A kind of drilling rod damping device based on curved beam semi-active non-linear energy sink

Abstract

This invention relates to the field of drill pipe vibration reduction technology, specifically to a drill pipe vibration reduction device based on a semi-active nonlinear energy trap (NES) with a bending beam. The aim is to provide a drill pipe vibration reduction device based on a semi-active NES, suitable for deep hole machining and exhibiting good vibration reduction efficiency. This device includes a connecting base, a mounting plate, and NES components. Each NES component comprises a U-shaped sub-beam, an elastic main beam, a flexible hinge, and a PID controller. Each U-shaped sub-beam is fitted into an annular groove. One end of each elastic main beam is fixed to the middle of the intermediate beam of the U-shaped sub-beam, and the other end is fixed to the middle of the other side of the flexible frame in the width direction. Each U-shaped sub-beam is equipped with strain gauges. The input of the PID controller receives multiple strain gauges, and the output of the PID controller controls multiple piezoelectric ceramic stacks. The device described in this invention has a significant vibration suppression effect and is suitable for drilling operations.

Description

Technical Field

[0001] This invention relates to the field of drill pipe vibration reduction technology, specifically to a drill pipe vibration reduction device based on a semi-active nonlinear energy trap with a bending beam. Background Technology

[0002] In deep hole machining, the unique structure of the drill bit presents classic challenges: difficulty in vibration suppression, guidance, chip removal, cooling and lubrication, and low stiffness of the drill rod system. These problems have long plagued the deep hole machining industry. Furthermore, the machining of ultra-large aspect ratio deep holes is highly susceptible to external disturbances (such as drill rod whirling, tool chatter, cutting fluid self-excited oscillation, and forced vibration of the system), disrupting the stable balance of the drill bit's self-guiding section and exacerbating the nonlinear vibration of the system. Current vibration suppression methods for deep hole machining have narrow frequency bands and limited effectiveness. A simple and effective method is urgently needed to address the nonlinear vibration problem in the machining of ultra-large aspect ratio deep holes.

[0003] Traditional nonlinear energy sinks (NES), as a type of nonlinear passive vibration absorption device, have the advantage of being unaffected by external frequencies. They can control structural vibration through targeted energy transfer under broadband excitation and have good robustness. However, it is worth noting that although traditional NES can passively achieve vibration suppression over a wide frequency band, its vibration reduction efficiency is quite sensitive to the uncertainties of system parameters and the amplitude of external excitation. Semi-active NES, on the other hand, has better parameter tuning capabilities and ideal vibration reduction effects, and has become the development trend of NES vibration suppression. Summary of the Invention

[0004] The purpose of this invention is to provide a drill pipe vibration reduction device based on a semi-active NES that is suitable for deep hole machining and has good vibration reduction efficiency, namely a drill pipe vibration reduction device based on a bending beam semi-active nonlinear energy sink.

[0005] This invention is achieved using the following technical solution:

[0006] A drill pipe vibration reduction device based on a semi-active nonlinear energy trap with a bending beam includes a columnar connecting base, multiple mounting plates, and multiple sets of NES components. The connecting base has an annular groove at its axial center, with multiple sets of slots evenly distributed circumferentially on the annular groove. Each set of slots includes two slots symmetrically distributed on both sides of the groove wall. Both ends of each mounting plate are secured to the two slots in each set of slots. Each NES component includes a U-shaped sub-beam with an arc-shaped longitudinal section, an arc-shaped elastic main beam, a flexible hinge, and a PID controller. Each U-shaped sub-beam is secured within the annular groove, located between two adjacent mounting plates. The opening of each U-shaped sub-beam faces the corresponding mounting plate, and its two ends are respectively connected to the corresponding mounting plate. The left and right ends of the mounting plate are fixed. Each flexible hinge includes a rectangular flexible frame and a stack of piezoelectric ceramics installed in the flexible frame that can expand and contract along the circumferential direction of the connecting base. Each flexible frame is placed in the middle of the mounting plate and its left and right ends are respectively fixed to the two ends of the corresponding U-shaped sub-beam. The middle of one side of each flexible frame in the width direction is fixed to the corresponding mounting plate. One end of each elastic main beam is fixed to the middle of the middle beam of the corresponding U-shaped sub-beam, and the other end is fixed to the middle of the other side of the corresponding flexible frame in the width direction. Each U-shaped sub-beam is equipped with a strain gauge. The input of the PID controller receives multiple strain gauges, and the output of the PID controller controls multiple stacks of piezoelectric ceramics to drive the corresponding flexible frame to expand and contract.

