73 are both fixed to the density probe housing 51 by two 5*30 first elastic cylindrical pins 74. The second elastic cylindrical pin 713 is 2*8 in size. Disassembling and assembling the 5700 type source requires removing and installing one source screw 72, one source chamber screw 78, and two perforated source chamber screws 79.

[0047] Specifically, the probe's electronic core 21 is connected to external circuits via a multi-core pressure-bearing connector 34. The high-voltage preamplifier board 33 is fixed to the probe's I-shaped frame 32 by four M3X8 cylindrical head screws. The high-voltage preamplifier board 33, the DHP, is mainly divided into two parts: high-voltage generation from the detector and pre-amplification of the gamma signal from the long and short source distance detectors. It consists of a high-voltage module and a long and short-channel pre-amplification module. The high-voltage module is a voltage-controlled high-voltage output. Under the action of the high-voltage control signal, it outputs a positive high voltage (+HV, range +1000VDC~+1500VDC), which is simultaneously connected to the dynode (multiplier) of the photomultiplier tube of the long and short-channel detector. The pre-amplification circuit amplifies the electronic pulses from the detector's photomultiplier tube to obtain the long and short-channel pulse signals, which are then sent to the next stage for processing. The high-voltage preamplifier board DHP is placed on the probe's I-shaped frame, inside the density instrument probe, close to the detector, which helps improve measurement accuracy.

[0048] The probe core assembly 22 primarily houses the long and short detectors, providing fixation, shielding, vibration damping, and fine-tuning of the source distance. The long detector 42 and short detector 45 are threaded onto both sides of the detector connecting cylinder 44. Both the detector connecting cylinder 44 and the detector housing 43 are made of tungsten-nickel-iron, providing shielding. The first detector adjustment pad 46 is 0.5mm thick, and the second detector adjustment pad 47 is 1mm thick. The number of the first and second detector adjustment pads 46 and 47 can be increased or decreased according to the scale effect to achieve adjustable source distance. The disc spring 41 finally presses the entire probe core assembly together, providing fixation and vibration damping. The long and short detectors are dual-channel gamma detectors (long and short channels). The gamma detector consists of a sodium iodide crystal and a photomultiplier tube, forming a separate system containing voltage divider resistors, load resistors, coupling capacitors, etc. Sodium iodide crystals are used in conjunction with photomultiplier tubes, which are electronic devices that can perform both photoelectric conversion and photoelectron amplification, typically achieving a magnification of 10^6. 8 This means that when gamma rays enter the sodium iodide crystal, the crystal converts some or all of the ray energy into visible light (or scintillation light). This extremely weak scintillation light is coupled through one end face of the crystal and enters the photocathode of the photomultiplier tube. The photocathode of the photomultiplier tube is extremely sensitive to light; even a single photon, if it has enough energy, will excite a photoelectron upon hitting the photocathode. After being amplified by the photomultiplier tube, the output electrical pulse signal can be processed using ordinary electronic circuits.

[0049] The probe housing assembly 23 fits against the well wall, securing the probe core assembly 22, shielding the long and short detectors, directional emission and reception of gamma rays, and connecting to external pusher components. The probe housing assembly 23 is entirely made of tungsten-nickel-iron alloy, unlike the stainless steel housing with shielding blocks used in similar instruments. This provides better shielding against gamma rays directly from the radiation source, resulting in purer gamma rays received by the detector after attenuation by the formation, and stronger anti-interference capabilities. It also simplifies the instrument's mechanical assembly. The long-source window 52 is made of titanium alloy and is fixed to the probe housing 51 by a tungsten-nickel-iron long-source window pressure plate. The long-source window 52 is made of TC18, while the short-source window 53 and the source-clamping window cover 54 are both made of PEEK. The short-source window 53 is a sealed, 45° angled polymer plug. The probe short tail cone 55 on the probe housing assembly 23 is secured to the probe by two probe connecting pins 56 and a 4x20 cylindrical pin 57. The use of a gentle, long-distance circular arc structure ensures a smooth transition. This unique design detail prevents the density probe from getting stuck when the instrument is lowered, thus protecting the logging safety of the density probe.

[0050] like Figure 5 As shown, (a) is a connection diagram of the probe's electronic short outer tube and the probe housing assembly, (b) is a structural diagram of the connecting sleeve, and (c) is a structural diagram of the cylindrical head screw. The probe's electronic short outer tube 31 and the probe housing 51 are connected to the probe's outer tube short connector 64 via four connecting sleeves 61 and four M4X8 cylindrical head screws 63, thus integrating the probe's electronic short outer tube 31 and the probe housing 51 into a single unit. A probe wear-resistant block 62 is located on the side of the probe that is in contact with the well wall, and its size is slightly larger than the outer diameter of the probe housing. When the instrument rubs against the well wall, the wear-resistant block acts as the first point of contact, extending the wear life of the probe housing 51.

[0051] The source encapsulation group 24 mainly realizes the fixing and disassembly of the source. The new through-drill lithology density logging tool probe adopts the 5700 source 71, realizing the standardization and universality of the instrument series, and making it more convenient and economical for field use. Currently, no other through-drill lithology density logging tool probe is known to use this source encapsulation structure.

