Electrically-actuated back-up wrench for top-driven drilling device

Abstract

The invention discloses an electric actuating back-up wrench for a top driving well drilling device. The electric actuating back-up wrench comprises a driving unit, a pushing unit, a back-up wrench assembly, a front back-up wrench assembly and a back-up wrench cylinder body, the driving unit is in transmission connection with the pushing unit, and the driving unit and the pushing unit are both mounted on the back-up tong cylinder body; one end of the front back-up wrench assembly is hinged to the back-up wrench cylinder body, and the other end of the front back-up wrench assembly is detachably connected with the back-up wrench cylinder body. The back clamp assembly is connected to the pushing end of the pushing unit. The pushing unit is used for pushing the back clamp assembly to move towards the front back clamp assembly. Clamping and loosening of the back-up wrench are achieved through the driving pushing unit, no hydraulic oil exists inside, the problem of environmental pollution caused by leakage due to sealing failure does not need to be worried about, the structure is simplified, and driving is reliable; the driving unit remarkably improves the operation precision, the environmental adaptability and the reliability of the top-drive back-up wrench through electric-mechanical direct-drive transmission; compared with traditional hydraulic drive, the hydraulic drive device has the advantage of conforming to the trend of electric and automatic development of drilling equipment.

Description

Technical Field

[0001] The present invention belongs to the technical field of fixtures, and particularly relates to an electric actuated back-up tong for a top drive drilling device. Background Art

[0002] As a key component, the back-up tong of a top drive drilling device directly affects the efficiency of drill pipe make-up and break-out and the operation safety. Traditional back-up tongs mostly adopt a hydraulic drive system, which has the risk of hydraulic oil leakage, and the complex hydraulic pipelines result in high maintenance costs. For example, the back-up tong relies on a hydraulic cylinder to push a piston to clamp, and the sealing parts need to be frequently replaced to prevent freezing failures in winter. The hydraulic system needs to be additionally equipped with an oil pump and pipelines, increasing the equipment weight and failure points; the response delay of the hydraulic system easily leads to out-of-control clamping force and causes damage to drill pipe threads.

[0003] Therefore, there is an urgent need for an electric actuated back-up tong with a simple structure and reliable drive to improve drilling efficiency and equipment reliability. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide an electric actuated back-up tong for a top drive drilling device in view of the above deficiencies in the prior art. The back-up tong uses a drive pushing unit to realize clamping and releasing, has no hydraulic oil inside, does not need to worry about environmental pollution problems caused by leakage due to seal failure, and has a simplified structure and reliable drive.

[0005] To solve the above technical problem, the technical solution adopted by the present invention is: an electric actuated back-up tong for a top drive drilling device, including a drive unit, a pushing unit, a rear back-up tong assembly, a front back-up tong assembly and a back-up tong cylinder block; the drive unit and the pushing unit are in transmission connection, and both the drive unit and the pushing unit are installed on the back-up tong cylinder block; one end of the front back-up tong assembly is hinged to the back-up tong cylinder block, and the other end is detachably connected to the back-up tong cylinder block; the rear back-up tong assembly is connected to the pushing end of the pushing unit; the pushing unit is used to push the rear back-up tong assembly to move towards the front back-up tong assembly.

[0006] In the above electric actuated back-up tong, the pushing unit includes a ball screw and a ball nut used in cooperation with the ball screw, and the ball nut is in transmission connection with the drive unit;

[0007] The ball nut is supported inside the back-up tong cylinder block; the front end of the ball screw is detachably connected to a push rod, and the front end of the push rod is connected to the rear back-up tong assembly.

[0008] In the above electric actuated back-up tong, the drive unit includes a servo motor and a planetary gear reducer, the servo motor and the planetary gear reducer are in transmission connection, and a driving bevel gear is installed on the front output shaft of the planetary gear reducer;

[0009] The front end of the ball nut is provided with a driven bevel gear, and the driving bevel gear meshes with the driven bevel gear.

[0010] For the above-mentioned electric actuated back clamp, the servo motor is installed above the planetary gear reducer, and the planetary gear reducer is installed on the back clamp cylinder block through a flange seat.

[0011] For the above-mentioned electric actuated back clamp, the upper part of the driving bevel gear is of a tubular structure, the tubular structure is sleeved on the front end output shaft of the planetary gear reducer, and the tubular structure is fixed by a driving lock nut.

