Composite intelligent vibration absorber based on centrifugal pendulum

Abstract

The invention provides a tool applied to the field of petroleum drilling, and particularly relates to a combined type intelligent vibration absorber based on a centrifugal pendulum. Comprising a sealing joint, a side cover plate, a battery, a power management module, a fixing screw, a main control unit, a vibration sensing unit, an embedded ring shell, a vibration absorption bracket, an axial long spring, a swinging block, an axial short spring, a pushing block, an insulating coil, a sliding joint, a vibration transmission shaft and magnetorheological fluid. The advantages of a spring, a centrifugal pendulum and a magnetorheological fluid damper are integrated, high-frequency and low-frequency random vibration absorption, axial vibration absorption of the spring and the magnetorheological fluid damper and circumferential vibration absorption of the centrifugal pendulum and the magnetorheological fluid damper are completed in a matched mode, an intelligent magnetorheological fluid damping automatic adjusting system is matched, and effective control over full-frequency-band vibration of a drill column is achieved.

Description

Technical Field

[0001] This invention is applicable to the field of oil drilling, and specifically relates to a composite intelligent vibration absorber based on a centrifugal pendulum. Background Technology

[0002] In modern oil drilling engineering, drill string vibration has always been a significant factor affecting drilling efficiency, drill bit life, and the reliability of downhole tools. Drill string vibration is generally classified into low-frequency and high-frequency bands. These vibrations not only lead to accelerated drill bit wear and reduced drilling speed, but can also cause fatigue damage to downhole tools and even trigger downhole accidents.

[0003] Traditional rubber vibration absorbers dissipate energy through the shear deformation of rubber, making them suitable for controlling torsional and axial vibrations in the low-frequency range. However, their energy dissipation is limited in the high-frequency range, and rubber materials are prone to aging and performance instability under high-temperature and high-pressure downhole environments. Magnetorheological fluid vibration absorbers are suitable for broadband vibration control, but traditional narrow-slit valve structures may experience a surge in dynamic stiffness in the high-frequency range, leading to direct impact penetration. Therefore, inventing a composite vibration absorption scheme that can effectively control both high- and low-frequency random vibrations of the drill string is of great significance. Summary of the Invention

[0004] The purpose of this invention is to propose a composite intelligent vibration absorber based on a centrifugal pendulum. By integrating the advantages of springs, centrifugal pendulums, and magnetorheological fluid dampers, it can effectively absorb high and low frequency random vibrations. Springs and magnetorheological fluid dampers absorb axial vibrations, while centrifugal pendulums and magnetorheological fluid dampers absorb circumferential vibrations. Combined with an intelligent system for autonomous adjustment of magnetorheological fluid damping, it can achieve effective control of full-frequency vibration of the drill string.

[0005] To achieve the above-mentioned objectives, the technical solution adopted by the present invention is as follows: the composite intelligent vibration absorber based on centrifugal pendulum is installed on the upper part of the drill bit, which can significantly reduce the vibration generated by the drill string during drilling.

[0006] The centrifugal pendulum-based composite intelligent vibration absorber includes a sealing joint, a side cover plate, a battery, a power management module, fixing screws, a main control unit, a vibration sensing unit, a ring housing, a vibration-absorbing bracket, an axial long spring, a swing block, an axial short spring, a push block, an insulating coil, a sliding joint, a transmission shaft, and magnetorheological fluid. The sealing joint is threadedly connected to the ring housing. The battery, power management module, main control unit, and vibration sensing unit are fixed in the annular space between the sealing joint and the side cover plate. The lower part of the vibration-absorbing bracket is threadedly connected to the ring housing, and the upper part of the vibration-absorbing bracket is sealed to the sealing joint and the ring housing. The upper part of the swing block contacts the axial long spring, and the lower part of the swing block contacts the axial short spring. Both are installed together in the fluid tank of the vibration-absorbing bracket. The two through holes of the swing block are installed with a gap to the transmission shaft, forming a suspended swing structure. The swing block uses the centrifugal force generated by the rotation of the vibration absorber as a restoring force, passively matching the excitation frequency to generate vibration opposite to the phase of the circumferential vibration, thus achieving the vibration absorption effect. The insulated coil is pre-insulated and embedded in the housing. When energized, the insulated coil generates a magnetic field, which can be adjusted by changing the coil current. The push block is fixed on the transmission shaft and moves axially with it. The sliding joint transmits torque to the vibration-absorbing bracket through a spline. The lower part connects to the drill bit. The lower part of the transmission shaft is fixedly connected to the sliding joint, and the lower part of the transmission shaft and the lower part of the vibration-absorbing bracket are dynamically sealed. The upper part of the transmission shaft floats through the through holes of the vibration-absorbing bracket and the swing block. Before finally installing the sealing joint, the liquid tank of the vibration-absorbing bracket is filled with magnetorheological fluid. When the magnetic field changes, the magnetorheological fluid changes its damping characteristics. When the installation is completed, the magnetorheological fluid formed between the vibration-absorbing bracket and the housing is completely sealed. The magnetorheological fluid generates adjustable damping in the axial and circumferential directions. When drilling generates vibration, the axial vibration is absorbed by the long axial spring and the short axial spring through the transmission shaft. The damping effect generated by the magnetorheological fluid consumes the vibration energy of the spring, while the circumferential vibration is absorbed by the centrifugal swing of the swing block.

