Rotary sidewall coring tool

Abstract

The present application relates to a kind of rotary sidewall coring tools, including electronic short section, balanced short section, hydraulic control short section, mechanical execution short section and core storage short section, mechanical execution short section includes mechanical section shell, transmission is arranged in mechanical section shell, transmission is connected with drill bit assembly, transmission is used to drive under the drive of driving device with drill bit assembly Drilling formation, break core, retrieve and overturn, and the axis of drill bit assembly is parallel with the axis of coring tool after overturning, and the side opening of mechanical section shell is provided for drill bit assembly to extend out.The transmission of the rotary sidewall coring tool of the present application can drive under the drive of driving device with drill bit assembly Drilling formation, break core, retrieve and overturn, and the axis of drill bit assembly is parallel with the axis of coring tool after overturning, so as to be able to reduce the diameter of coring tool;It also has the advantages of high reliability.

Description

Technical Field

[0001] This invention belongs to the field of oil and gas exploration and development technology, and specifically relates to a rotating wellbore coring instrument. Background Technology

[0002] As the requirements for detailed evaluation of complex geological structures such as deep formations, deep water, high temperature, high pressure, and highly deviated wells continue to increase, coring operations are becoming increasingly difficult, and the requirements for the reliability and stability of instruments are also becoming more stringent. Currently available coring instruments cannot fully meet the requirements for coring operations in high-temperature, high-reliability, and highly deviated wells, and also suffer from high maintenance costs. Summary of the Invention

[0003] In order to solve all or part of the above problems, the present invention aims to provide a rotary wellbore coring instrument. The transmission device of the rotary wellbore coring instrument of the present invention can drive the drill bit assembly to drill into the formation, break the rock core, retrieve and flip under the drive of the drive device, and has the advantage of high reliability.

[0004] According to one aspect of the present invention, a rotating wellbore coring instrument is provided, comprising an electronic sub, a balancing sub, a hydraulic control sub, a mechanical actuation sub, and a core storage sub. The mechanical actuation sub includes a mechanical sub housing, within which a transmission device is disposed. The transmission device is connected to a drill bit assembly. The transmission device is used to drive the drill bit assembly to drill into the formation, break the core, retract, and flip under the drive of a drive device. After flipping, the axis of the drill bit assembly is parallel to the axis of the coring instrument. The mechanical sub housing is provided with a side opening for the drill bit assembly to extend out.

[0005] Furthermore, the transmission device includes two parallel limiting guide rails, both of which are fixedly connected to the outer shell of the mechanical section. Each limiting guide rail has a first groove, and a moving guide rail is connected to the side of each limiting guide rail away from the other limiting guide rail. Each moving guide rail has a second groove. The drill bit assembly is disposed between the two limiting guide rails, and first sliders are fixedly connected to corresponding sides of the drill bit assembly. Each first slider passes through the corresponding first groove and extends into the second groove. Both moving guide rails are connected to the driving device, which drives the two moving guide rails to move up and down, so as to drive the drill bit assembly to move into the formation, break the rock core, retract, and flip through the cooperation of the first groove and the second groove.

[0006] Furthermore, the upper ends of both motion guide rails are connected to the upper fixed pull plate, and the lower ends of both motion guide rails are connected to the lower fixed pull plate. The driving device is connected to the upper fixed pull plate so that the upper fixed pull plate is driven by the driving device to realize the up and down movement of the two motion guide rails.

[0007] Furthermore, each of the limiting guide rails has a mating groove on the side away from the other limiting guide rail, and each mating groove extends vertically to both ends through the corresponding limiting guide rail. Each moving guide rail is fixedly connected to a mating guide rail that mates with the mating groove.

[0008] Furthermore, the first chute includes a horizontal chute whose length direction is parallel to the drilling direction of the drill bit assembly, and the second chute includes a straight chute. The straight chute and the horizontal chute have an acute angle between them. The driving device is used to drive the two motion guide rails to move up and down, so as to drive the drill bit assembly to move into the formation, break the rock core, and retract through the cooperation of the horizontal chute and the straight chute.

[0009] Furthermore, the first slide groove also includes a first arc-shaped groove, which is disposed at the end of the horizontal slide groove away from the side opening and is connected to the horizontal slide groove. The second slide groove also includes a second arc-shaped groove, which is disposed at the end of the straight slide groove away from the side opening and is connected to the straight slide groove. The two sides of the drill bit assembly are also fixedly connected to second sliders. Each of the limiting guide rails is also provided with a second slider mating groove that is connected to the horizontal slide groove. The driving device is used to drive the two motion guide rails to move so that the second slide groove pushes the first slider through the first arc-shaped groove, so that the second slider moves in the second slider mating groove to realize the flipping of the drill bit assembly.

[0010] Furthermore, the first slider is a rhombus-shaped slider, one set of mutually parallel surfaces of the rhombus-shaped slider contacts the two side walls of the horizontal slide groove, and the other set of mutually parallel surfaces of the rhombus-shaped slider contacts the two side walls of the straight slide groove; the drill bit assembly includes a drill bit and a hydraulic motor connected to the drill bit, and both the first slider and the second slider are mounted on the hydraulic motor; the driving device includes a drilling hydraulic cylinder, and the piston rod of the drilling hydraulic cylinder is connected to the motion guide rail.