[0012] The tubular structure and the flange seat are supported by tapered roller bearings.

[0013] For the above-mentioned electric actuated back clamp, the ball nut is installed inside the back clamp cylinder block through the support of a thrust tapered roller bearing.

[0014] For the above-mentioned electric actuated back clamp, there is a shoulder on the inner wall of the back clamp cylinder block, there is one thrust tapered roller bearing on each side of the shoulder, a driven lock nut is installed at the rear end of the ball nut, and the two thrust tapered roller bearings support between the driven lock nut and the driven bevel gear.

[0015] For the above-mentioned electric actuated back clamp, a back plate flange is detachably installed at the rear end of the back clamp cylinder block, a limit groove is provided on the inner side of the back plate flange, a plug plate is detachably installed at the rear end of the ball screw, and the plug plate is matched with the limit groove.

[0016] For the above-mentioned electric actuated back clamp, the inner side of the rear section of the ball nut is a limit channel for the plug plate to slide back and forth.

[0017] For the above-mentioned electric actuated back clamp, at least two guiding keys are symmetrically arranged on the outer diameter of the push rod, a sealing seat is provided at the front end of the back clamp cylinder block, and guiding key grooves matched with the guiding keys of the push rod are provided on the sealing seat.

[0018] For the above-mentioned electric actuated back clamp, a sealing ring groove is provided at the front end of the sealing seat, a sealing support assembly is installed in the sealing ring groove, and the sealing support assembly is used for sealing the gap between the push rod and the sealing seat and supporting the push rod.

[0019] For the above-mentioned electric actuated back clamp, the back clamp cylinder block is connected with the lifting torque arm, and a rectangular flat key is arranged between the back clamp cylinder block and the lifting torque arm.

[0020] For the above-mentioned electric actuated back clamp, the driving unit is parallel to the lifting torque arm, and the driving unit is installed in front of the lifting torque arm.

[0021] The selection of the installation position of the drive unit takes into account the requirements of structural compactness, high heat dissipation efficiency, and environmental adaptability. Moreover, the position selection overcomes multi-objective constraint problems (such as the conflict between heat dissipation and dust prevention) and dynamic working condition adaptation problems (such as the moving requirements of the drilling rig).

[0022] Compared with the prior art, the present invention has the following advantages: By replacing the traditional hydraulic system with a drive unit and a pushing unit, problems such as oil leakage pollution and oil temperature sensitivity of the hydraulic system are solved, and at the same time, the structural design is simplified. The detachable connection structure of the front back-up tong assembly facilitates the maintenance and replacement of components. The pushing design of the back back-up tong assembly combined with the ball screw drive realizes the precise control of the clamping force. The overall structure is compact, meeting the automation requirements of drilling equipment.

[0023] The drive unit adopts a combination of a servo motor and a planetary gear reducer, transmits power through a ball screw, and combines the closed-loop feedback system of the servo motor to achieve real-time and precise adjustment of the clamping force.

[0024] The planetary gear reducer converts the high speed of the servo motor into a high torque output, and the transmission efficiency can reach more than 95%. Compared with the hydraulic drive system, electric energy is directly converted into mechanical energy, which can greatly save energy.

[0025] The drive unit uses an electric-motor direct drive transmission and a high-rigidity integrated structure, and combines intelligent control algorithms during use, which can significantly improve the operation accuracy, environmental adaptability, and reliability of the top drive back-up tong. Compared with the traditional hydraulic drive, its technical advantages conform to the development trend of drilling equipment towards electrification and automation.

[0026] The technical solution of the present invention will be further described in detail below with reference to the drawings and embodiments. Brief Description of the Drawings

[0027] Figure 1 is a schematic structural diagram of the present invention.

[0028] Figure 2 is Figure 1 a schematic structural diagram after the back-up tong is opened.

[0029] Figure 3 is Figure 1 a schematic vertical sectional structure diagram of...

[0030] Figure 4 is a schematic horizontal sectional structure diagram of the back-up tong cylinder.

