Logging instrument and logging method

Abstract

The invention relates to a logging instrument and a logging method, and relates to the technical field of logging equipment. The logging instrument comprises a shell, a heat preservation assembly, a detector assembly and an inner circuit assembly. A first cavity is formed in the shell; the heat preservation assembly is arranged in the first cavity, a second cavity is formed in the heat preservation assembly, and the heat preservation assembly is used for isolating the high temperature of the stratum; the detector assembly is arranged in the second cavity, and the detector assembly is used for receiving gamma rays of the stratum and outputting corresponding electric signals; the inner circuit assembly is electrically connected with the detector assembly, and the inner circuit assembly is used for receiving and processing an electric signal output by the detector assembly; and the inner circuit assembly comprises a power supply module, and the power supply module is arranged in the second cavity. According to the technical scheme, the problem that an existing dual-detector natural gamma-ray spectrum logging instrument cannot meet the requirement for the high-temperature logging environment of a deep well and an ultra-deep well can be solved.

Description

Technical Field

[0001] The present invention relates to the technical field of logging equipment, and particularly to a logging tool and a logging method. Background Art

[0002] Logging is a method of measuring geophysical parameters by using the electrochemical properties, electrical conductivity, acoustic properties, radioactivity and other geophysical properties of rock formations. In oil and gas drilling, logging must be carried out after drilling to the designed well depth to obtain various petroleum geological and engineering technical data.

[0003] In the field of oil and gas logging, natural gamma-ray spectrometry logging is a common logging method, which is a logging method that records natural gamma rays in different energy ranges. Since most of the gamma rays emitted by the formation are generated by the decay of three radioactive isotopes - potassium, thorium, and uranium, natural gamma-ray spectrometry logging can give the contents of potassium, thorium, and uranium in the formation. Thus, it provides data for determining the shale content of the reservoir, analyzing the sedimentary environment and oil generation conditions, and dividing lithology.

[0004] At present, the dual-detector design has been widely applied to natural gamma-ray spectrometry logging tools. However, with the increasing number of deep wells and ultra-deep wells, deep wells and ultra-deep wells are often accompanied by high-temperature logging environments. The existing dual-detector natural gamma-ray spectrometry logging tools usually arrange the power supply module outside the thermos flask, resulting in the power supply module being unable to work normally under the high-temperature conditions of deep wells and ultra-deep wells. Therefore, the dual-detector natural gamma-ray spectrometry logging tool can no longer meet the logging requirements of such deep wells and ultra-deep wells, causing most of these wells to be exempt from logging and the geological evaluation data to be missing. Summary of the Invention

[0005] Embodiments of the present invention provide a logging tool and a logging method to at least solve the problem that the existing dual-detector natural gamma-ray spectrometry logging tool cannot meet the high-temperature logging environment of deep wells and ultra-deep wells.

[0006] In a first aspect, an embodiment of the present invention provides a logging tool, including:

[0007] A housing having a first cavity therein;

[0008] A thermal insulation assembly disposed in the first cavity, the thermal insulation assembly having a second cavity therein, and the thermal insulation assembly being used for isolating the high temperature of the formation;

[0009] A detector assembly disposed in the second cavity, the detector assembly being used for receiving gamma rays of the formation and outputting corresponding electrical signals;

[0010] An internal circuit assembly electrically connected to the detector assembly, the internal circuit assembly being used for receiving and processing the electrical signals output by the detector assembly;

[0011] Among them, the internal circuit component includes a power module, and the power module is arranged in the second cavity.

[0012] In one embodiment, the heat preservation component includes:

[0013] A thermos flask, arranged in the first cavity, the thermos flask has opposite first and second ends, and openings are provided on both the first end and the second end;

[0014] A first heat absorber, arranged in the thermos flask, the first heat absorber is located between the first end and the detector component;

[0015] A heat insulation sleeve, arranged in the thermos flask, one end of the heat insulation sleeve is connected to the first heat absorber, and the other end is flush with the end face of the first end;

[0016] A thermos flask screw sleeve, connected to the end of the heat insulation sleeve away from the first heat absorber;

[0017] A second heat absorber, arranged in the thermos flask, the second heat absorber is located between the second end and the detector component;

[0018] Among them, the first heat absorber, the second heat absorber and the thermos flask together form the second cavity.