[0011] Furthermore, the hydraulic control section includes a hydraulic section body, on which an upper push arm and a reverse push arm are provided. The pushing direction of the upper push arm is opposite to that of the reverse push arm. The outer shell of the mechanical section is provided with a lower push arm, on which the pushing direction of the upper push arm is the same as that of the lower push arm. The reverse push arm can be operated independently to detach the coring instrument from the well wall. The upward push arm and the reverse push arm have the same structure; the reverse push arm includes a reverse push hydraulic cylinder composed of a reverse push cylinder body, a first piston rod, and a second piston rod, wherein the first piston rod is slidably and sealed within the reverse push cylinder body, the first piston rod has a through hole, the second piston rod is slidably and sealed within the through hole, and a push head is fixedly connected to one end of the second piston rod extending out of the first piston rod. The reverse push hydraulic cylinder is connected to a hydraulic control unit, which is used to control the extension of the first piston rod and the second piston rod within the reverse push cylinder body, and to control the retraction of the first piston rod and the second piston rod within the reverse push cylinder body.

[0012] Furthermore, the electronic segment includes a thermal insulation outer shell, within which are disposed a plurality of electronic frames. Each electronic frame is used to fix a circuit board, and each electronic frame has heat-absorbing units at both ends. The length of each heat-absorbing unit is determined by the heat generated by the circuit board on the adjacent electronic frame. A heat-insulating sleeve is disposed above the uppermost heat-absorbing unit within the thermal insulation outer shell, and a heat-insulating filler is disposed below the lowermost heat-absorbing unit within the thermal insulation outer shell. An upper connector is connected to the upper end of the thermal insulation outer shell, and an electronic connector is connected to the lower end of the thermal insulation outer shell. The circuit board passes through the heat-insulating filler and the heat-absorbing unit and connects to the electronic connector.

[0013] Furthermore, the balancing short section is disposed between the electronic short section and the hydraulic control short section. The balancing short section includes a balancing short section housing, within which a balancing cylinder is disposed. A moving piston is disposed within the balancing cylinder, dividing the space within the balancing cylinder into a mud chamber and an oil chamber. A piston tension spring, a moving rod, and a moving rod compression spring are disposed within the oil chamber. One end of the piston tension spring is fixed to one end of the cylinder, and the other end of the piston tension spring is connected to one side of the moving piston. One side of the moving piston is also connected to one end of the moving rod compression spring, and the other end of the moving rod compression spring is connected to one end of the moving rod. A displacement sensor for measuring the displacement of the moving piston is disposed at the other end of the moving rod, and a limit structure is disposed on the other end of the moving rod. A locking structure is also connected to one side of the moving piston, and the moving piston drives the moving rod to move through the cooperation of the locking structure and the limit structure.

[0014] Furthermore, the core storage sub includes several core tubes connected by threads. The core storage sub can be seated at the wellhead via a wellhead chuck. The uppermost core tube is connected to the connecting tube above it via a transition joint. The uppermost core tube is threadedly connected to the transition joint. Several locking blocks are fixedly connected to the upper end of the transition joint. The lower end of the connecting tube has a slot that mates with the locking blocks. The transition joint and the connecting tube are connected by locking blocks and slots. A cotter pin connects the connecting tube and the transition joint.

[0015] As can be seen from the above technical solution, the rotating wellbore coring instrument provided by the present invention has the following beneficial effects: The transmission device of the rotating wellbore coring instrument of the present invention can drive the drill bit assembly to drill into the formation, break the rock core, retract and flip under the drive of the drive device, and after flipping, the axis of the drill bit assembly is parallel to the axis of the coring instrument, thereby reducing the diameter of the coring instrument; at the same time, it has the advantage of high reliability. The present invention adds a thrust arm, which can be used independently to detach the coring instrument from the well wall, thereby solving the problem that the coring instrument is stuck to the well wall and cannot be detached from the well wall. The electronic section of the present invention includes a heat-insulating outer shell, and the electronic skeleton is disposed inside the heat-insulating outer shell, thereby realizing overall heat exchange between the heat-insulating outer shell and the outside world. At the same time, according to the different heat generation of the circuit board on the electronic skeleton, heat-absorbing units of different lengths are configured, so that the internal temperature of the thermos bottle is basically uniform, thereby improving the reliability of the electronic circuit. The core storage section of the present invention can be seated at the wellhead via a wellhead chuck, thereby enabling rapid replacement and assembly of the core tube at the wellhead. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of a rotating wellbore coring instrument according to an embodiment of the present invention; Figure 2 This is a cross-sectional view of the electronic subsection according to an embodiment of the present invention; Figure 3 This is a cross-sectional view of the hydraulic control short section thrust arm portion according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the hydraulic control unit according to an embodiment of the present invention; Figure 5 This is a cross-sectional view of the transmission device portion of the mechanical actuation section according to an embodiment of the present invention; Figure 6 This is a cross-sectional view of the balancing short section according to an embodiment of the present invention; The attached diagram is labeled as follows: Electronic section 1, Balance section 2, Hydraulic control section 3, Mechanical actuation section 4, Core storage section 5, Upper connector 11, Insulated outer shell 12, Heat insulation sleeve 13, Heat absorption unit 14, Electronic frame 15, Heat insulation filler 16, Electronic connector 17, Balance section outer shell 21, Balance cylinder 22, Mud chamber 23, Moving piston 24, Piston tension spring 25, Moving rod compression spring 26, Moving rod 27, Displacement sensor 28, Hydraulic section body 31, Upward push arm 32, Reverse push Support arm 33, reverse thrust cylinder 331, first piston rod 332, second piston rod 333, push head 334, mechanical joint housing 41, lower push arm 42, upper fixed pull plate 43, drill bit 44, hydraulic motor 45, limit guide rail 46, first slide groove 461, horizontal slide groove 4611, first arc groove 4612, second slider mating groove 462, motion guide rail 47, second slide groove 471, second arc groove 4711, straight slide groove 4712, mating guide rail 472, lower fixed pull plate 48. Detailed Implementation

[0017] To better understand the purpose, structure, and function of this invention, a rotating wellbore coring instrument of this invention will be described in further detail below with reference to the accompanying drawings.

