A core ejector for a rotary corer

Abstract

The application discloses a core length measuring mechanism of a rotating corer, and belongs to the technical field of well logging and perforating operations. The core length measuring mechanism can solve the problems of frequent missing measurement or inaccurate measurement of the core length measuring mechanism of the rotating corer when the core length measuring mechanism is unstable during well logging, and the problems of difficult complete and accurate determination of the positions of the strata corresponding to each core, which affect the efficiency of the operation and the analysis and judgment of the information of the strata in the later period. The mechanism is provided with a poking piece mechanism, a poking piece bin and a core length measuring mechanism. The stable core length measuring mechanism combined with the poking piece mechanism can better determine the strata depth position information of each core, and better solve the instability and uncertainty of the prior art.

Description

Technical Field

[0001] This invention belongs to the field of oil well logging perforation operation technology, specifically relating to a core length mechanism for a rotating core sampler. Background Technology

[0002] When using rotary corers for coring in downhole operations, it is essential to accurately obtain core samples from specific formation depths, requiring precise identification and marking of each core sample taken during the operation. Currently, rotary corers only have core length monitoring capabilities during logging operations, which can only determine whether a core has been retrieved and its length. Furthermore, instability in the core length mechanism often leads to missed or inaccurate measurements. With all cores stacked together, it is difficult to accurately determine the formation location of each core, impacting operational efficiency and even hindering subsequent formation information analysis. Summary of the Invention

[0003] In order to overcome the shortcomings of the prior art, the present invention aims to provide a core length mechanism for a rotary core sampler, which solves the problems of instability of the core length mechanism in current rotary wellbore core samplers during logging operations, often resulting in missed or inaccurate measurements, and the difficulty in accurately determining the location of the formation corresponding to each core when the cores are stacked together, thus affecting the efficiency of the operation and the subsequent analysis and judgment of formation information.

[0004] To achieve the above objectives, the present invention employs the following technical solution:

[0005] This invention discloses a core lengthening mechanism for a rotary core extractor, comprising a lower body, an outer shell, a core lengthening mechanism, a core lengthening mechanism, and a core storage cylinder; the direction of the wellhead is upward and the direction of the bottom of the well is downward; the lower end of the lower body is connected to the outer shell, and the interiors of the lower body and the outer shell are hollow and interconnected;

[0006] The lower body is provided with a paddle chamber, a core length mechanism and a paddle mechanism, one end of the paddle chamber and the paddle mechanism protruding from the upper surface of the lower body and fitting and fixed to the upper surface of the lower body.

[0007] The core reservoir is located inside the outer shell on one side, and the inlet of the core reservoir is fixed to the lower end of the lower body; the paddle chamber, core lengthening mechanism, and paddle mechanism are interposed inside the outer shell on the other side, and penetrate the lower body and the interior of the outer shell; the paddle chamber, core lengthening mechanism, and paddle mechanism are fixed inside the lower body; the core lengthening mechanism is associated with the paddle mechanism.

[0008] Furthermore, a pressure cap is provided on the side of the upper end of the lower body; the pressure cap is connected and fixed to the side of the upper end of the lower body by a number of screws M5; a protective pad is provided on the pressure cap; the outer shell is fixedly connected to the lower end of the lower body by a number of countersunk screws M10 and a number of positioning screws M6.

[0009] Furthermore, the cardiac extension mechanism includes a support hook, a cable guide assembly, a support slide, a coiled pin, a set screw M3, a mounting base, a first screw M4, an O-ring 2-007, and a potentiometer; the support hook is connected and fixed to the support slide via the coiled pin; the support slide and the potentiometer are connected and fixed via the set screw M3, and the potentiometer and the mounting base are fixedly connected via the first screw M4; the potentiometer has a cable guide assembly at its tail end; a sealing ring is provided on the cable guide assembly; an O-ring 2-007 is also provided at the connection between the potentiometer and the mounting base; the mounting base and the lower body are fixedly connected via several screws.

[0010] Furthermore, the paddle mechanism includes a rotating disk, a rotating shaft, a guide pin, a sealing end cap, and a guide rail shaft; the rotating disk protrudes from the upper part of the lower body, is fixedly attached to the upper surface of the lower body, and is connected to the rotating shaft located inside the lower body via a spline; the rotating shaft is connected to the guide rail shaft via a guide pin; the sealing end cap is disposed at the lower end of the guide rail shaft; the rotating shaft is fixedly connected to the lower body via a positioning pin.