[0007] Working Principle: The structure involved in this invention is a semi-active NES device. The U-shaped sub-beam serves as the added mass, and the elastic main beam acts as a damping element, providing nonlinear stiffness. In use, one end of the columnar connecting base is connected to the drill rod, and the other end is connected to the drill bit. When the drill rod vibrates, the strain gauge transmits the vibration signal to the PID controller. The PID controller outputs a certain voltage based on the vibration magnitude to control the expansion and contraction of the piezoelectric ceramic stack, causing displacement. This displacement is amplified by the flexible frame, which then pushes the elastic main beam to bend and deform, generating nonlinear stiffness. At this point, the elastic main beam forms the NES structure, and the drill rod vibration is transferred to the elastic main beam, which bends and deforms in the circumferential direction. This process repeats continuously. When the vibration energy gradually decreases to a certain critical value, the system can no longer be captured by the next new resonance state. At this point, the system no longer meets the conditions for resonance capture, so most of the vibration energy is consumed within the NES device and does not return to the main structure, thereby reducing the vibration generated by the drill rod during machining. This structure can use a PID controller to change the driving voltage of the piezoelectric ceramic stack, thereby generating different nonlinear stiffnesses in the elastic main beam and suppressing different degrees of vibration in the drill pipe.

[0008] Furthermore, each U-shaped sub-beam has a circumferential spacing between its non-open end and the adjacent mounting plate to facilitate the assembly and disassembly of NES components.

[0009] Furthermore, each U-shaped sub-beam has a connecting plate fixed at both ends of its opening for bolt connection with both ends of the mounting plate, facilitating the installation and fixing of the U-shaped sub-beam.

[0010] Furthermore, three end faces of the mounting plate are fixed with vertically arranged limiting plates, namely the left limiting plate, the right limiting plate, and the middle limiting plate. The three limiting plates are U-shaped as a whole, and their openings are arranged towards the direction close to the corresponding U-shaped sub-beam. The two connecting plates on each U-shaped sub-beam are respectively locked in the area formed by the left end of the corresponding left limiting plate and the left end of the corresponding middle limiting plate, and in the area formed by the right end of the corresponding right limiting plate and the right end of the corresponding middle limiting plate. The middle of one side of each flexible frame in the width direction is fixedly connected to the middle of the corresponding middle limiting plate, thus making the structure specific and fixed.

[0011] Furthermore, each of the four frame plates of the flexible frame has a connecting block fixed in the middle of its outer side, which facilitates fixing to the two ends of the corresponding intermediate limiting plate, elastic main beam, and U-shaped secondary beam respectively.

[0012] Furthermore, the two side panels of each flexible frame in the width direction are V-shaped to facilitate expansion and contraction.

[0013] Furthermore, each flexible frame is fitted with a protective shell by adhesive to waterproof the piezoelectric ceramic stack.

[0014] Furthermore, the outer arc surfaces of the U-shaped secondary beam and the elastic main beam are concentric with the outer circumference of the middle part of the connecting base and have the same radius, making the overall structure regular and occupying little space.

[0015] Furthermore, there are three mounting plates and three sets of NES components, making the structure more specific and standardized.

[0016] The beneficial effects of this invention are as follows: Based on a semi-active nonlinear energy trap, this invention can effectively dissipate the energy generated by drill pipe vibration, resulting in a significant vibration suppression effect. Furthermore, by changing the piezoelectric stack driving voltage, the nonlinear stiffness in the bending beam's nonlinear energy trap can be indirectly altered, thereby changing its vibration suppression capability in different frequency bands. This invention, with its reasonable design and simple, effective structure, provides a framework and method for active vibration reduction of drill pipes. Attached Figure Description

[0017] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, those skilled in the art can obtain other drawings based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0020] Figure 2 This is a schematic diagram of the connecting base structure;

[0021] Figure 3 A structural schematic diagram of the U-shaped secondary beam and the elastic main beam;

[0022] Figure 4 This is a structural diagram of the mounting plate, left limiting plate, right limiting plate, and middle limiting plate;

[0023] Figure 5 This is a schematic diagram of the flexible frame structure;

[0024] Figure 6 This is a schematic diagram of the assembly structure of a single NES component and mounting plate;

[0025] Figure 7 This is a schematic diagram of the assembly structure of three sets of NES components and three mounting plates;

[0026] Figure 8 Simulation of free vibration attenuation of drill pipe with NES component as described in this invention;

[0027] Figure 9 This is a schematic diagram showing the amplitude of a drill pipe with and without the NES component described in this invention.