[0007] As a further technical solution of the present invention, the vibration sensing unit has a built-in accelerometer that detects and feeds back vibration signals to the main control unit in real time. The power management module can adjust the current of the insulating coil in real time, thereby changing the magnetic field size and adjusting the damping generated by the magnetorheological fluid. This allows the main control unit to autonomously adjust the damping size to match high and low frequency vibrations. During low frequency vibrations, the main control unit controls the insulating coil to generate a smaller magnetic field. During high frequency vibrations, the main control unit controls the insulating coil to generate a stronger magnetic field, and the magnetorheological fluid generates high damping, so that the vibration absorber absorbs high frequency vibrations in both the axial and circumferential directions.

[0008] As a further technical solution of the present invention, the vibration absorption unit formed by the axial long spring, the swing block, the axial short spring, the push block and the vibration transmission shaft is evenly distributed in 4 groups circumferentially and in 2 groups axially.

[0009] Compared with the prior art, the beneficial effects of the present invention are: 1. By integrating the advantages of springs, centrifugal pendulums and magnetorheological fluid dampers, and with the help of a magnetorheological fluid self-adjustment intelligent system, full-frequency vibration control is achieved. The centrifugal pendulum part utilizes the self-tuning characteristics of its natural frequency and the drill string torsional frequency to automatically track vibration and efficiently dissipate energy. The main control unit adjusts the magnitude of the magnetorheological fluid damping in real time to achieve self-adjustment vibration absorption by the axial spring and the circumferential centrifugal pendulum.

[0010] 2. In the event of a power outage or system failure, the magnetorheological fluid damper can still provide a certain degree of damping, and the system can still absorb a certain amount of vibration, ensuring the system's safety in case of failure. Under normal operating conditions, the system effectively controls the high and low frequency vibration impacts of the drill string, reducing abnormal wear of the drill bit and fatigue damage to downhole tools, extending the service life of the drill bit, improving the overall efficiency of drilling operations, and reducing drilling costs. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the structure of the present invention; Figure 2 This is a cross-sectional view (AA) of the present invention; Figure 3 Isometric view of the vibration-absorbing bracket; Figure 4 Schematic diagram of the vibration-absorbing bracket assembly; Figure 5 This is a schematic diagram of the workflow of the present invention; In the diagram: 1-Sealed joint, 2-Side cover plate, 3-Battery, 4-Power management module, 5-Fixing screw, 6-Main control unit, 7-Vibration sensing unit, 8-Interlocking ring housing, 9-Vibration absorption bracket, 10-Axial long spring, 11-Swing block, 12-Axial short spring, 13-Push block, 14-Insulated coil, 15-Sliding joint, 16-Vibration transmission shaft, 17-Magnetorheological fluid. Detailed Implementation

[0012] The technical solutions of the embodiments of the present invention will be described in detail below with reference to the accompanying drawings. These embodiments are only a part of the present invention, and not all of it. Other embodiments obtained by those skilled in the art based on these embodiments without creative effort are also within the protection scope of the present invention.

[0013] Combination Figure 1 The composite intelligent vibration absorber based on a centrifugal pendulum is characterized in that: the composite intelligent vibration absorber based on a centrifugal pendulum is installed on the upper part of the drill bit, which can significantly reduce the vibration generated by the drill string during drilling.

