Rock core resistivity measuring device and coring drilling tool

Abstract

The invention discloses a core resistivity measuring device and a coring drilling tool, and relates to the technical field of drilling coring, the core resistivity measuring device comprises an outer pipe, a measuring pipe and a measuring assembly, one end of the outer pipe is used for being connected with a drill bit, the other end of the outer pipe is used for being connected with an outer sleeve, and the measuring pipe is rotatably connected in the outer pipe; a first conductive part and a second conductive part are arranged in the measuring tube, are in signal connection with the measuring assembly, and can be in contact with a rock core entering the measuring tube; the measuring assembly can electrify the rock core extending into the measuring tube through the first conductive part and the second conductive part and obtain the resistivity of the rock core. The rock core resistivity measuring device and the coring drilling tool can complete resistivity measurement during coring operation, so that resistivity data can be compared with a real rock core in time and calibrated with the real rock core in time.

Description

Technical Field

[0001] The invention relates to the technical field of drilling and coring, in particular to a core resistivity measuring device and a coring drill. Background Art

[0002] Whether it is oil and gas resource exploration or earth science research, the measurement of formation resistivity is very necessary. At present, the measurement of formation resistivity is mostly completed by logging operations. Conventional resistivity logging mostly measures the resistivity of the well wall after completing the drilling of a section of the well. However, at this time, the well wall has been soaked and eroded by the drilling fluid for a long time, and may even be damaged by the drilling machinery. Relying solely on logging operations is not conducive to formation evaluation and identification. At this time, coring operations are required to obtain the core material, and compare and calibrate the resistivity data measured by the logging operation. The process is relatively complicated. Although more advanced resistivity measurement technology while drilling has emerged, it can only be used during full drilling after coring operations, and it cannot be completed synchronously with coring operations. The resistivity data obtained is separated from the core material data obtained during coring operations in time and space. After the core physical data obtained in the early stage are brought to the surface, the measured resistivity may also change due to changes in temperature, pressure or stress, and there is a possibility of distortion, which is not conducive to timely comparison and calibration of core resistivity data with core physical data. Therefore, there is an urgent need for a core resistivity measurement device and coring drill that can complete the resistivity measurement while coring, use core physical data, and calibrate resistivity logging data and formation identification models more timely, eliminating the steps of electrical logging operations. Summary of the invention

[0003] The purpose of the present invention is to provide a core resistivity measuring device and a coring drill to solve the problems existing in the above-mentioned prior art. The device can complete the resistivity measurement while coring, utilize the core physical data, calibrate the resistivity logging data and the formation identification model more timely, and save the steps of electrical logging operation.

[0004] To achieve the above object, the present invention provides the following solutions:

[0005] The present invention provides a core resistivity measuring device, comprising: an outer tube, a measuring tube and a measuring assembly, wherein one end of the outer tube is used to connect a drill bit, and the other end is used to connect an outer casing, the measuring tube is rotatably connected inside the outer tube, a first conductive part and a second conductive part are provided inside the measuring tube, the first conductive part and the second conductive part are both connected to the measuring assembly signal, the first conductive part and the second conductive part are both able to contact the core entering the measuring tube, and the measuring assembly can energize the core extending into the measuring tube through the first conductive part and the second conductive part and obtain the resistivity of the core.

[0006] In some embodiments, the measuring tube includes an electron tube and a core tube, one end of the electron tube is threadedly connected to one end of the core tube, and the other end of the core tube is used to be connected to the inner suspension of the drilling tool.

[0007] In some embodiments, the measuring tube further includes a retaining spring sleeve and a retaining spring, one end of the retaining spring sleeve is fixedly connected to an end of the electron tube away from the core tube, and the retaining spring is arranged in the retaining spring sleeve. The retaining spring can prevent the movement of the core when the core has a tendency to move in a direction away from the core tube.

[0008] In some embodiments, the electron tube includes a first connecting tube, a first insulating ring, a first electrode ring, an insulating tube, a second electrode ring, a second insulating ring, and a second connecting tube that are connected and communicated in sequence, the first electrode ring forms the first conductive part, and the second electrode ring forms the second conductive part.