[0031] Description of the Reference Numerals:

[0032] 1—Servo motor; 2—Planetary gear reducer; 3—Active locking nut;

[0033] 4—Tapered roller bearing; 5—Active bevel gear; 6—Sealing seat;

[0034] 7 - Push rod; 8 - Rear back-up tong assembly; 9 - Sealing support assembly;

[0035] 10 - Lifting torque arm; 11 - Rectangular flat key; 12 - Back-up tong cylinder block;

[0036] 13 - Thrust tapered roller bearing; 14 - Driven lock nut; 15 - Ball screw;

[0037] 16 - Plug plate; 17 - Back plate flange; 18 - Ball nut;

[0038] 19 - Driven bevel gear; 20 - Flange seat; 21 - Front back-up tong assembly;

[0039] 22 - Guide key; 23 - Pin shaft. Detailed implementation manner

[0040] As Figure 1 — Figure 4 shown, an electric actuated back-up tong for a top drive drilling device includes a driving unit, a pushing unit, a rear back-up tong assembly 8, a front back-up tong assembly 21 and a back-up tong cylinder block 12; the driving unit and the pushing unit are in transmission connection, and both the driving unit and the pushing unit are installed on the back-up tong cylinder block 12; one end of the front back-up tong assembly 21 is hinged to the back-up tong cylinder block 12, and the other end is detachably connected to the back-up tong cylinder block 12, and here a pin shaft 23 is used for connection; the rear back-up tong assembly 8 is connected to the pushing end of the pushing unit; the pushing unit is used for pushing the rear back-up tong assembly 8 to move towards the front back-up tong assembly 21.

[0041] In this embodiment, the pushing unit includes a ball screw 15 and a ball nut 18 used in cooperation with the ball screw 15, and the ball nut 18 is in transmission connection with the driving unit; the ball nut 18 is supported inside the back-up tong cylinder block 12; the front end of the ball screw 15 is detachably connected to a push rod 7, and the front end of the push rod 7 is connected to the rear back-up tong assembly 8.

[0042] It should be noted that the transmission efficiency of the ball screw 15 is as high as over 90%, which can significantly reduce energy loss; the modular design of the push rod 7 facilitates quick disassembly and assembly during maintenance. This structure is more suitable for high-precision clamping requirements compared with a hydraulic cylinder.

[0043] In this embodiment, the driving unit includes a servo motor 1 and a planetary gear reducer 2. The servo motor 1 is drivingly connected to the planetary gear reducer 2. A driving bevel gear 5 is installed on the front output shaft of the planetary gear reducer 2. The front end of the ball nut 18 has a driven bevel gear 19, and the driving bevel gear 5 meshes with the driven bevel gear 19. The servo motor 1 is installed above the planetary gear reducer 2, and the planetary gear reducer 2 is installed on the back clamp cylinder block 12 through a flange seat 20. The upper part of the driving bevel gear 5 is a tubular structure, and the tubular structure is sleeved on the front output shaft of the planetary gear reducer 2, and the tubular structure is fixed by a driving lock nut 3. The tubular structure and the flange seat 20 are supported by a tapered roller bearing 4.

[0044] It should be noted that the structure of the servo motor 1 + planetary gear reducer 2 can provide stepless speed regulation and precise torque control, avoiding the instability of the clamping force caused by the oil pressure fluctuation in the traditional hydraulic system; through the right-angle transmission of the driving bevel gear 5 and the driven bevel gear 19, the lateral space occupation is reduced; the structural design supported by the tapered roller bearing 4 can enhance the axial bearing capacity, reduce the transmission vibration, and improve the system rigidity.

[0045] In this embodiment, the ball nut 18 is installed inside the back clamp cylinder block 12 through the support of a thrust tapered roller bearing 13. There is a shoulder on the inner wall of the back clamp cylinder block 12, and there is one thrust tapered roller bearing 13 on each side of the shoulder. A driven lock nut 14 is installed at the rear end of the ball nut 18, and the two thrust tapered roller bearings 13 are supported between the driven lock nut 14 and the driven bevel gear 19.

[0046] It should be noted that the double thrust tapered roller bearings 13 are symmetrically arranged and can bear positive and negative loads simultaneously, avoiding the axial movement of the ball nut 18 under high-pressure working conditions, so as to meet the working condition requirements of the impact load scenario with frequent reversals during the drilling process.