[0011] Furthermore, the guide shaft is also provided with a spiral groove with a 66° rotation angle, and is connected to the rotating shaft through a guide pin; the guide shaft is also provided with a rotating fixing key, which is positioned in conjunction with the keyway of the body; a push plate is also fixedly provided on the guide shaft, and screws M4 and nuts M4 are fixed on the push plate; a piston is also provided on the guide shaft.

[0012] Furthermore, the heart-lengthening mechanism is associated with the paddle mechanism via a push plate.

[0013] Furthermore, the paddle magazine includes a paddle, a spring, a paddle cylinder, and a screw plug that are paddled into the reservoir by a rotating disc; the paddle cylinder is fixedly connected to the lower body; the upper part of the paddle cylinder protrudes from the upper surface of the lower body, the paddle is placed inside the upper part of the paddle cylinder, the spring is placed inside the lower part of the paddle cylinder, one end of the spring is in contact with the paddle, and the end of the spring that is not in contact with the paddle is provided with a screw plug; the screw plug is located at the lower part of the paddle cylinder.

[0014] Furthermore, the upper part of the paddle cylinder is also provided with a plug, which is located on the upper surface of the cap.

[0015] Furthermore, the lower body is also provided with an oil tank circuit for transmitting the wires of the potentiometer.

[0016] Furthermore, the lower body is also provided with a hydraulic oil circuit for controlling the piston movement of the guide shaft.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] This invention discloses a core length measurement mechanism for a rotating coring instrument. It comprises a core length measurement mechanism and a core storage chamber. Each core drilling operation involves inserting a core into the storage chamber, recording the results of each core extraction. The core is moved aside for recording. When the instrument retracts and pushes the core back in, the core length measurement mechanism returns to its initial position, completing one cycle. Furthermore, the core length measurement mechanism has been optimized and redesigned to better address this issue. The stable core length measurement mechanism, combined with the core length measurement mechanism, allows for better determination of the formation depth and location information of each core, effectively resolving the instability and uncertainty of existing technologies.

[0019] Furthermore, the paddle mechanism links the paddle mechanism's action with the heart length measurement mechanism via a push plate. When the heart length is measured after the core is retrieved, the push plate separates from the support hook to measure the heart length. When the instrument drills to retrieve the core, the push plate pushes the support hook back to the initial measurement position.

[0020] Furthermore, the paddles are pre-tensioned in the paddle magazine by springs with sufficient travel. Each time a paddle is pulled out, it pushes out the next paddle. The paddle mechanism uses hydraulic oil to make the guide shaft piston reciprocate, thereby driving the rotating shaft to reciprocate and realize the paddle action. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the core length-shifting mechanism of the rotating core extractor of the present invention;

[0022] Figure 2 for Figure 1 AA cross-section view;

[0023] Figure 3 for Figure 1 BB cross-section;

[0024] Figure 4 for Figure 2 EE cross-section;

[0025] Figure 5 for Figure 4 GG cross-section;

[0026] Figure 6 This is a schematic diagram of the structure of the cardiac extension mechanism of the present invention.

[0027] The components are: 1-Screw M5; 2-Protective pad; 3-Pressure cap; 4-Lower body; 5-Outer shell; 6-Core storage cylinder; 7-Core length mechanism; 71-Bracket hook; 72-Cable guide assembly; 73-Support slide; 74-Coil pin; 75-Setting screw M3; 76-Mounting base; 77-First screw M4; 78-O-ring 2-007; 79-Polypotentiometer; 8-Push plate; 9-Screw M4; 10-Nut M4; 11-Screw; 12-Plug; 13-Pulley; 14-Spring; 15-Pulley cylinder; 16-Plug; 17-Rotating shaft; 18-Guide rail shaft; 19-Guide pin; 20-Sealing end cap; 21-Rotating disk; 22-Positioning pin; 23-Counterhead screw M10; 24-Positioning screw M6. Detailed Implementation

[0028] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0029] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0030] This invention discloses a core length measuring mechanism for a rotating core extractor, comprising a lower body 4, on which a core length measuring mechanism 7 and a core length measuring device are arranged sequentially from top to bottom. The core length measuring device 7 is installed in the core length measuring device and pre-tightened by a spring 14. The support hook 71 of the core length measuring device 7 is associated with the core length measuring device 7 through a push plate 8. After the core length measurement is completed, the core length measuring device 7 is reset to its initial position. A 1.5-meter core storage cylinder 6 is connected to the lower end of the lower body 4.