[0018] like Figure 1 , Figure 5 As shown, this invention illustrates a rotating wellbore coring device according to an embodiment of the present invention, comprising an electronic sub 1, a balancing sub 2, a hydraulic control sub 3, a mechanical actuation sub 4, and a core storage sub 5. The mechanical actuation sub 4 includes a mechanical sub housing 41, within which a transmission device is disposed. The transmission device is connected to the drill bit assembly and is used to drive the drill bit assembly to drill into the formation, break the core, retract, and flip under the drive of the drive device. After flipping, the axis of the drill bit assembly is parallel to the axis of the coring device. The mechanical sub housing 41 is provided with a side opening for the drill bit assembly to extend out.

[0019] Specifically, the electronic sub-section 1, the balancing sub-section 2, the hydraulic control sub-section 3, the mechanical actuation sub-section 4, and the core storage sub-section 5 constitute the downhole system of the coring instrument in this embodiment. The coring instrument also includes a surface system, which consists of a data acquisition computer, a control panel, and a power supply. The surface system is used to control the downhole system of the coring instrument.

[0020] Among them, the electronic sub-section 1 mainly receives instructions from the ground system and controls the hydraulic control sub-section 3, the mechanical execution sub-section 4, and the core storage sub-section 5 according to the instructions of the ground system to complete the core retrieval operation.

[0021] Electronic sub-unit 1 simultaneously sends various status information of the downhole system to the surface system, including formation GR signal (used for depth calibration), cable head voltage, pump pressure signals of various pumps, drilling displacement signal, core length displacement signal, electronic sub-unit temperature, hydraulic sub-unit temperature, etc.

[0022] The balance section 2 achieves pressure balance between the internal hydraulic oil and the external mud through the movement of the internal piston. At the same time, the balance section 2 is equipped with an oil level detection sensor, which can detect changes in the volume of the internal hydraulic oil.

[0023] The hydraulic control section 3 includes a hydraulic system for controlling the movement of the main and auxiliary push arms, a hydraulic system for controlling drilling, drilling retraction, partition insertion, and push-core movements, and a hydraulic system for controlling the rotation of the hydraulic motor.

[0024] The mechanical actuator section 4 enables the instrument to perform functions such as pushing, coring, core breaking, and core retrieval. It mainly consists of actuators for main pushing, drilling, core length measurement, core storage, and core pushing.

[0025] To reiterate, electronic section 1 is used to communicate with the ground control system and to control hydraulic control section 3 and mechanical actuation section 4; hydraulic control section 3 is used to provide power to mechanical actuation section 4, which is used to perform operations such as pushing, core taking, core breaking, and core retrieval; core storage section 5 is used to store the obtained core samples.

[0026] Furthermore, the mechanical actuation section 4 includes a mechanical section housing 41 and a transmission device disposed within the mechanical section housing 41. The transmission device is used to drive the drill bit assembly to extend from the side opening and drill into the formation to complete the coring operation under the drive of the drive device within the hydraulic control section 3. After the coring operation is completed, the drive device and the transmission device drive the drill bit assembly to break off the rock core and retract it into the mechanical section housing 41. Finally, the drive device and the transmission device drive the drill bit assembly to rotate so that the axis of the drill bit assembly is parallel to the axis of the coring instrument, thereby reducing the diameter of the mechanical section housing 41 accordingly.

[0027] In one embodiment, such as Figure 5As shown, the transmission device includes two parallel limiting guide rails 46, both of which are fixedly connected to the mechanical section housing 41. Each limiting guide rail 46 has a first groove 461. A moving guide rail 47 is connected to the side of each limiting guide rail 46 away from the other limiting guide rail 46. Each moving guide rail 47 has a second groove 471. The drill bit assembly is disposed between the two limiting guide rails 46, and a first slider is fixedly connected to each of the corresponding sides of the drill bit assembly. Each first slider passes through the corresponding first groove 461 and extends into the second groove 471. Both moving guide rails 47 are connected to a drive device. The drive device is used to drive the two moving guide rails 47 to move up and down, so as to drive the drill bit assembly to move into the formation, break the rock core, retract, and flip through the cooperation of the first groove 461 and the second groove 471.

[0028] Specifically, the transmission device includes two limiting guide rails 46 and two moving guide rails 47. The two limiting guide rails 46 are arranged in parallel and are fixedly connected to the mechanical section housing 41. Each limiting guide rail 46 is connected to a moving guide rail 47 on the side away from the other limiting guide rail 46. Both moving guide rails 47 are connected to the drive device so that the drive device can drive the two moving guide rails 47 to move up and down relative to the limiting guide rails 46.

[0029] Furthermore, each limiting guide rail 46 is provided with a first sliding groove 461, and each moving guide rail 47 is provided with a second sliding groove 471. The drill bit assembly is fixedly connected to both sides of the corresponding limiting guide rail 46. The two first sliding blocks pass through the corresponding first sliding groove 461 and extend into the second sliding groove 471. Therefore, during the up and down movement of the two moving guide rails 47, the first sliding blocks are pushed by the second sliding groove 471 to slide in the first sliding groove 461, thereby realizing the movement of the drill bit assembly to drill into the formation, break the rock core, retract, and flip.