[0019] In one embodiment, the logging tool includes an external circuit skeleton located in the first cavity, the external circuit skeleton is connected to the thermos flask screw sleeve, and the external circuit skeleton is used to support the external circuit.

[0020] In one embodiment, the internal circuit component includes:

[0021] A first circuit unit, arranged in the second cavity, one end of the first circuit unit is connected to the first heat absorber, and the other end is connected to the detector component, and the first circuit unit is used to process a part of the electrical signals output by the detector component;

[0022] A second circuit unit, arranged in the second cavity, one end of the second circuit unit is connected to the second heat absorber, and the other end is connected to the detector component, and the second circuit unit is used to process another part of the electrical signals output by the detector component.

[0023] In one embodiment, the first circuit unit includes a first high-voltage module, an analog-to-digital conversion module, a communication module, a telemetry module, a first high-voltage filtering and processing module, a first signal processing module, and a first conductive path, and the first conductive path is used for electrical connection with an external circuit;

[0024] The second circuit unit includes a second high-voltage module, a second module signal processing module, a second high-voltage filtering and processing module, and a second conductive path, and the second conductive path is used for electrically connecting with the external circuit.

[0025] In one embodiment, a first wire hole is provided on the first heat absorber, the first wire hole penetrates the first heat absorber in the length direction of the first heat absorber, and the first wire hole is communicated with the opening on the first end for the first conductive path to pass through.

[0026] A second wire hole is provided on the second heat absorber, the second wire hole penetrates the second heat absorber in the length direction of the second heat absorber, and the second wire hole is communicated with the opening on the second end for the second conductive path to pass through.

[0027] In one embodiment, the detector assembly includes:

[0028] A first sleeve connected to one end of the first circuit unit away from the first heat absorber;

[0029] A second sleeve connected to one end of the second circuit unit away from the second heat absorber;

[0030] A first photomultiplier tube disposed in the first sleeve;

[0031] A second photomultiplier tube disposed in the second sleeve;

[0032] A first detector, one end of the first detector abuts against the first photomultiplier tube;

[0033] A second detector, one end of the second detector abuts against the second photomultiplier tube;

[0034] Wherein, the detector assembly includes a connecting block, and one end of the first detector away from the first photomultiplier tube is connected to one end of the second detector away from the second photomultiplier tube through the connecting block.

[0035] In one embodiment, the detector assembly further includes:

[0036] A first elastic member disposed in the first sleeve, one end of the first elastic member abuts against the inner wall of the first sleeve and the other end abuts against the first photomultiplier tube;

[0037] A second elastic member disposed in the second sleeve, one end of the second elastic member abuts against the inner wall of the second sleeve and the other end abuts against the second photomultiplier tube.

[0038] In one embodiment, the length of the first heat absorber is 600 mm, and the length of the second heat absorber is 360 mm.

[0039] Second, an embodiment of the present invention provides a logging method applied to the logging tool as described above, including:

[0040] Lower the logging tool to a preset depth underground;

[0041] Power the detector assembly through the power supply module;

[0042] Receive gamma rays emitted by the formation through the detector assembly and convert the gamma rays into electrical signals;

[0043] Receive the electrical signals through the internal circuit assembly and transmit them to the ground terminal.

[0044] Compared with the prior art, the advantages of the embodiments of the present invention are that by providing a second cavity through the heat insulation assembly, an installation space is provided for the detection assembly and the power supply module, and the high-temperature environment during the logging process is isolated. Compared with the prior art in which the power supply part is arranged outside the thermos flask, in the present invention, the power supply module is arranged in the second cavity of the heat insulation assembly, which can avoid the influence of high-temperature gas during the logging process on the power supply module, enabling the power supply module to work normally during the logging process of deep wells and ultra-deep wells, providing power for the detector assembly of the logging tool, ensuring that the logging tool can also work reliably and stably for a long time under high-temperature conditions, thus meeting the logging requirements of deep wells and ultra-deep wells, providing data for determining the shale content of the reservoir in deep wells and ultra-deep wells, analyzing the sedimentary environment and oil generation conditions, etc., and solving the problem that the existing logging tool cannot meet the high-temperature logging environment of deep wells and ultra-deep wells. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Hereinafter, the present invention will be described in more detail based on embodiments and with reference to the drawings.