[0047] In this embodiment, a back plate flange 17 is detachably installed at the rear end of the back clamp cylinder block 12. There is a limit groove on the inner side of the back plate flange 17. A plug plate 16 is detachably installed at the rear end of the ball screw 15, and the plug plate 16 cooperates with the limit groove. The inner side of the rear section of the ball nut 18 is a limit channel for the plug plate 16 to slide back and forth. At least two guiding keys 22 are symmetrically arranged on the outer diameter of the push rod 7, and a sealing seat 6 is provided at the front end of the back clamp cylinder block 12. A guiding key groove matching with the guiding keys 22 of the push rod 7 is provided on the sealing seat 6.

[0048] It should be noted that the setting of the backplane flange 17 and the blanking plate 16 prevents the drilling mud from invading the inside of the ball screw 15, ensuring the transmission accuracy; the design of the seal seat 6 and the guiding keyway structure thereon further ensures the stability of the linear motion of the push rod 7, reduces the wear of the screw caused by eccentric load, and further prevents dust and leakage in combination with the seal ring groove design.

[0049] In this embodiment, a seal ring groove is provided at the front end of the seal seat 6, and a seal support assembly 9 is installed in the seal ring groove. The seal support assembly 9 is used to seal the gap between the push rod 7 and the seal seat 6 and support the push rod 7.

[0050] It should be noted that the design of the seal ring groove and the seal support assembly 9 realizes a multi-layer sealing structure, which can not only isolate external pollutants but also provide a radial support force, avoiding the frictional loss caused by the self-weight sag of the push rod 7 and meeting the requirements of the drilling environment with high dust and high humidity.

[0051] In this embodiment, the back-up tong cylinder body 12 is connected to the lifting torque arm 10, and a rectangular flat key 11 is provided between the back-up tong cylinder body 12 and the lifting torque arm 10.

[0052] It should be noted that the rigid connection between the back-up tong cylinder body 12 and the lifting torque arm 10 is realized through the rectangular flat key 11, enhancing the torque transmission efficiency and preventing the connection from loosening due to vibration during operation, meeting the strict requirements of the top drive system for stability.

[0053] The specific implementation principle of the present invention is as follows: The electric actuated back clamp is connected to the top drive through the lifting torque arm 10, and cooperates with the top drive to complete the up and down movement. The lifting torque arm 10 is connected to the back clamp cylinder block 12 through a rectangular flat key 11 to bear the reaction force during the operation of the back clamp. The servo motor 1 serves as the power source of the system, providing the rotational speed and torque for the entire system mechanism, and is connected to the planetary gear reducer 2. The planetary gear reducer 2 is connected to the back clamp cylinder block 12. The planetary reducer is mainly used to reduce the transmission speed and increase the transmission torque. A pair of gear transmission pairs are arranged inside the back clamp cylinder block 12, and the main structure is a bevel gear. The driving bevel gear 5 is connected to the output shaft of the planetary gear reducer 2. A tapered roller bearing 4 is arranged outside the driving bevel gear 5, and the tapered roller bearing 4 is fixed on the flange seat 20. A driving locking nut 3 is arranged at one end of the driving bevel gear 5 to prevent the axial movement of the driving bevel gear 5. The driving bevel gear 5 meshes with the driven bevel gear 19, and the driven bevel gear 19 is connected to the ball screw pair. The driven bevel gear 19 and the ball nut 18 are integrally designed. A thrust tapered roller bearing 13 is arranged outside the ball nut 18, and the thrust tapered roller bearing 13 is fixed on the back clamp cylinder block 12. A driven locking nut 14 is arranged at one end of the ball nut 18 to prevent the axial movement of the ball nut 18. The ball screw 15 is connected to the push rod 7, and a plug plate 16 is connected to the other end of the ball screw 15 as the mechanical limit of the ball screw 15. The other end of the push rod 7 is connected to the back back clamp assembly 8. Two guide keys 22 are arranged on the outer diameter of the push rod 7. A sealing seat 6 is arranged at one end of the back clamp cylinder block 12. A sealing ring groove is arranged on the sealing seat 6 to install the sealing support assembly 9. The sealing seat 6 is also provided with a guide key groove, which cooperates with the guide key 22 of the push rod 7 to prevent the push rod 7 from rotating when moving axially. A back plate flange 17 is arranged at one end of the back clamp cylinder block 12 to seal the inside of the back clamp cylinder block 12. The front back clamp assembly 21 is connected to the back clamp cylinder block 12 through a pin 23.