[0028] In the diagram: 1-Connecting base, 2-Mounting plate, 3-Annular groove, 4-Card slot, 5-U-shaped secondary beam, 6-Elastic main beam, 7-Flexible frame, 8-Piezoelectric ceramic stack, 9-Circumferential spacing, 10-Connecting plate, 11-Left limiting plate, 12-Middle limiting plate, 13-Right limiting plate, 14-Connecting block, 15-Protective shell. Detailed Implementation

[0029] To better understand the above-mentioned objectives, features, and advantages of the present invention, the solutions of the present invention will be further described below. It should be noted that, unless otherwise specified, the embodiments of the present invention and the features thereof can be combined with each other.

[0030] In this description, it should be noted that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. It should also be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joint" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms according to the specific circumstances.

[0031] Many specific details are set forth in the following description in order to provide a full understanding of the invention, but the invention may also be practiced in other ways different from those described herein; obviously, the embodiments in the specification are only some embodiments of the invention, and not all embodiments.

[0032] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0033] like Figures 1 to 7 As shown, a drill pipe vibration reduction device based on a semi-active nonlinear energy sink with a bending beam includes a columnar connecting base 1, multiple mounting plates 2, and multiple sets of NES components. The connecting base 1 has an annular groove 3 at its axial center. Multiple sets of slots 4 are evenly distributed circumferentially on the annular groove 3. Each set of slots 4 includes two slots 4 symmetrically distributed on both sides of the annular groove 3. Both ends of each mounting plate 2 are secured to the two slots 4 in each set of slots 4. Each set of NES components includes a U-shaped sub-beam 5 with an arc-shaped longitudinal section, an arc-shaped elastic main beam 6, a flexible hinge, and a PID controller. Each U-shaped sub-beam 5 is secured within the annular groove 3. Each U-shaped sub-beam 5 is located between two adjacent mounting brackets. The opening of each U-shaped sub-beam 5 faces the corresponding mounting plate 2, and its two ends are respectively connected to... The left and right ends of the corresponding mounting plate 2 are fixed. Each flexible hinge includes a rectangular flexible frame 7 and a piezoelectric ceramic stack 8 installed in the flexible frame 7 and capable of telescoping along the circumferential direction of the connecting base 1. Each flexible frame 7 is placed in the middle of the mounting plate 2 and its left and right ends are respectively fixed to the two ends of the corresponding U-shaped sub-beam 5. The middle of one side of each flexible frame 7 in the width direction is fixed to the corresponding mounting plate. One end of each elastic main beam 6 is fixed to the middle of the middle beam of the corresponding U-shaped sub-beam 5, and the other end is fixed to the middle of the other side of the corresponding flexible frame 7 in the width direction. Each U-shaped sub-beam 5 is equipped with a strain gauge. The input of the PID controller receives multiple strain gauges, and the output of the PID controller controls multiple piezoelectric ceramic stacks 8 to drive the corresponding flexible frame 7 to telescop and deform.

[0034] Working Principle: The structure involved in this invention is a semi-active NES device. The U-shaped secondary beam 5 is an additional mass, and the elastic main beam 6 is a damping element that can provide nonlinear stiffness. In use, one end of the columnar connecting base 1 is connected to the drill rod, and the other end is connected to the drill bit. When the drill rod vibrates, the strain gauge transmits the vibration signal to the PID controller. The PID controller outputs a certain voltage according to the vibration magnitude to control the expansion and contraction of the piezoelectric ceramic stack 8, causing it to displace. This displacement is amplified by the flexible frame 7, which then pushes the elastic main beam 6 to bend and deform, generating nonlinear stiffness. At this time, the elastic main beam 6 forms an NES structure, and the vibration of the drill rod is transferred to the elastic main beam 6. The elastic main beam 6 bends and deforms in the circumferential direction. This process is continuously repeated. When the vibration energy gradually decreases to a certain critical value, the system can no longer be captured by the next new resonance state. At this time, the system no longer meets the conditions for resonance capture. Therefore, most of the vibration energy will be consumed in the NES device and will not return to the main structure, thereby reducing the vibration generated by the drill rod during machining. This structure can change the driving voltage of the piezoelectric ceramic stack 8 through a PID controller, so that the elastic main beam 6 produces different nonlinear stiffnesses, thereby suppressing the vibration of the drill pipe to different degrees.