[0046] Figure 1 is a cross-sectional view of a logging tool provided by an embodiment of the present invention;

[0047] Figure 2 is Figure 1 the axonometric view of the logging tool provided by the embodiment in

[0048] Figure 3 is Figure 1 the structural schematic diagram of the detector assembly provided by the embodiment in

[0049] Reference numerals:

[0050] 10. Housing; 11. First protective cap; 12. Second protective cap; 13. Upper joint assembly; 20. Thermal insulation assembly; 21. Thermos flask; 22. First heat absorber; 23. Heat insulation sleeve; 24. Thermos flask screw sleeve; 25. Second heat absorber; 30. Detector assembly; 31. First sleeve; 32. Second sleeve; 33. First photomultiplier tube; 34. Second photomultiplier tube; 35. First detector; 36. Second detector; 37. First elastic member; 38. Second elastic member; 39. Connecting block; 40. Inner circuit assembly; 41. First circuit unit; 42. Second circuit unit; 50. Outer circuit framework; 60. Male plug assembly; 70. Female plug assembly. Detailed implementation manners

[0051] It should be noted that, without conflict, the embodiments in the present application and the features in the embodiments may be combined with each other. The present invention will be described in detail below with reference to the drawings and in combination with the embodiments.

[0052] At present, the dual-detector design has been widely applied to natural gamma ray spectrometers. However, with the increasing number of deep wells and ultra-deep wells, deep wells and ultra-deep wells are often accompanied by high-temperature logging environments. In the existing dual-detector natural gamma ray spectrometers, the power supply module is usually arranged outside the thermos flask to ensure heat dissipation, resulting in the inability of the power supply module to work normally under the high-temperature conditions of deep wells and ultra-deep wells. Therefore, the dual-detector natural gamma ray spectrometers can no longer meet the logging requirements of such deep wells and ultra-deep wells, causing most of these wells to be exempt from logging and the geological evaluation data to be missing.

[0053] As Figure 1 shown, at least one embodiment of the present invention provides a logging tool, including a housing 10, a thermal insulation assembly 20, a detector assembly 30, and an inner circuit assembly 40; a first cavity is provided inside the housing 10; the thermal insulation assembly 20 is arranged inside the first cavity, a second cavity is provided inside the thermal insulation assembly 20, and the thermal insulation assembly 20 is used to isolate the high temperature of the formation; the detector assembly 30 is arranged inside the second cavity, and the detector assembly 30 is used to receive gamma rays from the formation and output corresponding electrical signals; the inner circuit assembly 40 is electrically connected to the detector assembly 30, and the inner circuit assembly 40 is used to receive and process the electrical signals output by the detector assembly 30; wherein, the inner circuit assembly 40 includes a power supply module, and the power supply module is arranged inside the second cavity.

[0054] As can be seen from the above, by providing the second cavity through the heat preservation component 20, an installation space is provided for the detection component and the power module, and the high-temperature environment during the logging process is isolated. Compared with the prior art in which the power supply part is arranged outside the thermos flask 21, in the present invention, the power module is arranged in the second cavity of the heat preservation component 20, which can prevent the power module from being affected by the high-temperature gas during the logging process, enabling the power module to work normally during the logging process of deep wells and ultra-deep wells, providing power for the detector component 30 of the logging tool, ensuring that the logging tool can also work reliably and stably for a long time under high-temperature conditions, thereby meeting the logging requirements of deep wells and ultra-deep wells, providing data for determining the shale content of the reservoir in deep wells and ultra-deep wells, analyzing the sedimentary environment and oil generation conditions, etc., and solving the problem that the existing logging tools cannot meet the high-temperature logging environment of deep wells and ultra-deep wells.

[0055] It should be noted that during assembly, the detector component 30 and the internal circuit component 40 are first connected to each other and then placed in the second cavity of the heat preservation component 20, and then the heat preservation component 20 is placed in the first cavity of the housing 10.

[0056] Preferably, in some embodiments, the maximum pressure-bearing strength of the housing 10 is 206 MPa. As a preference, the housing 10 is made of TC18 titanium alloy material. Compared with traditional stainless steel housings, such as 0Cr17Ni4Cu4Nb and 15-5PH, the TC18 titanium alloy housing has less attenuation of gamma rays of the formation under the premise of ensuring the pressure-bearing and connection strength, which is beneficial to the measurement of the formation gamma energy spectrum. The yield strength and tensile strength of the TC18 titanium alloy material at 260 °C are attenuated compared with those at room temperature. The yield strength (σ 0.2 ) is 900 MPa, and the mechanical pressure-bearing performance calculation is carried out on this basis.