[0030] In one embodiment, such as Figure 5 As shown, the upper ends of the two motion guide rails 47 are connected to the upper fixed pull plate 43, and the lower ends of the two motion guide rails 47 are connected to the lower fixed pull plate 48. The driving device is connected to the upper fixed pull plate 43 so that the upper fixed pull plate 43 is driven to move through the driving device to realize the up and down movement of the two motion guide rails 47.

[0031] Specifically, in this embodiment, the upper fixed pull plate 43 is used to realize the synchronous movement of the two motion guide rails 47. The upper ends of the two motion guide rails 47 are connected to the upper fixed pull plate 43, and the driving device is connected to the upper fixed pull plate 43. Thus, the driving device drives the upper fixed pull plate 43 to move up and down, thereby realizing the synchronous up and down movement of the two motion guide rails 47.

[0032] The lower ends of both motion guides 47 are connected to the lower fixed pull plate 48. The upper fixed pull plate 43 and the lower fixed pull plate 48 are also used to limit the movement of the drill bit assembly, that is, the drill bit assembly is limited between the upper fixed pull plate 43 and the lower fixed pull plate 48.

[0033] In one embodiment, such as Figure 5 As shown, each limiting guide rail 46 has a mating groove on the side away from the other limiting guide rail 46. Each mating groove extends vertically to both ends and passes through the corresponding limiting guide rail 46. Each moving guide rail 47 is fixedly connected with a mating guide rail 472 that mates with the mating groove.

[0034] As described above, the motion guide rail 47 can move up and down relative to the limiting guide rail 46. Specifically, each limiting guide rail 46 has a mating groove on the side away from the other limiting guide rail 46. Each mating groove extends to both the upper and lower ends and passes through the corresponding limiting guide rail 46. A mating guide rail 472 is fixedly connected to the corresponding side of each motion guide rail 47. The up and down movement of the two motion guide rails 47 is achieved by the movement of the mating guide rail 472 within the mating groove. As an alternative, the mating guide rail 472 can also be located on the side of each limiting guide rail 46 away from the other limiting guide rail 46, and the mating groove can be located on each motion guide rail 47. Similarly, the up and down movement of the two motion guide rails 47 is achieved by the movement of the mating guide rail 472 within the mating groove.

[0035] In one embodiment, such as Figure 5 As shown, the first chute 461 includes a horizontal chute 4611 whose length direction is parallel to the drilling direction of the drill bit assembly, and the second chute 471 includes a straight chute 4712. The straight chute 4712 and the horizontal chute 4611 have an acute angle between them. The driving device is used to drive the two motion guide rails 47 to move up and down, so as to drive the drill bit assembly to move into the formation, break the rock core and retract through the cooperation of the horizontal chute 4611 and the straight chute 4712.

[0036] Specifically, the first groove 461 includes a horizontal groove 4611, the length of which is parallel to the direction in which the drill bit 44 drills into the formation. This allows the drill bit assembly to gradually move closer to or further away from the formation by being propelled by the second groove 471 within the horizontal groove 4611. To ensure the drill bit assembly can smoothly extend from the side opening through the horizontal groove 4611, the side opening is located on the extension line of the horizontal groove 4611.

[0037] Secondly, the second chute 471 includes a straight chute 4712, which forms an acute angle with the horizontal chute 4611, such as 45 degrees or 30 degrees. The vertical movement of the straight chute 4712, driven by the drive device, propels the drill bit assembly within the horizontal chute 4611, enabling the drill bit assembly to drill into the formation or be retrieved. When the drill bit assembly retrieves a core sample, the drive device moves the drill bit assembly downwards to break off the core. Specifically, the drive device moves the guide rail 47 downwards, causing the side of the drill bit assembly in contact with the guide rail 47 to move downwards, while the other side of the drill bit assembly tilts upwards, thus breaking off the core.

[0038] In one embodiment, such as Figure 5 As shown, the first slide groove 461 also includes a first arc-shaped groove 4612, which is located at the end of the horizontal slide groove 4611 away from the side opening. The first arc-shaped groove 4612 communicates with the horizontal slide groove 4611. The second slide groove 471 also includes a second arc-shaped groove 4711, which is located at the end of the straight slide groove 4712 away from the side opening. The second arc-shaped groove 4711 communicates with the straight slide groove 4712. Second sliders are also fixedly connected to both sides of the drill bit assembly. Each limiting guide rail 46 is also provided with a second slider mating groove 462 that communicates with the horizontal slide groove 4611. The driving device is used to drive the two moving guide rails 47 to move so that the second slide groove 471 pushes the first slider through the first arc-shaped groove 4612, so that the second slider moves in the second slider mating groove 462 to realize the flipping of the drill bit assembly.

[0039] Specifically, taking a side opening on the left side and a linear slide 4712 tilting from the upper left to the lower right as an example, when the drive device moves the motion guide 47 upward until the first slider enters the second arc-shaped groove 4711 from the linear slide 4712, the first slider passes through the first arc-shaped groove 4612, and the second slider enters the second slider mating groove 462. The drive device continues to move the motion guide 47 upward, and the second arc-shaped groove 4711 pushes the first slider to move within the first arc-shaped groove 4612. Correspondingly, the second slider moves within the second slider mating groove 462 to achieve the rotation of the drill bit assembly. Finally, the axis of the drill bit assembly rotates to be parallel to the axis of the coring instrument. During drilling, the line connecting the first and second sliders is parallel to the horizontal direction, allowing the drill bit assembly to rotate 90 degrees.