[0031] In the core length mechanism 7, the core length mechanism 7 is connected to the potentiometer 79 via the support hook 71 and the support slide 73. When the core pushes the support hook 71, the core length information can be measured by the change of the potentiometer 79. The tail of the potentiometer 79 is provided with a wire tube. The wire of the potentiometer 79 is transmitted to the lower body 4 through the sealing of the wire tube and connected to the internal oil tank of the instrument, thereby isolating the external well fluid and pressure.

[0032] The paddle mechanism consists of a rotating disk 21, a rotating shaft 17, a guide pin 19, a sealing end cap 20, and a guide shaft 18. The rotating disk 21 and the rotating shaft 17 are connected by a spline. The front end of the rotating shaft 17 is provided with a positioning pin 22. The rotating shaft 17 is provided with a guide pin 19, which is connected to the guide shaft 18. The guide shaft 18 is provided with a piston, which rotates the rotating shaft 17 by reciprocating motion. The end of the guide shaft 17 is provided with a sealing end cap 20 to isolate external well fluid.

[0033] The upper end of the lower body 4 is also provided with a pressure cap 3 to protect and limit the rotating disk 21. The upper end of the pressure cap 3 is provided with a PTFE protective pad 2. The lower body is also provided with a deep groove for better control of the support hook 71. The guide shaft 18 is provided with a push plate 8 connected by screws. At the same time, the push plate 8 is provided with a limit screw. Before core drilling, the support hook 71 is pressed up by the limit screw. When the instrument performs drilling action, the guide shaft drives the push plate 8 to move upward, thereby driving the support hook 71 back to the initial position. The outer shell 5 is fixedly connected to the lower end of the lower body 4 by several countersunk screws M1023 and several positioning screws M624 to protect the internal mechanism. The lower body 4 is provided with three hydraulic oil circuits. One is an oil tank oil circuit for transmitting the core length potentiometer wire. The other two are hydraulic oil circuits for controlling the piston movement of the guide shaft. One is connected to the instrument support arm recovery oil circuit and the other is connected to the core drilling oil circuit. All internal hydraulic oil parts of the instrument are separated from the external well fluid by sealing rings.

[0034] The present invention will now be described in further detail with reference to the accompanying drawings:

[0035] like Figure 1 As shown, the core length mechanism of a rotating core extractor of the present invention includes a pressure cap 3 and a protective pad 2 installed and fixed on the pressure cap 3; the pressure cap 3 is connected and fixed to the lower body 4 by four screws M51; the outer shell 5 is fixedly connected to the lower body 4 by four countersunk screws M1023; the core length component 7 is connected and fixed to the lower body 4 by two screws 11; the push plate 8 is fixed to the guide rail shaft 18 by screws; and screws M49 and nuts 10 are fixed on the push plate.

[0036] The lower body 4 is mainly used to support and install other functional components. The lower end is connected to the core storage cylinder 6 and the outer shell 5 for storing rock cores. Secondly, the lower body 4 has hydraulic oil circuits inside to control the action of the paddle mechanism. The core length mechanism 7 is installed on the lower body 4 by two screws.

[0037] The push plate 8 is fixed to the guide shaft 18 by screws. At the same time, screw M49 and nut M410 are fixed to the push plate 8 to control the position and movement of the support hook 71. When the core drilling pusher mechanism moves the pusher 13, the guide shaft 18 drives the push plate 8 to push the support hook 71 back to the initial position. When the core is pushed back by the retracting arm, the guide shaft 18 drives the push plate 8 to move backward and separate from the support hook 71. At the same time, screw M49 presses down on the support hook 71 to make it tilt up, so that the core pushes the support hook 71 to measure the core length.

[0038] like Figure 2 As shown, the rotary disk 21 is connected to the rotary shaft 17 via a spline. When the support arm is retracted, the rotary disk 21 is in the position of the paddle hole. When the instrument performs the core drilling action, the rotary shaft 17 drives the rotary disk 21 to move the paddle 13 to the core storage cylinder 6 under the drive of the guide shaft 18. When the arm is retracted and the core is pushed, the rotary disk 21 returns to the initial position to complete one cycle.