[0057] Preferably, the outer diameter of the housing 10 is 86 mm, the material is TC18, and the yield strength (σ 0.2 ) is calculated as 900 MPa. Taking the design safety factor of 1.08, the inner diameter of the housing 10 is φ61 mm.

[0058] Such as Figure 1 、 Figure 2As shown, in some embodiments, the thermal insulation assembly 20 includes a thermos 21, a first heat absorber 22, a heat insulation sleeve 23, a thermos screw sleeve 24, and a second heat absorber 25; the thermos 21 is disposed in the first cavity, the thermos 21 has opposite first and second ends, and openings are provided on both the first end and the second end; the first heat absorber 22 is disposed in the thermos 21, and the first heat absorber 22 is located between the first end and the detector assembly 30; the heat insulation sleeve 23 is disposed in the thermos 21, one end of the heat insulation sleeve 23 is connected to the first heat absorber 22, and the other end is flush with the end face of the first end; the thermos screw sleeve 24 is connected to the end of the heat insulation sleeve 23 away from the first heat absorber 22; the second heat absorber 25 is disposed in the thermos 21, and the second heat absorber 25 is located between the second end and the detector assembly 30; wherein, the first heat absorber 22, the second heat absorber 25 and the thermos 21 together form a second cavity.

[0059] By providing the first heat absorber 22 and the second heat absorber 25, the high temperature of the formation is effectively isolated, and the heat power consumption of the thermos 21 is reduced by the heat insulation sleeve 23, thereby avoiding the influence of the high temperature during the logging process on the power module and the detector assembly 30 in the thermal insulation cavity. The existing double-detector structure usually uses a single-opening thermos 21, and the circuit wiring occupies the space inside the bottle, resulting in a reduction in the diameter of the detector that can be accommodated in the single-opening thermos 21, causing a decrease in the detection efficiency and detection accuracy. However, in the present invention, openings are provided on both the first end and the second end of the thermos 21, so that the thermos 21 has a double-opening structure, which can cooperate with the first heat absorber 22 and the second heat absorber 25 to complete the circuit wiring, avoiding occupying the space inside the bottle, thereby providing sufficient accommodation space for the detector and ensuring the detection efficiency and detection accuracy of the detector. Therefore, compared with the single-opening thermos 21, when the inner diameters of the double-opening thermos 21 and the single-opening thermos 21 of the present invention are the same, the double-opening thermos 21 of the present invention can accommodate a detector with a larger diameter, and the detection accuracy and detection efficiency are higher.

[0060] Preferably, in some embodiments, the thermos 21 has a cylindrical structure, and there is a reserved gap between the outer wall of the thermos 21 and the inner wall of the housing 10130, and this reserved gap is used for wire routing, and the reserved gap is 2.5 mm - 3 mm. As a preference, the outer diameter of the thermos 21 is 58 mm, and the inner diameter of the thermos 21 is 48 mm.

[0061] Preferably, in some embodiments, the heat insulation sleeve 23 is connected to the thermos screw sleeve 24 and the first heat absorber 22 respectively by screws, the thermos screw sleeve 24 is threadedly connected to the first end of the thermos 21, and the second heat absorber 25 is connected to the thermos 21 by screws.

[0062] As Figure 1 、 Figure 2As shown, in some embodiments, the logging tool includes an outer circuit framework 50 located in the first cavity. The outer circuit framework 50 is connected to the thermos flask spigot 24 and is used to support the external circuit. By providing the outer circuit framework 50, it is convenient for the routing of the external circuit.

[0063] Preferably, in some embodiments, first connectors and second connectors are respectively provided at both ends of the housing 10. The first connector is connected to the first conductive path of the first circuit unit 41, and the second connector is connected to the second conductive path of the second circuit unit 42. Moreover, the first connector and the second connector can be docked with the connectors of other instruments and devices. First protective caps 11 and second protective caps 12 are respectively provided on the first connector and the second connector, and the first protective caps 11 and the second protective caps 12 are used to protect the first connector and the second connector respectively.

[0064] Preferably, in some embodiments, the logging tool further includes an upper connector assembly 13. One end of the upper connector assembly 13 is connected to the outer circuit framework 50, and the other end is connected to the first connector.

