Tandem torque-increasing screw drill
By using a series-connected torque-enhancing screw drill design, combining a dual-motor assembly and a universal joint assembly, the problem of power attenuation in deep wells caused by traditional screw drills is solved, achieving high torque and long service life in deep well drilling and reducing drilling costs.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-31
- Publication Date
- 2026-04-03
AI Technical Summary
In deep well drilling, traditional screw drills suffer from motor wear, which leads to a decrease in sealing pressure and volumetric efficiency, as well as power loss. This makes them unable to meet the demands of long-term high-torque drilling. Existing torque-enhancing technologies lack stability and are difficult to achieve reliable operation over extended periods.
The drill bit adopts a series torque-increasing screw design, including a dual-motor assembly and a universal joint assembly. The torque is superimposed through the connection of the hemispherical shaft. It is equipped with a thrust bearing assembly and a disc spring assembly for shock absorption, and a composite inner seal ring to ensure sealing, so as to achieve complementary power output of the dual motors.
It significantly improves the rock-breaking ability of deep wells, extends the high-torque working time to 300-500 hours, increases the life of drill bits, enhances the impact resistance and torque transmission efficiency, and reduces drilling costs.
Smart Images
Figure CN224079063U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of screw drilling technology, specifically relating to a series torque-increasing screw drilling tool. Background Technology
[0002] As domestic oil and gas exploration continues to expand into deep and ultra-deep wells, higher demands are being placed on the output torque and service life of screw drills. After more than 200 hours of use, the core component of traditional screw drills, the motor, experiences wear, leading to a decrease in sealing pressure and volumetric efficiency, and a gradual reduction in power, making it unable to meet the demands of prolonged high-torque drilling. Although other components such as the drive shaft assembly and universal bearing assembly can still be used for 300-500 hours, the limited lifespan of the motor restricts the overall efficiency of the machine, forcing drilling operations to terminate prematurely and significantly increasing drilling costs.
[0003] Currently, although domestic screw drill manufacturers have begun research and development on motor torque enhancement technology, existing solutions generally suffer from insufficient stability and rapid decay of torque enhancement effects, making it difficult to achieve reliable operation over long periods. The contradiction between the urgent need for high-torque, long-life drill tools in deep well drilling and the current technological bottlenecks is becoming increasingly prominent, necessitating an innovative screw drill tool that can compensate for motor power decay and extend the high-torque working time. Utility Model Content
[0004] The purpose of this invention is to provide a series-connected torque-increasing screw drill bit to solve the problems existing in the background art.
[0005] To achieve the above objectives, this utility model provides the following technical solution: a series torque-increasing screw drill bit, comprising: a first motor assembly including a first stator and a first rotor; a second motor assembly including a second stator and a second rotor; a first universal joint assembly including a first universal joint housing and a first auger; a second universal joint assembly including a second universal joint housing and a second auger; a vibration-damping transmission shaft assembly including a transmission shaft, a thrust bearing assembly, and a disc spring assembly; the first motor assembly and the second motor assembly are connected in series via a hemispherical shaft, the two ends of which are fixed to the first rotor and the second rotor respectively; the first universal joint housing is connected to the first stator, and the second universal joint housing is connected to the second stator; the thrust bearing assembly is disposed within the transmission shaft, and the disc spring assembly is located at the axial top of the thrust bearing assembly. The dual-motor independent drive structure allows the other motor to compensate for power attenuation even after the first motor wears out, extending the high-torque working time to 300-500 hours, breaking through the lifespan limitations of traditional single-motor drill bits.
[0006] Preferably, the first rotor and the second rotor transmit torque through a ball joint, and the two ends of the ball joint are respectively connected to the first and second movable hinges through a first locking sleeve and a second locking sleeve; the ball joint is provided with a pressure-bearing ball, which contacts and engages with the hemispherical shaft.
[0007] Preferably, the transmission shaft is provided with an upper TC moving sleeve, an upper TC stationary sleeve, a disc spring assembly, a thrust bearing assembly, a pressure ring, a lower TC stationary sleeve, and a lower TC moving sleeve arranged sequentially along the axial direction; the upper TC stationary sleeve is fixedly connected to the transmission housing, and the transmission housing is connected to the second universal joint housing.