[0035] In practice, a circumferential spacing 9 is provided between the non-open end of each U-shaped sub-beam 5 and the adjacent mounting plate 2 to facilitate the assembly and disassembly of NES components.

[0036] In practice, each U-shaped sub-beam 5 has a connecting plate 10 fixed at both ends of its opening for bolt connection with the two ends of the mounting plate 2, which facilitates the installation and fixing of the U-shaped sub-beam 5.

[0037] In specific implementation, three end faces of the mounting plate 2 are fixed with vertically arranged limiting plates, namely the left limiting plate 11, the right limiting plate 13, and the middle limiting plate 12. The three limiting plates are U-shaped as a whole, and their openings are arranged in the direction close to the corresponding U-shaped sub-beam 5. The two connecting plates 10 on each U-shaped sub-beam 5 are respectively locked in the area formed by the left end of the corresponding left limiting plate 11 and the left end of the corresponding middle limiting plate 12, and the area formed by the right limiting plate 13 and the right end of the corresponding middle limiting plate 12. The middle of one side of each flexible frame 7 in the width direction is fixedly connected to the middle of the corresponding middle limiting plate 12, thus making the structure specific and fixed.

[0038] In practice, each of the four outer side panels of each flexible frame 7 is fixed with a connecting block 14, which is convenient to be fixed to the two ends of the corresponding intermediate limiting plate 12, elastic main beam 6, and U-shaped secondary beam 5 respectively.

[0039] In practice, the two side panels of each flexible frame 7 in the width direction are V-shaped to facilitate expansion and contraction.

[0040] In practice, each flexible frame 7 is covered with a protective shell 15 for waterproofing the piezoelectric ceramic stack 8 by adhesive.

[0041] In practice, the outer arc surfaces of the U-shaped secondary beam 5 and the elastic main beam 6 are concentric with the outer circumference of the middle part of the connecting base 1 and have the same radius, making the overall structure regular and occupying little space.

[0042] In practice, there are three mounting plates 2 and three sets of NES components, making the structure specific and standardized.

[0043] To verify the vibration suppression performance of the device, a simulation of the free vibration attenuation of the drill pipe is performed, such as... Figure 8 As shown, the amplitude of the NES fluctuates. When the NES first experiences a high amplitude, target energy transfer occurs, consuming the drill pipe's vibration energy, and the drill pipe amplitude with the NES decreases. Subsequently, the NES amplitude decreases, and the drill pipe amplitude with the NES increases. This is because after the previous target energy transfer, the drill pipe system's energy escapes from the NES's damping frequency band, making the NES unable to capture the existing vibration mode for damping. At this point, after the PID controller controls the piezoelectric ceramic stack 8 and thus controls the stiffness of the elastic main beam 6, the NES experiences a high amplitude again, and target energy transfer occurs again, and so on until the variable stiffness capability is exceeded.

[0044] In addition, from Figure 9 It can be seen that the drill rod with NES has a significantly lower amplitude than the drill rod without NES, demonstrating a significant vibration suppression effect. This proves that the device described in this invention has a good vibration reduction effect, and its simple structure and small footprint make it suitable for deep hole machining.

[0045] The above description is merely a specific embodiment of the present invention, enabling those skilled in the art to understand or implement the present invention. Although detailed descriptions have been provided with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments, and they should all be covered within the protection scope of the claims.