[0054] The working principle of the present invention: The control system controls the servo motor 1 to transfer the rotational speed and torque to the driving bevel gear 5 through the process of decelerating and increasing torque by the planetary gear reducer 2. The driving bevel gear 5 transfers the rotational speed and torque to the driven bevel gear 19. The driven bevel gear 19 drives the ball nut 18 to rotate. Through the conversion of the ball screw pair, the torque is converted into the thrust of the ball screw 15, thereby driving the ball screw 15 and the push rod 7 to move axially. The back back clamp assembly 8 moves back and forth under the drive of the push rod 7, thereby realizing the clamping and loosening functions of the back back clamp assembly 8 on the drill pipe and realizing the working conditions of the drilling operation. During the drilling operation, the front back clamp assembly 21 is hinged to the back clamp cylinder block 12 through a pin 23 and is in a closed state.

[0055] The above are only the preferred embodiments of the present invention, and do not impose any limitations on the present invention. Any simple modifications, changes, and equivalent structural changes made to the above embodiments according to the technical essence of the present invention still fall within the protection scope of the technical solution of the present invention.

Claims

1. An electric actuated back-up tong for a top drive drilling device, characterized in that, It includes a driving unit, a pushing unit, a rear back-up clamp assembly, a front back-up clamp assembly and a back-up clamp cylinder block; The driving unit and the pushing unit are in transmission connection, and both the driving unit and the pushing unit are installed on the back-up clamp cylinder block; One end of the front back-up clamp assembly is hinged to the back-up clamp cylinder block, and the other end is detachably connected to the back-up clamp cylinder block; The rear back-up clamp assembly is connected to the pushing end of the pushing unit; The pushing unit is used to push the rear back-up clamp assembly to move towards the front back-up clamp assembly.

2. The electric actuated back-up tong for a top drive drilling device according to claim 1, wherein The pushing unit includes a ball screw and a ball nut used in cooperation with the ball screw, and the ball nut is in transmission connection with the driving unit; The ball nut is supported inside the back-up clamp cylinder block; the front end of the ball screw is detachably connected to a push rod, and the front end of the push rod is connected to the rear back-up clamp assembly.

3. The electric actuated back-up tong for a top drive drilling device according to claim 2, wherein The driving unit includes a servo motor and a planetary gear reducer, the servo motor and the planetary gear reducer are in transmission connection, and an active bevel gear is installed on the front output shaft of the planetary gear reducer; The front end of the ball nut has a driven bevel gear, and the active bevel gear meshes with the driven bevel gear.

4. The electro-actuated back-up tong for a top drive drilling device according to claim 3, wherein, The servo motor is installed above the planetary gear reducer, and the planetary gear reducer is installed on the back-up clamp cylinder block through a flange seat.

5. An electric actuated back-up tong for a top drive drilling device according to claim 3 or 4, characterized in that, The upper part of the active bevel gear is a tubular structure, the tubular structure is sleeved on the front output shaft of the planetary gear reducer, and the tubular structure is fixed by an active locking nut.

6. The electro - actuated back - up tong for a top - drive drilling device according to claim 2, characterized in that, The ball nut is supported and installed inside the back-up clamp cylinder block through a thrust tapered roller bearing.

7. An electric actuated back-up tong for a top drive drilling device according to claim 6, characterized in that, There is a shoulder on the inner wall of the back-up clamp cylinder block, there is one thrust tapered roller bearing on each side of the shoulder, a driven locking nut is installed at the rear end of the ball nut, and the two thrust tapered roller bearings support between the driven locking nut and the driven bevel gear.

8. The electric actuated back-up tong for a top drive drilling device according to claim 2, wherein, A back plate flange is detachably installed at the rear end of the back-up clamp cylinder block, a limiting groove is provided on the inner side of the back plate flange, a plug plate is detachably installed at the rear end of the ball screw, and the plug plate is matched with the limiting groove.

9. The electric actuated back-up tong for a top drive drilling device according to claim 8, wherein, The inner side of the rear section of the ball nut is a limiting channel for the plug plate to slide back and forth.

10. The electric actuated back-up tong for a top drive drilling device according to claim 2, characterized in that, At least two guiding keys are symmetrically arranged on the outer diameter of the push rod, a sealing seat is provided at the front end of the back-up clamp cylinder block, and guiding key grooves matched with the guiding keys of the push rod are provided on the sealing seat.

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