[0014] Combination Figure 1 , Figure 2The centrifugal pendulum-based composite intelligent vibration absorber includes a sealing joint 1, a side cover plate 2, a battery 3, a power management module 4, fixing screws 5, a main control unit 6, a vibration sensing unit 7, a ring housing 8, a vibration absorption bracket 9, an axial long spring 10, a swing block 11, an axial short spring 12, a push block 13, an insulating coil 14, a sliding joint 15, a vibration transmission shaft 16, and a magnetorheological fluid 17. The sealing joint 1 is sealed to the ring housing 8 via threads. The battery 3, power management module 4, main control unit 6, and vibration sensing unit 7 are fixed to the sealing joint 1 and the side cover plate. In the annular space between plates 2, the lower part of the vibration-absorbing bracket 9 is sealed to the housing 8 via threads, and the upper part of the vibration-absorbing bracket 9 is sealed to the sealing joint 1 and the housing 8. The upper part of the swing block 11 contacts the axial long spring 10, and the lower part of the swing block 11 contacts the axial short spring 12. They are installed together in the liquid tank of the vibration-absorbing bracket 9. The two through holes of the swing block 11 are installed with a gap to the vibration transmission shaft 16, forming a suspended swing structure. The swing block 11 uses the centrifugal force generated by the rotation of the vibration absorber as a restoring force, passively matches the excitation frequency, and generates a vibration that is opposite in phase to the circumferential vibration, thereby achieving vibration absorption. To achieve the desired vibration effect, the insulated coil 14 is pre-insulated and embedded in the coil housing 8. When energized, the insulated coil 14 generates a magnetic field, which can be adjusted by changing the coil current. The push block 13 is fixed to the transmission shaft 16 and moves axially with it. The sliding joint 15 transmits torque to the vibration-absorbing bracket 9 via a spline. The lower part connects to the drill bit. The lower part of the transmission shaft 16 is fixedly connected to the sliding joint 15, and the lower part of the transmission shaft 16 is dynamically sealed to the lower part of the vibration-absorbing bracket 9. The upper part of the transmission shaft 16 floats through the through holes of the vibration-absorbing bracket 9 and the swing block 11. The tool is finally installed in a sealed manner. Before sealing the joint 1, the liquid tank of the vibration-absorbing bracket 9 is filled with magnetorheological fluid 17. When the magnetic field changes, the magnetorheological fluid 17 will change its own damping characteristics. When the installation is completed, the magnetorheological fluid 17 formed between the vibration-absorbing bracket 9 and the housing 8 is completely sealed. The magnetorheological fluid 17 generates adjustable damping in the axial and circumferential directions. When the drilling generates vibration, the axial vibration is absorbed by the axial long spring 10 and the axial short spring 12 through the vibration transmission shaft 16. The damping effect generated by the magnetorheological fluid 17 consumes the vibration energy of the spring, while the circumferential vibration is absorbed by the centrifugal swing of the swing block 11.

[0015] Combination Figure 1 The vibration sensing unit 7 has a built-in accelerometer that detects and feeds back vibration signals to the main control unit 6 in real time. The power management module 4 can adjust the current of the insulating coil 14 in real time, thereby changing the magnetic field size and adjusting the damping generated by the magnetorheological fluid 17. This allows the main control unit 6 to autonomously adjust the damping size to match high and low frequency vibrations. During low frequency vibrations, the main control unit 6 controls the insulating coil 14 to generate a smaller magnetic field. During high frequency vibrations, the main control unit 6 controls the insulating coil 14 to generate a stronger magnetic field, and the magnetorheological fluid 17 generates high damping, so that the vibration absorber absorbs high frequency vibrations in the axial and circumferential directions.

[0016] Combination Figure 4 The vibration absorption unit formed by the axial long spring 10, the swing block 11, the axial short spring 12, the push block 13 and the vibration transmission shaft 16 is evenly distributed in 4 groups circumferentially and 2 groups axially.

[0017] Combination Figure 1 , Figure 2 , Figure 3 , Figure 4 In this example, the working principle of the composite intelligent vibration absorber based on centrifugal pendulum is as follows: The composite intelligent vibration absorber based on centrifugal pendulum is installed on the upper part of the drill bit. When drilling generates vibration, the axial vibration is absorbed by the long axial spring 10 and the short axial spring 12. The magnetorheological fluid 17 acts as damping to consume the vibration energy of the spring. The circumferential vibration is absorbed by the centrifugal swing of the swing block 11. The swing block 11 uses the centrifugal force generated by the rotation of the vibration absorber as a restoring force, passively matching the excitation frequency, and generating vibration opposite to the phase of the circumferential vibration to achieve the vibration absorption effect. For vibrations of different frequencies, the main control unit 6 controls the insulating coil 14 to generate different magnetic fields, and the magnetorheological fluid 17 generates different damping so that the vibration absorber matches and absorbs vibrations of different frequencies.

[0018] Combination Figure 5 In one specific embodiment, when vibration occurs during drill string drilling, the vibration is transmitted to the vibration absorber through the sliding joint 15. The vibration sensing unit 7 detects the vibration and feeds it back to the main control unit 6. If the vibration frequency is low-frequency, the main control unit 6 controls the power management module 4 to output a small current to the insulating coil 14. The insulating coil 14 generates a magnetic field, and the magnetorheological fluid 17 generates a damping force under the influence of the magnetic field. If the vibration frequency is high-frequency, the main control unit 6 controls the power management module 4 to increase the current to the insulating coil 14, thereby strengthening the magnetic field generated by the insulating coil 14 and increasing the damping force of the magnetorheological fluid 17. The magnetorheological fluid 17 generates a large damping force to dissipate energy. The vibration absorption is decomposed into axial vibration and circumferential vibration. The axial vibration is transmitted to the long axial spring 10 and the short axial spring 12 through the push block 13. The springs absorb the axial vibration and dissipate it through the damping generated by the magnetorheological fluid. The circumferential vibration is transmitted to the swing block 11 through the vibration transmission shaft 16. The swing block 11 swings centrifugally and generates a vibration that is opposite in phase to the circumferential vibration to achieve vibration absorption. At the same time, the damping force of the magnetorheological fluid 17 dissipates the vibration energy. The axial and circumferential vibration absorption is completed. If vibration continues, the above process is repeated.