[0052] When the instrument is run downhole, the new type of through-drill-tool lithology density logging tool has three locking mechanisms between the probe and the density pusher body. One is a semi-locking device, meaning the probe can be extended halfway. Another is a full-locking device, meaning the probe cannot be extended. A third is without any accessories, meaning the probe can be fully extended. The appropriate probe mechanism is selected on-site based on the well conditions and drilling techniques. For example... Figure 7 The diagram shows the probe's semi-locking device, which allows the probe to be extended halfway. It includes a probe pull screw 81, a probe pull spring 82, a first O-ring AS568-010 83, and a probe pull rod 84. Figure 8The image shows a fully locking device for the probe, meaning the probe cannot be extended. This includes the probe insert screw 85, the second O-ring AS568-012 86, and the probe tail cone insert 87. Another type retains the aperture, without any accessories, allowing the probe to be fully extended. The appropriate probe mechanism should be selected on-site based on the well conditions and construction process.

[0053] This invention proposes a novel mechanical structure for a lithology density logging tool probe, achieving temperature and pressure performance of 140 MPa and 175°C, suitable for deeper well conditions. The probe core assembly 22 better secures and dampes the long and short gamma detectors, and offers adjustable source spacing. The wear-resistant block 62 design extends the service life of the probe housing 51. The integrated tungsten-nickel-iron probe housing 51 better shields against direct gamma rays from the radioactive source, providing better anti-interference. The probe's short tail cone 55 on the probe housing assembly 23 features a smooth transition with a small slope and long arc structure, preventing the probe from getting stuck during instrument lowering and ensuring safe logging operation. The source encapsulation assembly 24 uses a new structure based on the 5700-type source 71, achieving universality and standardization between the radioactive source and the EILog system instrument, making the instrument more convenient and economical to use in areas with the 5700-type source 71. Furthermore, the probe can provide three different locking devices depending on the well condition and construction process. In summary, the mechanical structure of this new type of over-drill lithology density logging tool probe can be used more safely and with better measurement results in deeper and more complex well conditions.

[0054] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. 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 novel mechanical structure for a probe of a drilling tool lithology density logging instrument, characterized in that, It includes a probe electronic instrument core (21) and a probe core assembly (22), the probe core assembly (22) is mounted on the probe electronic instrument core (21), and a probe housing assembly (23) is mounted on the outside of the probe core assembly (22); the probe electronic instrument core (21) and the probe housing assembly (23) are connected by a probe outer tube short connector (64); The probe core assembly (22) includes a short detector (45), a detector connecting cylinder (44) and a long detector (42) installed sequentially in the probe housing assembly (23); a detector housing (43) is provided outside the short detector (45), the detector connecting cylinder (44) and the long detector (42), and a disc spring (41) is provided at one end of the detector housing (43). The probe housing assembly (23) includes a probe housing (51), on which a long source distance window (52), a short source distance window (53), and a source distance window cover with a card are provided; a short probe tail cone (55) is provided at one end of the probe housing (51). An active package assembly (24) is mounted on the probe housing assembly (23); The source packaging assembly (24) includes a source compartment (77), inside which is a 5700 type source (71). The source compartment (77) is fixed to the probe housing (51) by source compartment screws (78). A source pressure cap (75) is provided outside the source compartment (77). One end of the source pressure cap (75) is fixed to the source compartment (77) by a cylindrical head screw (76). A first fixing block (711) is fixed to the probe housing (51) by a first elastic cylindrical pin (74). The first fixed block (711) is provided with a fixed block sleeve (710), and the other end of the source cover (75) is fixed to the fixed block sleeve (710) by a source chamber screw (79) with holes; the source cover (75) is rotated and fixed with the second fixed block (73) by the source cover pin (712) and the second elastic cylindrical pin (713); the source cover (75) is opened and closed with the source cover pin (712) as the axis.

2. The novel through-drill lithology density logging tool probe mechanical structure according to claim 1, characterized in that, A first detector adjustment pad (46) and a second detector adjustment pad (47) are provided at the other end of the detector housing (43).

3. The novel through-drill lithology density logging tool probe mechanical structure according to claim 1, characterized in that, The probe electronic core (21) includes a probe electronic short outer tube (31), a probe frame (32), a high voltage preamplifier board (33), and a multi-core pressure-bearing connector (34). The high voltage preamplifier board (33) is installed at the I-shaped position of the probe I-shaped frame (32). The multi-core pressure-bearing connector (34) is installed at the end of the probe I-shaped frame (32). The probe electronic short outer tube (31) is installed outside the probe frame (32), the high voltage preamplifier board (33), and the multi-core pressure-bearing connector (34).

4. The novel through-drill lithology density logging tool probe mechanical structure according to claim 3, characterized in that, The probe electronic short outer tube (31) and the probe outer shell assembly (23) are both connected to the probe outer tube short connector (64). The probe outer tube short connector (64) is provided with a probe wear-resistant block (62), which is located on the side of the probe that is attached to the well wall.

5. The novel through-drill lithology density logging tool probe mechanical structure according to claim 1, characterized in that, The short source distance window (53) is a sealed 45° angled plug shape.

6. The novel through-drill lithology density logging tool probe mechanical structure according to claim 1, characterized in that, The long-distance window (52) is made of TC18, while the short-distance window (53) and the window cover with card (54) are both made of PEEK.

7. The novel through-drill lithology density logging tool probe mechanical structure according to claim 1, characterized in that, The fixing block sleeve (710) is made of 0cr17Ni4Cu4Nb, and the source pressure cap (75), source chamber (77) and fixing block (711) are all made of 95WNiFe.

8. The novel through-drill lithology density logging tool probe mechanical structure according to claim 1, characterized in that, The probe housing assembly (23) is made of tungsten-nickel-iron alloy.

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