[0040] In one embodiment, the first slider is a rhombus-shaped slider, one set of parallel surfaces of the rhombus-shaped slider contacts the two side walls of the horizontal slide 4611, and the other set of parallel surfaces of the rhombus-shaped slider contacts the two side walls of the straight slide 4712; the drill assembly includes a drill bit 44 and a hydraulic motor 45 connected to the drill bit 44, and both the first slider and the second slider are mounted on the hydraulic motor 45; the driving device includes a drilling hydraulic cylinder, and the piston rod of the drilling hydraulic cylinder is connected to the motion guide rail 47.

[0041] In this embodiment, the first slider is specifically a rhomboid slider, and the drill bit assembly specifically includes a drill bit 44 and a hydraulic motor 45, the hydraulic motor 45 being used to drive the drill bit 44 to rotate; the driving device includes a drilling hydraulic cylinder (corresponding to...). Figure 4 (G6) The piston rod of the drilling hydraulic cylinder is connected to the upper fixed pull plate 43. When the piston rod of the drilling hydraulic cylinder extends, it drives the upper fixed pull plate 43 and the motion guide rail 47 to move down accordingly. When the piston rod of the drilling hydraulic cylinder retracts, it drives the upper fixed pull plate 43 and the motion guide rail 47 to move up accordingly.

[0042] Furthermore, the mechanical section housing 41 of this embodiment is also equipped with a spacer insertion mechanism and a core detection mechanism. After drilling, the core is pushed into the core cylinder through the core channel. The core detection mechanism is used to perform real-time detection of the core inside the core cylinder. The detected core then passes through the core channel into the core cylinder of the core storage section 5 for storage. The spacer insertion mechanism pushes spacers into the core channel after the core pushing action. The spacers are used to physically distinguish cores from different layers.

[0043] In one embodiment, such as Figure 3 As shown, the hydraulic control sub 3 includes a hydraulic sub body 31, on which an upper push arm 32 and a reverse push arm 33 are provided. The pushing direction of the upper push arm 32 is opposite to that of the reverse push arm 33. The mechanical sub housing 41 is provided with a lower push arm 42, on which the pushing direction of the upper push arm 32 is the same as that of the lower push arm 42. The reverse push arm 33 can be operated independently to detach the coring instrument from the well wall.

[0044] Specifically, during coring operations, the upper push arm 32 and the reverse push arm 33 can be opened simultaneously to secure the coring instrument firmly to the well wall. At the same time, the upper push arm has a relatively large force to secure the coring instrument, preventing the coring instrument from moving up and down during coring and causing the drill bit 44 to get stuck. Furthermore, when the coring instrument is attached to the well wall, the reverse push arm 33 can be used alone to detach the instrument from the well wall, thus solving the problem of the coring instrument being stuck to the well wall and unable to be detached.

[0045] In one embodiment, the push arm 32 and the push back arm 33 have the same structure; the push back arm 33 includes a push back hydraulic cylinder composed of a push back cylinder body 331, a first piston rod 332 and a second piston rod 333, wherein the push back cylinder body 331 is sealed and slidably connected to the first piston rod 332, the first piston rod 332 has a through hole, the second piston rod 333 is sealed and slidably connected to the through hole, and the end of the second piston rod 333 extending out of the first piston rod 332 is fixedly connected to a push head 334. The push back hydraulic cylinder is connected to a hydraulic control unit, which is used to control the extension of the first piston rod 332 and the second piston rod 333 in the push back cylinder body 331, and to control the retraction of the first piston rod 332 and the second piston rod 333 in the push back cylinder body 331.

[0046] Specifically, the push arm 32 and the reverse push arm 33 have the same structure, differing only in their installation position and direction. Taking the reverse push arm 33 as an example, the reverse push arm 33 includes a reverse push cylinder 331, a first piston rod 332, a second piston rod 333, and a push head 334. When hydraulic oil is introduced into the rodless chamber of the reverse push cylinder 331, the first piston rod 332 and the second piston rod 333 gradually extend out of the reverse push cylinder 331, thereby enabling the push head 334 to extend and securely fix the coring instrument to the well wall or to detach the instrument from the well wall. When hydraulic oil is introduced into the rod chamber of the reverse push cylinder 331 again, the first piston rod 332 and the second piston rod 333 gradually retract into the reverse push cylinder 331, thereby enabling the reverse push arm 33 to retract.

[0047] Among them, the hydraulic control unit that reverses the thrust is the hydraulic cylinder G3, such as Figure 4 As shown, it includes hydraulic control directional valve NC-8, hydraulic control directional valve NO-9, hydraulic control check valve R3, hydraulic control check valve R4, and safety relief valve K6; wherein, hydraulic control directional valve NC-4 is a two-position three-normally shut-off hydraulic control directional valve, and hydraulic control directional valve NO-9 is a two-position three-normally open hydraulic control directional valve. When the hydraulic directional valves NO-9 and NC-8 are in their normal positions, high-pressure oil enters the control outlet (C port) through the high-pressure oil inlet (P port) of the hydraulic directional valve NO-9. The high-pressure oil at the control outlet enters the rod chamber of the thrust cylinder 331. At the same time, the high-pressure oil through the hydraulic directional valve NO-9 opens the hydraulic check valve R3, and the hydraulic oil in the rodless chamber of the thrust cylinder 331 returns to the oil tank through the hydraulic check valve R3, thereby retracting the first piston rod 332 and the second piston rod 333 in the thrust cylinder 331. As for the solenoid directional valve NC-8, part of the hydraulic oil in the rodless chamber of the thrust cylinder 331 flows back to the oil tank through the control outlet (C port) into the second oil port (R port).