[0009] In some embodiments, the outer tube includes a tube body, a first electrode contact ring and a second electrode contact ring, the first electrode contact ring and the second electrode contact ring are both fixedly connected to the tube body, the first electrode contact ring and the second electrode contact ring are both coaxially arranged with the tube body, the first electrode contact ring is in contact with the first electrode ring, the second electrode contact ring is in contact with the second electrode ring, the first electrode contact ring and the second electrode contact ring are both connected to the measurement component signal, and the measuring tube is rotatably connected to the tube body.

[0010] In some embodiments, a mounting cavity is defined in the side wall of the tube body, and the measuring component is fixedly connected in the mounting cavity.

[0011] In some embodiments, the measurement component includes a power supply and an integrated circuit, the power supply is signal-connected to the integrated circuit, and the integrated circuit is signal-connected to the first electrode contact ring and the second electrode contact ring, respectively.

[0012] In some embodiments, the integrated circuit includes a processing module, a storage module and a transmission module, the processing module is signal-connected to the storage module and the transmission module respectively, the processing module can obtain the current passing through the core and the voltage across the core and calculate the resistivity of the core, the storage module can store the resistivity calculated by the processing module, the transmission module is used to connect to an external device by signal, and the transmission module can transmit the resistivity calculated by the processing module to the external device.

[0013] In some embodiments, a first annular fixing groove and a second annular fixing groove are provided on the inner wall of the tube body, the inner wall of the first fixing groove and the inner wall of the second fixing groove are covered with an insulating layer, and the first electrode contact ring and the second electrode contact ring are fixedly connected to the insulating layer in the first fixing groove and the insulating layer in the second fixing groove, respectively.

[0014] The present invention also provides a coring drill tool, comprising a drill bit, an outer sleeve, an inner suspension and the above-mentioned core resistivity measuring device, wherein one end of the outer tube is detachably fixedly connected to the drill bit, and the other end is detachably fixedly connected to the outer sleeve, the inner suspension is rotatably connected inside the outer sleeve, and the inner suspension is detachably fixedly connected to one end of the measuring tube.

[0015] Compared with the prior art, the present invention has achieved the following technical effects:

[0016] The core resistivity measuring device provided by the present invention, during the coring operation, after the core enters the measuring tube, it contacts the first conductive part and the second conductive part, and the measuring component can energize the core through the first conductive part and the second conductive part. After that, the measuring component can calculate the resistivity of the core according to the current passing through the core and the voltage at both ends of the core and Ohm's law, thereby completing the measurement of the core resistivity while the coring operation is being performed, avoiding the core resistivity data and the acquired core physical data being separated in time and space, so that the core physical data and the resistivity data can be compared and calibrated in time. Among them, when calculating the core resistivity, the influence of the resistance of other components except the core's own resistance can be ignored, and the output voltage of the measuring component can be directly equivalent to the voltage at both ends of the core, and a voltage detection device can also be connected in parallel to the core to detect the voltage at both ends of the core. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 A cross-sectional view of a core resistivity measuring device in some embodiments of the present invention;

[0019] Figure 2 A cross-sectional view of an electron tube in some embodiments of the present invention;

[0020] Figure 3 A cross-sectional view of an outer tube and a drill bit in some embodiments of the present invention;

[0021] In the figure: 1. outer tube; 11. tube body; 12. first electrode contact ring; 13. second electrode contact ring; 14. mounting cavity; 15. first fixing groove; 16. second fixing groove; 17. insulating layer; 2. measuring tube; 21. electron tube; 211. first connecting tube; 212. first insulating ring; 213. first electrode ring; 214. insulating tube; 215. second electrode ring; 216. second insulating ring; 217. second connecting tube; 22. core tube; 23. retaining spring sleeve; 24. retaining spring; 3. power supply; 4. integrated circuit; 5. core; 6. drill bit. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] The purpose of the present invention is to provide a core resistivity measuring device and a coring drill to solve the problems existing in the above-mentioned prior art. The device can complete the resistivity measurement while coring, utilize the core physical data, calibrate the resistivity logging data and the formation identification model more timely, and save the steps of electrical logging operation.