[0065] It should be noted that the upper connector assembly 13 is detachably connected to the outer circuit framework 50 and the first connector respectively, so as to facilitate the placement of the heat insulation assembly 20, the detector assembly 30, and the internal circuit assembly 40 into the housing 10 assembly.

[0066] As Figure 1 、 Figure 2 As shown, in some embodiments, the internal circuit assembly 40 includes a first circuit unit 41 and a second circuit unit 42. The first circuit unit 41 is disposed in the second cavity. One end of the first circuit unit 41 is connected to the first heat absorber 22, and the other end is connected to the detector assembly 30. The first circuit unit 41 is used to process a part of the electrical signals output by the detector assembly 30. The second circuit unit 42 is disposed in the second cavity. One end of the second circuit unit 42 is connected to the second heat absorber 25, and the other end is connected to the detector assembly 30. The second circuit unit 42 is used to process another part of the electrical signals output by the detector assembly 30.

[0067] It should be noted that the first circuit unit 41 is electrically connected to the second circuit unit 42.

[0068] Preferably, in some embodiments, the first circuit unit 41 further includes a first circuit board and a first support framework. The first circuit board is mounted on the first support framework, and the first support framework is mounted on the first heat absorber 22 by screws.

[0069] As Figure 2As shown, preferably, in some embodiments, the second circuit unit 42 further includes a second circuit board and a second support frame. The second circuit board is mounted on the second support frame, and the second support frame is mounted on the second heat absorber 25 by screws. A male plug assembly 60 is provided on the second support frame, and a female plug assembly 70 mating with the male plug assembly is provided on the second heat absorber 25. The male plug assembly 60 and the female plug assembly 70 are docked inside the thermos flask 21, thereby completing the electrical connection between the second circuit unit 42 and the second heat absorber 25 and realizing the electrical connection between the second circuit unit 42 and the whole instrument.

[0070] In some embodiments, the first circuit unit 41 includes a first high-voltage module, a digital-to-analog conversion module, a communication module, a telemetry module, a first high-voltage filtering and processing module, a first signal processing module, and a first conductive path for electrically connecting to an external circuit. The second circuit unit 42 includes a second high-voltage module, a second module signal processing module, a second high-voltage filtering and processing module, and a second conductive path for electrically connecting to an external circuit.

[0071] Preferably, in some embodiments, the power supply module is a switching power supply module.

[0072] Since existing logging tools usually use a combination of a power supply module, a transformer, a three-terminal voltage regulator, etc., which have high power and high power consumption. Placing them in the second cavity will increase the total thermal power consumption in the second cavity, and it is necessary to extend the length of the heat absorber to increase the heat absorption capacity to reduce the temperature in the second cavity, but this will increase the length of the logging tool, which is not conducive to the simplified design of the instrument. However, in the present invention, by combining a switching power supply module with a digital-to-analog conversion module and discarding high-power and high-power consumption devices such as transformers and three-terminal voltage regulators, the thermal power consumption is greatly reduced, the heat release is reduced, and the temperature rise in the second cavity is avoided, thereby ensuring that the power supply module can work stably in the second cavity. In addition, there is no need to extend the length of the heat absorber to increase the heat absorption capacity, avoiding increasing the length of the logging tool and ensuring the simplified design of the logging tool.

[0073] It should be noted that the first high-voltage module, the digital-to-analog conversion module, the communication module, the telemetry module, the first high-voltage filtering and processing module, the first signal processing module, and the power supply module are all mounted on the first circuit board.

[0074] It should also be noted that the second high-voltage module, the second module signal processing module, and the second high-voltage filtering and processing module are all mounted on the second circuit board.

[0075] It should also be noted that cables are connected to the first connector and the second connector, and high-voltage alternating current of 180V is transmitted to the first circuit unit 41 through the cables. The high-voltage alternating current of 180V enters the digital-to-analog conversion module, and the digital-to-analog conversion module converts the high-voltage alternating current of 180V into low-voltage direct current of 10V - 20V. After the low-voltage direct current of 10V - 20V enters the power supply module, the power supply module converts the low-voltage direct current of 10V - 20V into the voltages required by each module and supplies power to each module;