[0048] When the hydraulic directional valves NO-9 and NC-8 switch simultaneously, high-pressure oil enters the control outlet (C port) through the high-pressure oil inlet (P port) of the hydraulic directional valve NC-8. The hydraulic oil at the control outlet (C port) enters the rodless chamber near the cylinder 331. At the same time, the high-pressure oil through the hydraulic directional valve NC-8 opens the hydraulic check valve R4, and the hydraulic oil in the rod chamber near the cylinder 331 returns to the oil tank through the hydraulic check valve R4. In addition, the high-pressure oil inlet (P port) of the hydraulic directional valve NO-9 is closed, and part of the hydraulic oil in the rod chamber near the cylinder 331 flows back to the oil tank through the control outlet (C port) into the second oil port (R port). In this way, the first piston rod 332 and the second piston rod 333 can be pushed out.

[0049] The safety relief valve K6 serves as an overpressure protection mechanism. Specifically, when the reverse thrust hydraulic cylinder remains inactive for an extended period, the hydraulic oil sealed within the hydraulic lines will thermally expand, causing the pressure to rise. When the pressure of the hydraulic oil rises to exceed the opening value of the safety relief valve K6, the safety relief valve K6 opens, and the hydraulic oil flows back to the oil tank through the safety relief valve K6 to achieve unloading.

[0050] at last, Figure 4 G1 is the downward-pushing hydraulic cylinder, G2 is the upward-pushing hydraulic cylinder, G4 is the partition hydraulic cylinder, G5 is the core-taking hydraulic cylinder, and G6 is the drilling hydraulic cylinder. Their operating principles are the same as those of the reverse-pushing hydraulic cylinder G3, and will not be repeated here. In this embodiment, the hydraulic control unit uses a hydraulically controlled directional valve structure, thereby reducing the number of electromagnetic directional valves used and improving the reliability of the core-taking instrument.

[0051] In one embodiment, such as Figure 2 As shown, the electronic subsection 1 includes an insulating outer shell 12, inside which are arranged several electronic frames 15. Each electronic frame 15 is used to fix a circuit board. Each electronic frame 15 has a heat-absorbing unit 14 at both ends. The length of the heat-absorbing unit 14 is determined by the heat generated by the circuit board on the adjacent electronic frame 15. A heat insulation sleeve 13 is arranged above the uppermost heat-absorbing unit 14 inside the insulating outer shell 12, and a heat-insulating filler 16 is arranged below the lowermost heat-absorbing unit 14 inside the insulating outer shell 12. An upper connector 11 is connected to the upper end of the insulating outer shell 12, and an electronic connector 17 is connected to the lower end of the insulating outer shell 12. The circuit board passes through the heat-insulating filler 16 and the heat-absorbing unit 14 and is connected to the electronic connector 17.

[0052] Specifically, the electronic sub-section 1 in this embodiment includes an insulated outer shell 12, which provides heat insulation and can withstand an environmental pressure of 140 MPa. The upper end of the insulated outer shell 12 is connected to an upper connector 11, and the lower end is connected to an electronic connector 17. The cavity formed by the insulated outer shell 12, the upper connector 11, and the electronic connector 17 is evacuated and used to house the electronic skeleton 15. The upper connector 11 is used to connect the electronic sub-section 1 to the upper structure; for example, the electronic sub-section 1 can be connected to a bridle or a temperature tension sub-section via the upper connector 11.

[0053] Furthermore, the electronic frame 15 comprises several units, each used to fix a circuit board. Each electronic frame 15 has a heat-absorbing unit 14 at both ends. The length of the heat-absorbing unit 14 is determined by the heat generation of the circuit board on the adjacent electronic frame 15. The heat-absorbing unit 14 includes a metal heat-absorbing agent shell containing heat-absorbing agent for storing heat. In this embodiment, the insulation outer shell 12 adopts a segmented, cross-arranged structure of heat-absorbing units 14 and electronic frames 15, which is beneficial for uniform heat distribution. Different lengths of heat-absorbing units 14 are configured according to the different heat generation of the circuit board, thereby ensuring a basically uniform internal temperature of the insulation outer shell 12.

[0054] Furthermore, the heat insulation filler 16 is made of a material with high thermal resistance, such as cotton wool, to isolate the internal heat of the heat insulation outer shell 12 from the external heat. The heat insulation sleeve 13 also serves to isolate the internal heat of the heat insulation outer shell 12 from the external heat. The electronic frame 15 is made of a material with low thermal resistance, thereby enabling faster and more uniform heat transfer and dissipation. In this embodiment, the electronic section 1 can ensure that the internal temperature of the thermos bottle does not exceed 150°C after 20 hours of continuous operation at 205°C, significantly improving the reliability of the circuit board.

[0055] In one embodiment, such as Figure 1 As shown, the balancing sub 2 is positioned between the electronic sub 1 and the hydraulic control sub 3. The balancing sub 2 is used to balance the internal hydraulic oil pressure of the instrument and the downhole formation mud pressure. In this embodiment, the balancing sub 2 is positioned between the electronic sub 1 and the hydraulic control sub 3. In specific implementations, it can also be positioned in other locations.