Claims

1. A composite intelligent vibration absorber based on a centrifugal pendulum, characterized in that: The composite intelligent vibration absorber based on centrifugal pendulum is installed on the upper part of the drill bit and can significantly reduce the vibration generated by the drill string during drilling. The centrifugal pendulum-based composite intelligent vibration absorber includes a sealing joint (1), a side cover plate (2), a battery (3), a power management module (4), fixing screws (5), a main control unit (6), a vibration sensing unit (7), a ring housing (8), a vibration absorption bracket (9), an axial long spring (10), a swing block (11), an axial short spring (12), a push block (13), an insulating coil (14), a sliding joint (15), a vibration transmission shaft (16), and a magnetorheological fluid (17). The sealing joint (1) is sealed to the ring housing (8) by threads. The battery (3), the power management module (4), the main control unit (6), and the vibration sensing unit (7) are connected together. Fixed in the annular space between the sealing joint (1) and the side cover plate (2), the lower part of the vibration-absorbing bracket (9) is sealed to the inner ring shell (8) by threads, and the upper part of the vibration-absorbing bracket (9) is sealed to the sealing joint (1) and the inner ring shell (8). The upper part of the swing block (11) contacts the axial long spring (10), and the lower part of the swing block (11) contacts the axial short spring (10). They are installed together in the liquid tank of the vibration-absorbing bracket (9). The two through holes of the swing block (11) are installed with the vibration transmission shaft (16) with a gap to form a suspended swing structure. The swing block (11) uses the centrifugal force generated by the rotation of the vibration absorber as the restoring force, passively matches the excitation frequency, and generates a phase with the circumferential vibration. The vibration is reversed to achieve the vibration absorption effect. The insulated coil (14) is insulated in advance and is embedded in the coil housing (8). The insulated coil (14) generates a magnetic field when energized, and the magnetic field can be adjusted by changing the coil current. The push block (13) is fixed on the transmission shaft (16) and moves axially with the transmission shaft (16). The sliding joint (15) transmits torque to the vibration absorption bracket (9) through the spline. The lower part is connected to the drill bit part. The lower part of the transmission shaft (16) is fixedly connected to the sliding joint (15), and the lower part of the transmission shaft (16) is dynamically sealed to the lower part of the vibration absorption bracket (9). The upper part of the transmission shaft (16) floats through the through hole of the vibration absorption bracket (9) and the swing block (11). The tool is in Before finally installing the sealing joint (1), fill the liquid tank of the vibration-absorbing bracket (9) with magnetorheological fluid (17). When the magnetic field changes, the magnetorheological fluid (17) will change its own damping characteristics. When the installation is completed, the magnetorheological fluid (17) formed between the vibration-absorbing bracket (9) and the ring housing (8) is completely sealed. The magnetorheological fluid (17) generates adjustable damping in the axial and circumferential directions. When the drilling generates vibration, the axial vibration is absorbed by the axial long spring (10) and the axial short spring (12) through the vibration transmission shaft (16). The damping effect generated by the magnetorheological fluid (17) consumes the vibration energy of the spring, while the circumferential vibration is absorbed by the centrifugal swing of the swing block (11).

2. The composite intelligent vibration absorber based on a centrifugal pendulum as described in claim 1 is characterized in that: The vibration sensing unit (7) has a built-in accelerometer that detects and feeds back vibration signals to the main control unit (6) in real time. The power management module (4) can adjust the current of the insulating coil (14) in real time, thereby changing the magnetic field size and adjusting the damping generated by the magnetorheological fluid (17). This allows the main control unit (6) to autonomously adjust the damping size to match high and low frequency vibrations. During low frequency vibrations, the main control unit (6) controls the insulating coil (14) to generate a smaller magnetic field. During high frequency vibrations, the main control unit (6) controls the insulating coil (14) to generate a stronger magnetic field, and the magnetorheological fluid (17) generates high damping, so that the vibration absorber absorbs high frequency vibrations in the axial and circumferential directions.

3. The composite intelligent vibration absorber based on a centrifugal pendulum as described in claim 1 is characterized in that: The vibration absorption units formed by the axial long spring (10), swing block (11), axial short spring (12), push block (13) and vibration transmission shaft (16) are evenly distributed in four groups circumferentially and two groups axially.

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