[0024] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0025] Embodiment 1

[0026] This embodiment provides a core resistivity measurement device, such as Figure 1-3 As shown, it includes: an outer tube 1, a measuring tube 2 and a measuring assembly, one end of the outer tube 1 is used to connect to the drill bit 6, and the other end is used to connect to the outer casing, the measuring tube 2 is rotatably connected in the outer tube 1, and the measuring tube 2 has a first conductive part and a second conductive part, the first conductive part and the second conductive part are both connected to the signal of the measuring assembly, the first conductive part and the second conductive part can both contact the core 5 entering the measuring tube 2, and the measuring assembly can energize the core 5 extending into the measuring tube 2 through the first conductive part and the second conductive part and obtain the resistivity of the core 5.

[0027] In the core resistivity measuring device provided in the present embodiment, during the coring operation, the power system drives the outer casing to rotate, and the outer casing drives the outer casing to rotate and drives the drill bit to rotate and perform the coring operation; after the core 5 enters the measuring tube 2, it contacts the first conductive part and the second conductive part, and the measuring component can energize the core 5 through the first conductive part and the second conductive part. After that, the measuring component can calculate the resistivity of the core 5 according to the current passing through the core 5 and the voltage at both ends of the core 5 and Ohm's law, thereby completing the measurement of the resistivity of the core 5 while performing the coring operation, avoiding the separation of the resistivity data of the core 5 and the physical data of the core 5 in time and space, and also enabling the resistivity data of the core 5 to be compared with the physical data of the core in a timely manner, calibrating the resistivity and formation identification model, and eliminating the step of electrical logging operation. When calculating the resistivity of the core 5, the influence of the resistance of other components except the resistance of the core 5 itself can be ignored, and the output voltage of the measuring component can be directly equivalent to the voltage across the core 5. A voltage detection device can also be connected in parallel to the core 5 to detect the voltage across the core 5.

[0028] In one implementation of this embodiment, the measuring tube 2 includes an electron tube 21 and a core tube 22. One end of the electron tube 21 is threadedly connected to one end of the core tube 22, and the other end of the core tube 22 is used to be connected to the inner suspension of the drilling tool. The core tube 22 and the electron tube 21 are threadedly connected, and the connection reliability is strong. At the same time, the electron tube 21 or the core tube 22 can be disassembled when maintenance is required.

[0029] In one implementation of this embodiment, the measuring tube 2 further includes a circlip sleeve 23 and a circlip 24. One end of the circlip sleeve 23 is fixedly connected to one end of the electron tube 21 away from the core tube 22. The circlip 24 is arranged in the circlip sleeve 23. After the core 5 enters the electron tube 21, the circlip 24 can prevent the core 5 from moving when the core 5 has a tendency to move away from the core tube 22. The core 5 stops extending into the measuring tube 2 after a certain depth. At this time, the core has a tendency to move away from the core tube 22 due to gravity. The circlip 24 can tighten and clamp the core 5, and then the core 5 can be taken out from the well by lifting the drill.

[0030] In one implementation of the present embodiment, the electron tube 21 includes a first connecting tube 211, a first insulating ring 212, a first electrode ring 213, an insulating tube 214, a second electrode ring 215, a second insulating ring 216 and a second connecting tube 217 which are connected and communicated in sequence. The first electrode ring 213 forms a first conductive portion, and the second electrode ring 215 forms a second conductive portion. The first electrode ring 213 and the second electrode ring 215 are both annular, and can have a larger contact area with the core 5 in the circumferential direction, avoiding poor contact caused by too small a contact area. In addition, in order to improve the strength, the first connecting tube 211, the second connecting tube 217 and the outer tube 1 are mostly made of metal. In order to avoid a short circuit between the first electrode ring 213 and the second electrode ring 215, the first insulating ring 212, the insulating tube 214 and the second insulating ring 216 are used to separate the first electrode ring 213 and the second electrode ring 215 separately.

[0031] It should be noted that if the first connecting tube 211 and the second connecting tube 217 are made of insulating materials, the first insulating ring 212 and the second insulating ring 216 may not be provided.