[0039] like Figure 3 As shown, for the protection of internal parts, the lower part of the lower body 4 is connected to the outer shell 5, which is connected and fixed to the lower body by four countersunk screws M1023 and two positioning screws M624.

[0040] like Figure 4 As shown, a plug 12 is provided on the pressure cap to facilitate cleaning and maintenance of the paddle chamber; the paddle cylinder 15 is threadedly connected and fixed to the lower body 4, and the paddle 13 is placed in the paddle chamber. By using a spring 14 with sufficient stroke and a screw plug 16 for pre-tightening, each paddle will push out the next paddle, ensuring the continuity of the paddle action.

[0041] The guide shaft 18 is provided with a spiral groove with a 66-degree rotation angle, and is connected to the rotating shaft 17 through the guide pin 19, so that the rotating shaft 17 rotates when the guide shaft 18 moves in axial linear motion. The guide shaft 18 is provided with a rotation fixing key that cooperates with the keyway of the lower body 4 for positioning, ensuring that it can only move in axial linear motion. The guide shaft 18 is also provided with a piston that cooperates with the oil passage provided in the lower body 4 to complete the motion control of the guide shaft 18. At the same time, the lower end of the guide shaft 18 is also provided with a sealing end cover 20 for oil passage sealing and guide shaft limit.

[0042] like Figure 5As shown, the axial fixation of the rotating shaft 17 is achieved by providing a groove on the rotating shaft, and simultaneously connecting it to the lower body 4 through two positioning pins 22, ensuring that the rotating shaft 17 rotates when the guide shaft 18 moves axially, making the action unique and reliable.

[0043] like Figure 6 As shown, the core component 7 consists of a bracket hook 71, a conduit component 72, a support slide 73, a coiled pin (3x12) 74, a set screw M375, a mounting base 76, a first screw M477, an O-ring 2-00778, and a potentiometer 79.

[0044] The bracket hook 71 is connected and fixed to the support slide 73 by a coiled pin (3x12) 74. The potentiometer 79 is fixedly connected to the mounting base 76 by two first screws M477. The support slide 73 is connected and fixed to the potentiometer 79 by a set screw M375. The potentiometer 79 has a cable guide component 72 at its tail end. The cable guide has a sealing ring and is fixed by a nut. Similarly, an O-ring 2-00778 is also provided at the connection between the potentiometer 79 and the mounting base 76. This structure is designed to ensure that the potentiometer 79 is completely sealed in the hydraulic oil and isolated from the external environment while transmitting and receiving the cable. The movement of the bracket hook 71 will directly cause the potentiometer 79 to change position and measure the length of the rock core.

[0045] The specific implementation process of the rotating heart extractor's throttle mechanism disclosed in this invention mainly includes the following steps:

[0046] First, when the instrument is in the initial state of the support arm retracted, the rotary disk 21 of the lever mechanism is in the lever hole position under the action of the arm retraction hydraulic oil, and the head of the support hook 71 of the core length component 7 is raised under the action of the push plate screw M49. After the instrument extends the arm, it performs the core drilling action. At this time, the guide rail shaft 18 drives the rotary disk 21 to push the lever 13 into the core storage cylinder 6 under the action of the drilling hydraulic oil. At the same time, under its action, the push plate 8 drives the support hook 71 back to the initial position. After the core is retrieved, when the arm is retracted and the core is pushed, the guide rail shaft 18 drives the rotary disk 21 back to the initial position under the action of the arm retraction hydraulic oil. At the same time, under its action, the push plate screw M49 raises the head of the support hook 71. When the core is pushed into the core storage cylinder 6, it will push the support hook 71 to measure the core length information. After the instrument is brought out of the well, the core storage cylinder 6 is removed. The specific formation depth position information of each core is determined according to the position information of the lever 13 and the core length information of the core.