[0008] Preferably, the first and second movable screws have the same structure, both including a ball seat and a composite inner sealing ring; the ball seat is fixed inside the movable screw, and the composite inner sealing ring is disposed in the sealing groove of the movable screw.
[0009] Preferably, the top end of the second stator is directly connected to the first universal joint housing, and the bottom end of the second stator is connected to the second universal joint housing; a substitute connector is connected to the top end of the first stator, and a drill bit is connected to the end of the drive shaft.
[0010] Preferably, the first motor assembly and the second motor assembly are a dual-stage independent drive structure, and the rotation axes of the first rotor and the second rotor are collinear; the first universal joint housing is provided with a flexible groove structure, and the flexible groove structure is uniformly distributed along the circumference.
[0011] The beneficial effects of this utility model are as follows: This device achieves torque superposition output through the series design of dual motor assemblies, significantly improving the rock-breaking capability of deep wells. When the power attenuation is caused by wear of a single motor, the two motors can compensate for each other, extending the high-torque working time to 300-500 hours, breaking through the life limit of traditional single-motor drill bits. The thrust bearing assembly adopts a surface contact structure and is equipped with a disc spring damping mechanism, which greatly improves the drilling pressure bearing capacity and impact resistance. The flexible groove design of the upper universal joint housing effectively reduces stress concentration and enhances the fatigue life of the whole machine. The multi-stage sealing and transmission structure in the drive shaft optimizes the torque transmission efficiency and stability, and the composite inner sealing ring ensures the reliability of dynamic sealing. The overall structure is compact and adaptable to conventional drill strings, combining high drilling efficiency with convenient field application, achieving the comprehensive goals of speeding up, reducing costs, and increasing efficiency in deep well drilling. Attached Figure Description
[0012] Figure 1 This is a schematic diagram of the structure of this utility model. Detailed Implementation
[0013] The specific embodiments of this utility model are described in detail below with reference to the accompanying drawings and preferred embodiments.
[0014] like Figure 1As shown, a series-connected torque-increasing screw drill bit includes a first motor assembly, a second motor assembly, a first universal joint assembly, a second universal joint assembly, and a vibration-damping drive shaft assembly. The first motor assembly consists of a first stator 2 and a first rotor 3; the second motor assembly consists of a second stator 12 and a second rotor 13; the first motor assembly and the second motor assembly are connected in series via a hemispherical shaft 11, with both ends of the hemispherical shaft 11 fixed to the first rotor 3 and the second rotor 13, respectively.
[0015] The first universal joint assembly includes a first universal joint housing 4 and a first hinge 5. The first universal joint housing 4 is connected to the first stator 2. The first hinge 5 is fixed to one end of the ball joint 17 via a first locking sleeve 10. The second universal joint assembly includes a second universal joint housing 14 and a second hinge 15. The second universal joint housing 14 is connected to the second stator 12. The second hinge 15 is fixed to the other end of the ball joint 17 via a second locking sleeve 18. The ball joint 17 is provided with a pressure ball 16, which contacts and engages with the hemispherical shaft 11 to transmit torque and bear axial load.
[0016] The drive shaft 20 is provided with the following components arranged axially: upper TC moving sleeve 21, upper TC stationary sleeve 23, disc spring assembly 24, thrust bearing assembly 25, pressure ring 27, lower TC stationary sleeve 28, and lower TC moving sleeve 29. The upper TC stationary sleeve 23 is fixedly connected to the drive housing 26, and the drive housing 26 is connected to the second universal joint housing 14. The thrust bearing assembly 25 is located in the middle of the drive shaft 20. Its upper end is buffered by the disc spring assembly 24 to buffer the impact load, and its lower end is connected by the pressure ring 27 to transmit drilling pressure.
[0017] The first movable auger 5 and the second movable auger 15 have the same structure, both including a ball seat 6 and a composite inner sealing ring 8. The ball seat 6 is fixed inside the movable auger, and the composite inner sealing ring 8 is installed in the sealing groove of the movable auger. The top end of the second stator 12 is directly connected to the first universal joint housing 4, and the bottom end is connected to the second universal joint housing 14; the top end of the first stator 2 is connected to the substitute connector 1, and the end of the drive shaft 20 is connected to the drill bit.
[0018] The first motor and the second motor have a dual-stage independent drive structure, and the rotation axes of the first rotor 3 and the second rotor 13 are collinear. The first universal joint housing 4 is provided with a circumferentially uniformly distributed flexible groove structure.