[0032] To facilitate the connection between the first electrode ring 213 and the second electrode ring 215 and the measuring component, in one implementation of the present embodiment, the outer tube 1 includes a tube body 11, a first electrode contact ring 12 and a second electrode contact ring 13, the first electrode contact ring 12 and the second electrode contact ring 13 are both fixedly connected in the tube body 11, the first electrode contact ring 12 and the second electrode contact ring 13 are both coaxially arranged with the tube body 11, the first electrode contact ring 12 contacts with the first electrode ring 213, the second electrode contact ring 13 contacts with the second electrode ring 215, the first electrode contact ring 12 and the second electrode contact ring 13 are both connected to the measuring component signal, and the measuring tube is rotatably connected in the tube body 11.

[0033] In one implementation of this embodiment, a mounting cavity 14 is provided in the side wall of the tube body 11, and the measuring assembly is fixedly connected in the mounting cavity 14. By arranging the measuring assembly in the mounting cavity 14, the measuring assembly is protected by the tube wall of the outer tube 1 to prevent the measuring assembly from colliding with the outside and being damaged.

[0034] In one implementation of this embodiment, the measuring component includes a power supply 3 and an integrated circuit 4, the power supply 3 is signal-connected to the integrated circuit 4, and the integrated circuit 4 is signal-connected to the first electrode contact ring 12 and the second electrode contact ring 13. The power supply 3 can supply power to the integrated circuit 4, and the integrated circuit 4 can introduce current into the first electrode contact ring 12 and the second electrode contact ring 13. The integrated circuit 4 can also calculate the resistivity of the core 5 according to the current passing through the core 5 and the voltage at both ends of the core 5.

[0035] In one implementation of this embodiment, the integrated circuit 4 includes a processing module, a storage module and a transmission module connection relationship. The processing module is respectively connected to the storage module and the transmission module by signal. The processing module can obtain the current passing through the core 5 and the voltage at both ends of the core 5 and calculate the resistivity of the core 5. The storage module can store the resistivity calculated by the processing module. The transmission module is used to connect with the external device signal. The transmission module can transmit the resistivity calculated by the processing module to the external device. The resistivity of the core 5 can be obtained through the processing module, the storage module can store the resistivity value so that the staff can call it at any time, and the transmission module can be connected to an external device, such as a computer of the staff, and transmit data so that the staff can obtain data at any time.

[0036] In one implementation of the present embodiment, a first annular fixing groove 15 and a second annular fixing groove 16 are provided on the inner side wall of the tube body 11, and the inner side wall of the first fixing groove 15 and the inner side wall of the second fixing groove 16 are both covered with an insulating layer 17, and the first electrode contact ring 12 and the second electrode contact ring 13 are respectively fixedly connected to the insulating layer 17 in the first fixing groove 15 and the insulating layer 17 in the second fixing groove 16. In order to ensure the strength of the tube body 11, the tube body 11 is mostly made of metal, and the insulating layer 17 can prevent the first electrode contact ring 12 and the second electrode contact ring 13 from being connected to the tube body 11 and causing a short circuit.

[0037] It should be noted that when the tube body 11 is made of insulating material, the insulating layer 17 may not be provided.

[0038] Embodiment 2

[0039] The present embodiment provides a coring drill tool, including a drill bit 6, an outer sleeve, an inner suspension and the core resistivity measuring device of the first embodiment. One end of the outer tube 1 is detachably fixedly connected to the drill bit 6, and the other end is detachably fixedly connected to one end of the outer sleeve. The other end of the outer sleeve is used to connect the drill pipe. The inner suspension is rotatably connected in the outer sleeve, and the inner suspension is detachably fixedly connected to one end of the measuring tube 2.

[0040] The coring drill provided in this embodiment avoids the separation of the core resistivity data and the core physical data obtained in time and space by using the core resistivity measuring device in the first embodiment, so that the obtained core physical can be used to calibrate the resistivity data and the formation identification model in time, eliminating the step of electrical logging operation. Among them, the output end of the power system is connected to the drill rod, and the drill rod can rotate under the drive of the power system to drive the outer casing, the outer tube 1 and the drill bit 6 to rotate, so as to realize the coring operation.

[0041] The steps of measuring using the coring drill in the second embodiment of the present invention are as follows:

[0042] Before drilling, a measurement trigger switch is set on the surface. The measurement trigger switch is connected to the measurement component. The receiving end of the measurement trigger switch is located in the measurement tube.