[0056] Again, such as Figure 6As shown, the balance section 2 includes a balance section outer shell 21, a balance cylinder 22 is disposed inside the balance section outer shell 21, and a moving piston 24 is disposed inside the balance cylinder 22. The moving piston 24 divides the space inside the balance cylinder 22 into a mud chamber 23 and an oil chamber. A piston tension spring 25, a moving rod 27, and a moving rod compression spring 26 are disposed inside the oil chamber. One end of the piston tension spring 25 is fixed to one end of the cylinder, and the other end of the piston tension spring 25 is connected to one side of the moving piston 24. One side of the moving piston 24 is also connected to one end of the moving rod compression spring 26, and the other end of the moving rod compression spring 26 is connected to one end of the moving rod 27. A displacement sensor 28 for measuring the displacement of the moving piston 24 is disposed at the other end of the moving rod 27. A limit structure is disposed on the other end of the moving rod 27, and a locking structure is also connected to one side of the moving piston 24. The moving piston 24 drives the moving rod to move through the cooperation of the locking structure and the limit structure.

[0057] Specifically, the balancing sub 2 includes a balancing sub housing 21, a balancing cylinder 22 disposed inside the balancing sub housing 21, and a moving piston 24 disposed inside the balancing cylinder 22. The moving piston 24 divides the space inside the balancing sub into a mud chamber 23 and an oil chamber that are isolated from each other. When the pressure inside the mud chamber 23 increases, the mud inside the mud chamber 23 pushes the moving piston 24 to move in the direction of compressing hydraulic oil. When the pressure inside the oil chamber increases, the oil inside the oil chamber pushes the moving piston 24 to move in the direction of compressing mud, thereby achieving the purpose of balancing the hydraulic oil pressure inside the instrument and the mud pressure in the downhole formation.

[0058] Furthermore, the balance short section 2 in this embodiment can also be used to detect the oil level of the centrifuge. Specifically, a displacement sensor 28 is provided at the other end of the moving rod. The displacement sensor 28 can measure the displacement of the moving piston 24, thereby determining the oil level of the centrifuge based on the displacement of the moving piston 24.

[0059] The balance short section 2 in this embodiment is equipped with a full-range oil level detection capability. During high-temperature and high-pressure operations, it can measure the expansion and compression of hydraulic oil in real time under high-temperature and high-pressure conditions, ensuring that the oil meets the operational requirements and improving the reliability of the coring instrument.

[0060] In one embodiment, the core storage section 5 includes a plurality of core tubes connected by threads. The core storage section 5 can be seated at the wellhead by a wellhead chuck. The uppermost core tube is connected to the connecting tube above it via a transition joint. The uppermost core tube is threadedly connected to the transition joint. A plurality of locking blocks are fixedly connected to the upper end of the transition joint. The lower end of the connecting tube has a locking groove that mates with the locking blocks. The transition joint and the connecting tube are connected by the locking blocks and the locking groove. A cotter pin is connected between the connecting tube and the transition joint.

[0061] Specifically, the core storage section 5 in this embodiment includes several core tubes connected by threads, for example, 80 or more core tubes, enabling core sampling operations to complete 80 or more core samples in one trip, thus improving core sampling efficiency. The core storage section 5, with its connected core tubes, can be seated at the wellhead via a wellhead chuck, and the core tubes can be arbitrarily lengthened, facilitating core tube assembly. It also allows for rapid connection between the core storage section 5 and the structure above it, reducing instrument deformation compared to existing technologies that require surface installation.

[0062] Furthermore, the uppermost core tube is threadedly connected to the transition joint, and the transition joint is connected to the upper connecting tube through a locking block and a locking groove. A cotter pin connects the transition joint and the connecting tube, which has the advantage of easy assembly.

[0063] It should be noted that, unless otherwise stated, the technical or scientific terms used in this application should have the ordinary meaning as understood by one of ordinary skill in the art to which this invention pertains.

[0064] Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly defined.

[0065] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; 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; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0066] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be covered within the scope of the claims and specification of the present invention. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. The present invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A rotating wellbore coring instrument, comprising an electronic sub, a balancing sub, a hydraulic control sub, a mechanical actuation sub, and a core storage sub, characterized in that, The mechanical actuation section includes a mechanical section housing, and a transmission device is provided inside the mechanical section housing. The transmission device is connected to the drill bit assembly. The transmission device is used to drive the drill bit assembly to drill into the formation, break the rock core, retract and flip under the drive of the drive device. After flipping, the axis of the drill bit assembly is parallel to the axis of the coring instrument. The mechanical section housing is provided with a side opening for the drill bit assembly to extend out. The electronic sub-section includes an insulated outer shell, within which are disposed a plurality of electronic frames. Each electronic frame is used to fix a circuit board, and each electronic frame has heat-absorbing units at both ends. The length of each heat-absorbing unit is determined by the heat generated by the circuit board on the adjacent electronic frame. A heat-insulating sleeve is disposed above the uppermost heat-absorbing unit in the insulated outer shell, and a heat-insulating filler is disposed below the lowermost heat-absorbing unit in the insulated outer shell. An upper connector is connected to the upper end of the insulated outer shell, and an electronic connector is connected to the lower end of the insulated outer shell. The circuit board passes through the heat-insulating filler and the heat-absorbing unit and connects to the electronic connector. The core storage section includes several core tubes connected by threads. The core storage section can be seated at the wellhead by a wellhead chuck. The uppermost core tube is connected to the connecting tube above it via a transition joint. The uppermost core tube is threadedly connected to the transition joint. Several locking blocks are fixedly connected to the upper end of the transition joint. The lower end of the connecting tube has a locking groove that mates with the locking blocks. The transition joint and the connecting tube are connected by locking blocks and locking grooves. A cotter pin connects the connecting tube and the transition joint.