[0047] The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made to the technical solution based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

Claims

1. A core length-shifting mechanism for a rotating core extractor, characterized in that, It includes a lower body (4), an outer shell (5), a paddle chamber, a core length mechanism (7), a paddle mechanism, and a core storage cylinder (6); the direction of the wellhead is upward and the direction of the bottom of the well is downward; the lower end of the lower body (4) is connected to the outer shell (5), and the interiors of the lower body (4) and the outer shell (5) are hollow and interconnected; The lower body (4) is provided with a paddle chamber, a core length mechanism (7) and a paddle mechanism. One end of the paddle chamber and the paddle mechanism protrudes from the upper surface of the lower body (4) and is attached and fixed to the upper surface of the lower body (4). The core storage cylinder (6) is located on one side inside the outer shell (5), and the inlet of the core storage cylinder (6) is fixed to the lower end of the lower body (4); the paddle chamber, core length mechanism (7) and paddle mechanism are interposed on the other side inside the outer shell (5) and penetrate the interior of the lower body (4) and the outer shell (5); the paddle chamber, core length mechanism (7) and paddle mechanism are fixed inside the lower body (4); the core length mechanism (7) is associated with the paddle mechanism; The cardiac extension mechanism (7) includes a support hook (71), a cable guide component (72), a support slide (73), a coil pin (74), a set screw M3 (75), a mounting base (76), a first screw M4 (77), an O-ring 2-007 (78), and a potentiometer (79). The support hook (71) is connected and fixed to the support slide (73) via the coil pin (74). The support slide (73) is connected and fixed to the potentiometer (79) via the set screw M3 (75). The potentiometer (79) is fixedly connected to the mounting base (76) via the first screw M4 (77). The potentiometer (79) has a cable guide component (72) at its tail. The cable guide component (72) has a sealing ring on its cable guide. An O-ring 2-007 (78) is also provided at the connection between the potentiometer (79) and the mounting base (76). The mounting base (76) is fixedly connected to the lower body (4) via several screws (11). The paddle mechanism includes a rotating disk (21), a rotating shaft (17), a guide pin (19), a sealing end cap (20), and a guide rail shaft (18). The rotating disk (21) protrudes from the upper end of the lower body (4), is fixed to the upper surface of the lower body (4), and is connected to the rotating shaft (17) located inside the lower body (4) by a spline. The rotating shaft (17) is connected to the guide rail shaft (18) by the guide pin (19). The sealing end cap (20) is located at the lower end of the guide rail shaft (18). The rotating shaft (17) is fixedly connected to the lower body (4) by a positioning pin (22). The heart length mechanism (7) is associated with the paddle mechanism via a push plate (8).

2. The core length-shifting mechanism of a rotating core extractor according to claim 1, characterized in that, The lower body (4) has a pressure cap (3) on its upper side; the pressure cap (3) is connected and fixed to the upper side of the lower body (4) by a number of screws M5 (1); the pressure cap (3) has a protective pad (2); the outer shell (5) is fixedly connected to the lower end of the lower body (4) by a number of countersunk screws M10 (23) and a number of positioning screws M6 (24).

3. The core length-shifting mechanism of a rotating core extractor according to claim 1, characterized in that, The lower body (4) is also provided with an oil tank circuit for transmitting the wires of the potentiometer (79).

4. The core length-shifting mechanism of a rotating core extractor according to claim 1, characterized in that, The lower body (4) is also provided with a hydraulic oil circuit for controlling the piston movement of the guide shaft (18).

5. The core length-shifting mechanism of a rotating core extractor according to claim 1, characterized in that, The guide shaft (18) is also provided with a spiral groove with a 66° rotation angle, and is connected to the rotating shaft (17) through a guide pin (19); the guide shaft (18) is also provided with a rotating fixing key, which is positioned in conjunction with the keyway of the body (4); a push plate (8) is also fixedly provided on the guide shaft (18), and a screw M4 (9) and a nut M4 (10) are fixed on the push plate (8); a piston is also provided on the guide shaft (18).

6. The core length-shifting mechanism of a rotating core extractor according to claim 1, characterized in that, The paddle chamber includes a paddle (13) that is pushed into the reservoir (6) by the rotating disc (21), a spring (14), a paddle cylinder (15), and a screw plug (16); the paddle cylinder (15) is fixedly connected to the lower body (4); the upper part of the paddle cylinder (15) is exposed on the upper surface of the lower body (4), the paddle (13) is placed in the upper part of the paddle cylinder (15), the spring (14) is placed in the lower part of the paddle cylinder (15), one end of the spring (14) is in contact with the paddle (13), and the end of the spring (14) that is not in contact with the paddle (13) is provided with a screw plug (16); the screw plug (16) is located in the lower part of the paddle cylinder (15).

7. The core length-shifting mechanism of a rotating core extractor according to claim 6, characterized in that, The upper part of the paddle cylinder (15) is also provided with a plug (12), which is located on the upper surface of the cap (3).

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