[0043] During drilling, after the core 5 enters the designated position of the measuring tube 2, the measurement trigger switch is triggered, and the core resistivity is measured using the measuring device; then the drill is pulled out and the core is brought back to the surface, completing the coring and core resistivity measurement operations at the same time.

[0044] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core ideas of the present invention. At the same time, for those skilled in the art, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A core resistivity measuring device, characterized in that: include: An outer tube, a measuring tube and a measuring assembly, wherein one end of the outer tube is used to connect to a drill bit, and the other end is used to connect to an outer casing, the measuring tube is rotatably connected inside the outer tube, the measuring tube has a first conductive part and a second conductive part, the first conductive part and the second conductive part are both connected to the measuring assembly signal, the first conductive part and the second conductive part can both contact with a core entering the measuring tube, and the measuring assembly can energize the core extending into the measuring tube through the first conductive part and the second conductive part and obtain the resistivity of the core.

2. The core resistivity measuring device according to claim 1, characterized in that: The measuring tube comprises an electron tube and a core tube, one end of the electron tube is threadedly connected to one end of the core tube, and the other end of the core tube is used for connecting to the inner suspension of the drilling tool.

3. The core resistivity measuring device according to claim 2, characterized in that: The measuring tube also includes a retaining spring sleeve and a retaining spring, one end of the retaining spring sleeve is fixedly connected to an end of the electron tube away from the core tube, the retaining spring is arranged in the retaining spring sleeve, and the retaining spring can prevent the movement of the core when the core has a tendency to move in a direction away from the core tube.

4. The core resistivity measuring device according to claim 2, characterized in that: The electron tube includes a first connecting tube, a first insulating ring, a first electrode ring, an insulating tube, a second electrode ring, a second insulating ring and a second connecting tube which are connected and communicated in sequence. The first electrode ring forms the first conductive part, and the second electrode ring forms the second conductive part.

5. The core resistivity measuring device according to claim 4, characterized in that: The outer tube includes a tube body, a first electrode contact ring and a second electrode contact ring, the first electrode contact ring and the second electrode contact ring are both fixedly connected to the tube body, the first electrode contact ring and the second electrode contact ring are both coaxially arranged with the tube body, the first electrode contact ring contacts with the first electrode ring, the second electrode contact ring contacts with the second electrode ring, the first electrode contact ring and the second electrode contact ring are both connected to the measurement component signal, and the measuring tube is rotatably connected to the tube body.

6. The core resistivity measuring device according to claim 5, characterized in that: The side wall of the tube body is provided with an installation cavity, and the measuring component is fixedly connected in the installation cavity.

7. The core resistivity measuring device according to claim 6, characterized in that: The measuring component includes a power supply and an integrated circuit, wherein the power supply is signal-connected to the integrated circuit, and the integrated circuit is signal-connected to the first electrode contact ring and the second electrode contact ring respectively.

8. The core resistivity measuring device according to claim 7, characterized in that: The integrated circuit includes a processing module, a storage module and a transmission module. The processing module is signal-connected to the storage module and the transmission module respectively. The processing module can obtain the current passing through the core and the voltage at both ends of the core and calculate the resistivity of the core. The storage module can store the resistivity calculated by the processing module. The transmission module is used for signal connection with an external device, and the transmission module can transmit the resistivity calculated by the processing module to the external device.

9. The core resistivity measuring device according to claim 5, characterized in that: A first annular fixing groove and a second annular fixing groove are provided on the inner side wall of the tube body, and the inner side wall of the first fixing groove and the inner side wall of the second fixing groove are both covered with an insulating layer, and the first electrode contact ring and the second electrode contact ring are respectively fixedly connected to the insulating layer in the first fixing groove and the insulating layer in the second fixing groove.

10. A coring drill, characterized in that: The invention comprises a drill bit, an outer sleeve, an inner suspension and a core resistivity measuring device as described in any one of claims 1 to 9, wherein one end of the outer tube is detachably fixedly connected to the drill bit, and the other end is detachably fixedly connected to the outer sleeve, the inner suspension is rotatably connected inside the outer sleeve, and the inner suspension is detachably fixedly connected to one end of the measuring tube.

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