[0019] Drilling fluid enters the drill string through the substitute connector 1, flowing sequentially through the first stator 2 and the first rotor 3, and the second stator 12 and the second rotor 13, creating a pressure difference at both ends of the dual motors, driving the first rotor 3 and the second rotor 13 to rotate synchronously. The torque of the first rotor 3 and the second rotor 13 is transmitted to the ball connecting rod 17 through the hemispherical shaft 11. The pressure-bearing ball 16 converts the torque into axial thrust and transmits it to the first auger 5 and the second auger 15, and finally to the drive shaft 20 through the universal joint assembly.
[0020] The disc spring assembly 24 inside the drive shaft 20 buffers the impact of drilling pressure, the thrust bearing assembly 25 bears the axial load, and the multi-stage TC dynamic / static sleeve and composite inner seal ring 8 ensure sealing performance and prevent drilling fluid leakage.
[0021] The drive shaft 20 transmits the combined torque from the two motors to the drill bit, enabling high-torque rock-breaking drilling in deep wells. When the power of a single motor decreases due to wear, the other motor can still drive independently, continuously providing stable torque.
[0022] It should be noted that, for those skilled in the art, several improvements and modifications can be made without departing from the principle of this utility model, and these improvements and modifications should also be considered within the scope of protection of this utility model.
Claims
1. A series torque multiplier screw drill, characterized by, The application relates to a double-motor transmission shaft assembly. The first motor assembly comprises a first stator (2) and a first rotor (3); The second motor assembly comprises a second stator (12) and a second rotor (13); The first universal shaft assembly comprises a first universal shaft housing (4) and a first live swivel (5); The second universal shaft assembly comprises a second universal shaft housing (14) and a second live swivel (15); The damping transmission shaft assembly comprises a transmission shaft (20), a thrust bearing group (25) and a disc spring group (24); The first motor assembly and the second motor assembly are connected in series through a hemispherical shaft (11), the two ends of the hemispherical shaft (11) are fixed with the first rotor (3) and the second rotor (13) respectively, the first universal shaft housing (4) is connected with the first stator (2), the second universal shaft housing (14) is connected with the second stator (12), the thrust bearing group (25) is arranged in the transmission shaft (20), and the disc spring group (24) is located at the axial top end of the thrust bearing group (25).
2. The series torsional screw drill tool of claim 1, wherein: The first rotor (3) and the second rotor (13) transmit torque through a ball connecting rod (17), the two ends of the ball connecting rod (17) are connected with the first live swivel (5) and the second live swivel (15) through a first locking sleeve (10) and a second locking sleeve (18) respectively, a pressure-bearing ball (16) is arranged in the ball connecting rod (17), and the pressure-bearing ball (16) is in contact with the hemispherical shaft (11).
3. The series torque multiplier screw drill tool of claim 1, wherein: An upper TC dynamic sleeve (21), an upper TC static sleeve (23), the disc spring group (24), the thrust bearing group (25), a pressure-bearing ring (27), a lower TC static sleeve (28) and a lower TC dynamic sleeve (29) are sequentially arranged in the transmission shaft (20) in the axial direction, the upper TC static sleeve (23) is fixedly connected with a transmission housing (26), and the transmission housing (26) is connected with the second universal shaft housing (14).
4. The series torque multiplier screw drill tool of claim 1, wherein: The first live swivel (5) and the second live swivel (15) are the same in structure and comprise a ball seat (6) and a composite inner sealing ring (8), the ball seat (6) is fixed in the live swivel, and the composite inner sealing ring (8) is arranged in a sealing groove of the live swivel.
5. The series torque multiplier screw drill tool of claim 1, wherein: The top end of the second stator (12) is directly connected with the first universal shaft housing (4), the bottom end of the second stator (12) is connected with the second universal shaft housing (14), the top end of the first stator (2) is connected with a substitute joint (1), and the end of the transmission shaft (20) is connected with a drill bit.
6. The series torque multiplier screw drill tool of claim 1, wherein: The first motor assembly and the second motor assembly are double-stage independent driving structures, the rotation axes of the first rotor (3) and the second rotor (13) are collinear, and the first universal shaft housing (4) is provided with a flexible groove structure which is uniformly distributed in the circumferential direction.