Claims

1. A drill pipe vibration reduction device based on a semi-active nonlinear energy trap with a bending beam, characterized in that, The system includes a columnar connecting base (1), multiple mounting plates (2), and multiple sets of NES components. The connecting base (1) has an annular groove (3) in the axial center. Multiple sets of slots (4) are evenly distributed circumferentially on the annular groove (3). Each set of slots (4) includes two slots (4) and is symmetrically distributed on both sides of the groove wall of the annular groove (3). Both ends of each mounting plate (2) are fixed to the two slots (4) of each set of slots (4). Each set of NES components includes a U-shaped sub-beam (5) with a circular arc cross-section, a circular arc elastic main beam (6), a flexible hinge, and a PID controller. Each U-shaped sub-beam (5) is fixed in the annular groove (3). Each U-shaped sub-beam (5) is located between two adjacent mounting brackets. The opening of each U-shaped sub-beam (5) is arranged facing the corresponding mounting plate (2), and its two ends are respectively connected to the corresponding mounting plate (2). The left and right ends are fixed. Each flexible hinge includes a rectangular flexible frame (7) and a piezoelectric ceramic stack (8) installed in the flexible frame (7) and capable of stretching and contracting along the circumferential direction of the connecting base (1). Each flexible frame (7) is placed in the middle of the mounting plate (2) and its left and right ends are respectively fixed to the two ends of the corresponding U-shaped sub-beam (5). The middle of one side of the width direction of each flexible frame (7) is fixed to the corresponding mounting plate. One end of each elastic main beam (6) is fixed to the middle of the middle beam of the corresponding U-shaped sub-beam (5), and the other end is fixed to the middle of the other side of the width direction of the corresponding flexible frame (7). Each U-shaped sub-beam (5) is equipped with a strain gauge. The input end of the PID controller receives multiple strain gauges, and the output end of the PID controller controls multiple piezoelectric ceramic stacks (8) to drive the corresponding flexible frame (7) to stretch and contract.

2. The drill pipe vibration reduction device based on a semi-active nonlinear energy trap with a bending beam according to claim 1, characterized in that, Each U-shaped sub-beam (5) has a circumferential spacing (9) between its non-open end and the adjacent mounting plate (2).

3. The drill pipe vibration reduction device based on a semi-active nonlinear energy trap with a bending beam according to claim 2, characterized in that, Each U-shaped sub-beam (5) has a connecting plate (10) fixed at both ends of its opening for bolt connection with the two ends of the mounting plate (2).

4. The drill pipe vibration reduction device based on a semi-active nonlinear energy trap with a bending beam according to claim 3, characterized in that, The mounting plate (2) has three vertically arranged limiting plates fixed on its three end faces, namely the left limiting plate (11), the right limiting plate (13), and the middle limiting plate (12). The three limiting plates are U-shaped and their openings are arranged in the direction close to the corresponding U-shaped sub-beam (5). The two connecting plates (10) on each U-shaped sub-beam (5) are respectively locked in the area formed by the left end of the corresponding left limiting plate (11) and the left end of the corresponding middle limiting plate (12), and in the area formed by the right end of the corresponding right limiting plate (13) and the right end of the corresponding middle limiting plate (12). The middle part of one side of each flexible frame (7) in the width direction is fixedly connected to the middle part of the corresponding middle limiting plate (12).

5. A drill pipe vibration reduction device based on a semi-active nonlinear energy trap with a bending beam according to claim 4, characterized in that, Each flexible frame (7) has a connecting block (14) fixed at the middle of the outer side of the four frame plates.

6. The drill pipe vibration reduction device based on a semi-active nonlinear energy trap with a bending beam according to claim 5, characterized in that, The two side panels of each flexible frame (7) in the width direction are V-shaped.

7. A drill pipe vibration reduction device based on a semi-active nonlinear energy trap with a bending beam according to claim 6, characterized in that, Each flexible frame (7) is covered by a protective shell (15) for waterproof encapsulation of the piezoelectric ceramic stack (8) by adhesive.

8. A drill pipe vibration reduction device based on a semi-active nonlinear energy trap with a bending beam according to claim 7, characterized in that, The outer arc surfaces of the U-shaped secondary beam (5) and the elastic main beam (6) are concentric with and have the same radius as the outer circumference of the middle part of the connecting base (1).

9. A drill pipe vibration reduction device based on a semi-active nonlinear energy trap with a bending beam according to claim 8, characterized in that, There are three mounting plates (2) and three sets of NES components.

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