[0076] Before the power supply module supplies power to the detector assembly 30, the 10 - 20V low-voltage direct current of the power supply module enters the first high-voltage module and the second high-voltage module respectively. The high-voltage electricity leaving the first high-voltage module and the second high-voltage module enters the first high-voltage filtering and processing module and the second high-voltage filtering and processing module respectively for filtering processing. The high-voltage electricity leaving the first high-voltage filtering and processing module and the second high-voltage filtering and processing module enters the first photomultiplier tube 33 and the second photomultiplier tube 34 respectively, and supplies power to the first photomultiplier tube 33 and the second photomultiplier tube 34. The first detector 35 and the second detector 36 convert the gamma rays of the formation received into optical pulse signals. The optical pulse signal received by the first detector 35 is converted into photoelectrons through the photocathode of the first photomultiplier tube 33, and a negative voltage pulse is output after being amplified by the first photomultiplier tube 33. The optical pulse signal received by the second detector 36 is converted into photoelectrons through the photocathode of the second photomultiplier tube 34, and a negative voltage pulse is output after being amplified by the second photomultiplier tube 34. The electrical signals output by the first photomultiplier tube 33 and the second photomultiplier tube 34 enter the first signal processing module and the second signal processing module respectively, and after amplitude discrimination, frequency division, shaping, and power amplification, they are converted into digital signals through analog-to-digital conversion. The digital signals are sent to the communication module, the communication module sends the digital signals to the telemetry module, and the telemetry module finally sends the measured data to the ground.

[0077] In some embodiments, a first wire hole is provided on the first heat absorber 22. The first wire hole penetrates the first heat absorber 22 in the length direction of the first heat absorber 22, and the first wire hole is communicated with the opening on the first end for the first conductive path to pass through; a second wire hole is provided on the second heat absorber 25. The second wire hole penetrates the second heat absorber 25 in the length direction of the second heat absorber 25, and the second wire hole is communicated with the opening on the second end for the second conductive path to pass through.

[0078] By providing the first wire hole on the first heat absorber 22 and the second wire hole on the second heat absorber 25 to realize the routing of the first conductive path and the second conductive path, there is no need to separately provide space in the second cavity for routing, avoiding occupying the space in the second cavity due to routing, so as to ensure the diameter size of the detection assembly, and thus ensure the detection efficiency and detection accuracy of the detector assembly 30.

[0079] It should be noted that the first conductive path and the second conductive path include, but are not limited to, wires.

[0080] It should also be noted that the length direction of the first heat absorber 22 is parallel to the length direction of the second heat absorber 25.

[0081] As Figure 3 shown, in some embodiments, the detector assembly 30 includes a first sleeve 31, a second sleeve 32, a first photomultiplier tube 33, a second photomultiplier tube 34, a first detector 35, and a second detector 36; the first sleeve 31 is connected to one end of the first circuit unit 41 away from the first heat absorber 22; the second sleeve 32 is connected to one end of the second circuit unit 42 away from the second heat absorber 25; the first photomultiplier tube 33 is disposed in the first sleeve 31; the second photomultiplier tube 34 is disposed in the second sleeve 32; one end of the first detector 35 abuts against the first photomultiplier tube 33; one end of the second detector 36 abuts against the second photomultiplier tube 34; wherein, the detector assembly 30 includes a connection block 39, and one end of the first detector 35 away from the first photomultiplier tube 33 is connected to one end of the second detector 36 away from the second photomultiplier tube 34 through the connection block 39.

[0082] The detector assembly 30 forms a dual-detector design through the first detector 35 and the second detector 36, improving the detection efficiency and accuracy of the detector assembly 30, reducing the statistical fluctuation error, and ensuring the detection ability of the detector assembly 30 for thin layers and thin interbeds. The gamma rays of the formation are converted into optical pulse signals through the first detector 35 and the second detector 36. The optical pulse signal received by the first detector 35 is converted into photoelectrons through the photocathode of the first photomultiplier tube 33, and a negative voltage pulse is output after being amplified by the first photomultiplier tube 33; the optical pulse signal received by the second detector 36 is converted into photoelectrons through the photocathode of the second photomultiplier tube 34, and a negative voltage pulse is output after being amplified by the second photomultiplier tube 34.

[0083] Preferably, in some embodiments, threading holes are provided on both the first sleeve 31 and the second sleeve 32. Space is reserved for the wires through the threading holes, facilitating the electrical connection of the detector assembly 30 and the internal circuit assembly 40 through the threading holes.

[0084] Preferably, in some embodiments, the first detector 35 is threadedly connected to the first sleeve 31, and the second detector 36 is threadedly connected to the second sleeve 32. The disassembly of the first sleeve 31 and the second sleeve 32 is facilitated through the threaded connection.