2. The rotating wellbore coring instrument according to claim 1, characterized in that, The transmission device includes two parallel limiting guide rails, both of which are fixedly connected to the outer shell of the mechanical section. Each limiting guide rail has a first groove, and a moving guide rail is connected to the side of each limiting guide rail away from the other limiting guide rail. Each moving guide rail has a second groove. The drill bit assembly is disposed between the two limiting guide rails, and first sliders are fixedly connected to corresponding sides of the drill bit assembly. Each first slider passes through the corresponding first groove and extends into the second groove. Both moving guide rails are connected to the driving device, which drives the two moving guide rails to move up and down, so as to drive the drill bit assembly to drill into the formation, break the rock core, retract, and flip through the cooperation of the first and second grooves.

3. The rotating wellbore coring instrument according to claim 2, characterized in that, The upper ends of both motion guide rails are connected to the upper fixed pull plate, and the lower ends of both motion guide rails are connected to the lower fixed pull plate. The driving device is connected to the upper fixed pull plate so that the upper fixed pull plate is driven by the driving device to realize the up and down movement of the two motion guide rails.

4. The rotating wellbore coring instrument according to claim 2, characterized in that, Each of the limiting guide rails has a mating groove on the side away from the other limiting guide rail. Each mating groove extends vertically to both ends and passes through the corresponding limiting guide rail. Each moving guide rail is fixedly connected to a mating guide rail that mates with the mating groove.

5. The rotating wellbore coring instrument according to claim 2, characterized in that, The first chute includes a horizontal chute whose length direction is parallel to the drilling direction of the drill bit assembly. The second chute includes a straight chute. The straight chute and the horizontal chute have an acute angle between them. The driving device is used to drive the two motion guide rails to move up and down, so as to drive the drill bit assembly to move into the formation, break the rock core, and retract through the cooperation of the horizontal chute and the straight chute.

6. The rotating wellbore coring instrument according to claim 5, characterized in that, The first slide groove further includes a first arc-shaped groove, which is disposed at the end of the horizontal slide groove away from the side opening and is connected to the horizontal slide groove. The second slide groove further includes a second arc-shaped groove, which is disposed at the end of the straight slide groove away from the side opening and is connected to the straight slide groove. The two sides of the drill bit assembly are also fixedly connected to second sliders. Each of the limiting guide rails is also provided with a second slider mating groove that is connected to the horizontal slide groove. The driving device is used to drive the two motion guide rails to move so that the second slide groove pushes the first slider through the first arc-shaped groove, so that the second slider moves in the second slider mating groove to realize the flipping of the drill bit assembly.

7. The rotating wellbore coring instrument according to claim 6, characterized in that, The first slider is a rhombus-shaped slider, one set of parallel surfaces of the rhombus-shaped slider contacts the two side walls of the horizontal slide, and the other set of parallel surfaces of the rhombus-shaped slider contacts the two side walls of the straight slide; the drill assembly includes a drill bit and a hydraulic motor connected to the drill bit, and the first slider and the second slider are both mounted on the hydraulic motor; the driving device includes a drilling hydraulic cylinder, and the piston rod of the drilling hydraulic cylinder is connected to the motion guide rail.

8. The rotating wellbore coring apparatus according to any one of claims 1-7, characterized in that, The hydraulic control section includes a hydraulic section body, on which an upper push arm and a reverse push arm are provided. The pushing direction of the upper push arm is opposite to that of the reverse push arm. The outer shell of the mechanical section is provided with a lower push arm, on which the pushing direction of the upper push arm is the same as that of the lower push arm. The reverse push arm can be operated independently to detach the coring instrument from the well wall. The upward push arm and the reverse push arm have the same structure; the reverse push arm includes a reverse push hydraulic cylinder composed of a reverse push cylinder body, a first piston rod, and a second piston rod, wherein the first piston rod is slidably and sealed within the reverse push cylinder body, the first piston rod has a through hole, the second piston rod is slidably and sealed within the through hole, and a push head is fixedly connected to one end of the second piston rod extending out of the first piston rod. The reverse push hydraulic cylinder is connected to a hydraulic control unit, which is used to control the extension of the first piston rod and the second piston rod within the reverse push cylinder body, and to control the retraction of the first piston rod and the second piston rod within the reverse push cylinder body.

9. The rotating wellbore coring instrument according to claim 1, characterized in that, The balancing short section is disposed between the electronic short section and the hydraulic control short section. The balancing short section includes a balancing short section housing, within which a balancing cylinder is disposed. A moving piston is disposed within the balancing cylinder, dividing the space within the balancing cylinder into a mud chamber and an oil chamber. A piston tension spring, a moving rod, and a moving rod compression spring are disposed within the oil chamber. One end of the piston tension spring is fixed to one end of the cylinder, and the other end of the piston tension spring is connected to one side of the moving piston. One side of the moving piston is also connected to one end of the moving rod compression spring, and the other end of the moving rod compression spring is connected to one end of the moving rod. A displacement sensor for measuring the displacement of the moving piston is disposed at the other end of the moving rod, and a limit structure is disposed on the other end of the moving rod. A locking structure is also connected to one side of the moving piston. The moving piston drives the moving rod to move through the cooperation of the locking structure and the limit structure.

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