[0085] Preferably, in some embodiments, the diameters of both the first detector 35 and the second detector 36 are 47 mm, and the lengths of both the first detector 35 and the second detector 36 are 260 mm.

[0086] Preferably, in some embodiments, the first detector 35 is a NaI crystal detector, a GSO crystal detector, or a LaBr 3 crystal detector, and the second detector 36 is a NaI crystal detector, a GSO crystal detector, or a LaBr 3 crystal detector. More preferably, a NaI crystal detector is selected as the first detector 35 and the second detector 36.

[0087] Preferably, in some embodiments, one end of the first detector 35 away from the first photomultiplier tube 33 is connected to the connection block 39 by a screw, and one end of the second detector 36 away from the second photomultiplier tube 34 is connected to the connection block 39 by a screw.

[0088] As Figure 3 shown, in some embodiments, the detector assembly 30 further includes a first elastic member 37 and a second elastic member 38; the first elastic member 37 is disposed in the first sleeve 31, one end of the first elastic member 37 abuts against the inner wall of the first sleeve 31 and the other end abuts against the first photomultiplier tube 33; the second elastic member 38 is disposed in the second sleeve 32, one end of the second elastic member 38 abuts against the inner wall of the second sleeve 32 and the other end abuts against the second photomultiplier tube 34.

[0089] Preferably, in some embodiments, both the first elastic member 37 and the second elastic member 38 are flat-end opposed wave springs; the first elastic member 37 presses against the first photomultiplier tube 33 to correctly couple the first photomultiplier tube 33 with the glass surface of the first detector 3535. The coupling surface of the first photomultiplier tube 33 and the first detector 35 is coated with a coupling agent; the second elastic member 38 presses against the second photomultiplier tube 34 to correctly couple the second photomultiplier tube 34 with the glass surface of the second detector 36. The coupling surface of the second photomultiplier tube 34 and the second detector 36 is coated with a coupling agent.

[0090] In some embodiments, the length of the first heat absorber 22 is 600 mm, and the length of the second heat absorber 25 is 360 mm. In order to enable the logging tool to work reliably and stably for a long time under ultra-high temperature conditions, by limiting the lengths of the first heat absorber 22 and the second heat absorber 25, the heat absorption length is increased, and the total heat capacity in the thermos 21 is improved.

[0091] At least one embodiment of the present invention further provides a logging method, which is applied to the logging tool according to any embodiment of the present invention. The logging method includes:

[0092] Lower the logging tool to a preset depth underground;

[0093] Power the detector assembly through the power supply module;

[0094] Receive gamma rays emitted by the formation through the detector assembly, and convert the gamma rays into electrical signals;

[0095] Receive the electrical signals through the internal circuit assembly and transmit them to the ground terminal.

[0096] The logging method provided by the present invention has all the technical effects brought by the technical solutions of the above embodiments.

[0097] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation of the present invention. In addition, the features defined as "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, unless otherwise specified, the meaning of "a plurality" is two or more. In the description of the present invention, the first feature being "above" or "below" the second feature may include the first and second features being in direct contact, or may include the first and second features not being in direct contact but being in contact through additional features therebetween.

[0098] In the description of the present invention, the first feature being "above", "over" and "on" the second feature includes the first feature being directly above and obliquely above the second feature, or simply indicating that the first feature has a higher horizontal height than the second feature.

[0099] In the description of the present invention, it should be noted that, unless otherwise clearly defined and limited, the terms "mounted", "connected" and "connected to" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected, or indirectly connected through an intermediate medium, and it may be the internal communication of two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0100] In the description of this specification, the description referring to terms such as "one embodiment", "some embodiments", "schematic embodiments", "examples", "specific examples", or "some examples", etc. means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0101] Although the present invention has been described with reference to the preferred embodiments, various improvements can be made to it and components therein can be replaced with equivalents without departing from the scope of the present invention. In particular, as long as there is no structural conflict, the various technical features mentioned in each embodiment can be combined in any way. The present invention is not limited to the specific embodiments disclosed in the text, but includes all technical solutions falling within the scope of the claims.

Claims

1. A well logging tool, characterized in that: include: A housing having a first cavity therein; A heat-insulating component is disposed in the first cavity, wherein a second cavity is provided in the heat-insulating component, and the heat-insulating component is used to isolate the high temperature of the formation; a detector assembly, disposed in the second cavity, and configured to receive gamma rays from the formation and output corresponding electrical signals; An internal circuit component, electrically connected to the detector component, and used for receiving and processing the electrical signal output by the detector component; Wherein, the internal circuit component includes a power module, and the power module is arranged in the second cavity.

2. The logging tool according to claim 1, characterized in that: The thermal insulation component comprises: A thermos bottle is disposed in the first cavity, the thermos bottle has a first end and a second end opposite to each other, and the first end and the second end are both provided with an opening; A first heat absorber is disposed in the thermos bottle, wherein the first heat absorber is located between the first end and the detector assembly; An insulating sleeve is arranged in the thermos bottle, one end of the insulating sleeve is connected to the first heat absorber, and the other end is flush with the end surface of the first end; A thermos bottle screw sleeve connected to an end of the heat insulating sleeve away from the first heat absorbing body; A second heat absorber is disposed in the thermos bottle, and the second heat absorber is located between the second end and the detector assembly; The first heat absorber, the second heat absorber and the thermos bottle together form the second cavity.

3. The logging tool according to claim 2, characterized in that: The logging instrument comprises an external circuit skeleton located in the first cavity, the external circuit skeleton is connected to the thermos bottle screw sleeve, and the external circuit skeleton is used to support an external circuit.

4. The logging tool according to claim 2, characterized in that: The internal circuit components include: a first circuit unit, disposed in the second cavity, wherein one end of the first circuit unit is connected to the first heat absorber, and the other end is connected to the detector assembly, and the first circuit unit is used to process a portion of the electrical signal output by the detector assembly; The second circuit unit is disposed in the second cavity, one end of the second circuit unit is connected to the second heat absorber, and the other end is connected to the detector assembly, and the second circuit unit is used to process another part of the electrical signal output by the detector assembly.

5. The logging tool according to claim 4, characterized in that: The first circuit unit includes a first high-voltage module, a digital-to-analog conversion module, a communication module remote transmission module, a first high-voltage filtering processing module, a first signal processing module and a first conductive path, wherein the first conductive path is used to be electrically connected to an external circuit; The second circuit unit includes a second high-voltage module, a second module signal processing module, a second high-voltage filtering processing module and a second conductive path, and the second conductive path is used for electrically connecting to the external circuit.

6. The logging tool according to claim 5, characterized in that: The first heat absorbing body is provided with a first wiring hole, the first wiring hole passes through the first heat absorbing body in the length direction of the first heat absorbing body, and the first wiring hole is connected with the opening on the first end, so that the first conductive path can pass through; The second heat absorbing body is provided with a second wiring hole, which passes through the second heat absorbing body in the length direction of the second heat absorbing body, and is connected with the opening on the second end so that the second conductive path can pass through.

7. The logging tool according to any one of claims 4 to 6, characterized in that: The detector assembly comprises: A first sleeve connected to an end of the first circuit unit away from the first heat absorber; a second sleeve connected to an end of the second circuit unit away from the second heat absorber; A first photomultiplier tube is disposed in the first sleeve; A second photomultiplier tube is disposed in the second sleeve; A first detector, one end of which is in contact with the first photomultiplier tube; a second detector, wherein one end of the second detector is in contact with the second photomultiplier tube; Wherein, the detector assembly comprises a connection block, and an end of the first detector away from the first photomultiplier tube and an end of the second detector away from the second photomultiplier tube are connected through the connection block.

8. The logging tool according to claim 7, characterized in that: The detector assembly also includes: A first elastic member is disposed in the first sleeve, one end of the first elastic member abuts against the inner wall of the first sleeve and the other end of the first elastic member abuts against the first photomultiplier tube; The second elastic member is disposed in the second sleeve, one end of the second elastic member abuts against the inner wall of the second sleeve and the other end of the second elastic member abuts against the second photomultiplier tube.

9. The logging tool according to any one of claims 2 to 6, characterized in that: The length of the first heat absorber is 600 mm, and the length of the second heat absorber is 360 mm.

10. A well logging method, applied to the well logging tool as claimed in any one of claims 1 to 9, characterized in that: include: Driving the logging instrument into the well to a preset depth; Supplying power to the detector assembly via the power module; receiving gamma rays emitted by the formation through the detector assembly and converting the gamma rays into electrical signals; The electrical signal is received by the internal circuit component and transmitted to a ground terminal.

Images