Multi-directional tunable dynamic vibration absorption device for pipelines and design method thereof

Abstract

The present invention discloses a multi-directional tunable dynamic vibration absorption device for a pipeline and a design method. The vibration absorption device includes a pair of semi-circular vibration absorption shells that can be symmetrically engaged with the outer wall of the pipeline. The vibration absorption shells include an inner circular arc plate, an outer circular arc plate and a plurality of ribs. The plurality of ribs are arranged between the inner circular arc plate and the outer circular arc plate along the radial direction of the vibration absorption shell. A vibration absorption chamber for installing a vibration absorption component is formed between two adjacent ribs. The vibration absorption component includes a mass block and an elastic member. The mass block can rotate along the circumference of the vibration absorption shell. The elastic member is arranged between the mass block and the ribs along the circumference of the vibration absorption shell. The vibration absorption method fixes the vibration absorption device on the pipeline for vibration absorption.

Description

Technical Field

[0001] The invention in this application belongs to the field of nuclear power plant pipeline vibration control, and is mainly used for low-frequency and medium-frequency vibration control of in-service pipelines, absorbing pipeline vibration energy, reducing pipeline vibration displacement amplitude, and preventing vibration fatigue fracture of pipelines. Specifically, it relates to a pipeline multi-directional tunable dynamic vibration absorption device and its design method. Background Art

[0002] Numerous pipelines in nuclear power plants experience low-frequency vibrations, with frequencies below 30Hz. This poses a serious safety hazard and can easily lead to vibration fatigue fractures in smaller, attached pipelines. Therefore, the dynamic vibration absorbers studied in this project are primarily designed to address low-frequency vibrations in large nuclear power plant pipelines, reducing the vibration amplitude and preventing vibration fatigue failure in smaller pipelines.

[0003] Dynamic vibration absorbers are composed of three fundamental elements: mass, stiffness, and damping. By vibrating in concert with the main system, they store and absorb the main system's vibration energy. Different dynamic vibration absorber parameters produce varying vibration absorption effects on the main system, and different main system parameters also require different optimal absorber parameters. Therefore, in the design, matching, and optimization of dynamic vibration absorbers, to achieve optimal vibration absorption, it is necessary to first design the dynamic vibration absorber parameters based on the main system's vibration response.

[0004] The 719th Research Institute of China Shipbuilding Industry Corporation has applied for an invention patent for a "Pipeline Dynamic Vibration Absorber" (patent number CN106122605A). The device features a dual-ring design: the inner ring is secured to the pipeline via clamp bolts, while the outer ring is bolted to the pipeline. A spring and a slider with a specific stiffness are positioned on the outer side of the bolts. The movement of the slider and spring eliminates pipeline vibration, achieving a one-way vibration reduction effect.

[0005] China University of Petroleum (Beijing) has applied for an invention patent for an "industrial pipeline dynamic vibration absorber" (patent publication number CN105570545A). The device consists of a steel plate support and an adjustable mass. When the pipeline vibrates, the absorber generates an inertial force that reacts to the pipeline, thereby suppressing the vibration and achieving a one-way vibration reduction effect.

[0006] Shanghai Jiao Tong University has applied for an invention patent for a "Variable Stiffness and Variable Damping Tunable Dynamic Vibration Absorber" (Patent Publication No. CN106090098B). The device consists of a fixed frame and a double-ended electromagnetic variable damping assembly. By adjusting the stiffness to change the absorber's natural frequency and adjusting the electromagnetic damping to achieve the optimal damping ratio, it achieves unidirectional vibration reduction.

[0007] Wuhan University of Technology has applied for an invention patent for "A Frequency-Adjustable Broadband Dynamic Vibration Absorber and Method Thereof" (Patent Publication No. CN106051015B). The device consists of a base, a screw, a vibration-absorbing unit, and a sliding metal plate. The unit includes a mass and an elastic rubber damping plate. The rubber damping plate absorbs vibration energy through its elasticity and damping properties. Adjusting the thickness and position of the rubber plate allows for broadband vibration control. However, its structure and installation method are not suitable for vibration reduction in pipeline structures.

[0008] Northwestern Polytechnical University has applied for an invention patent for a "permanent magnet eddy current energy-absorbing dynamic vibration absorber" (patent number: CN105156532A). The device consists of linear bearings, permanent magnets, coil springs, etc. It absorbs vibrations by generating a magnetic field, which can minimize the resonance peak of the controlled system.

[0009] Harbin Engineering University has applied for an invention patent for a "variable damping hybrid dynamic vibration absorber" (patent publication number CN104295651 B). The device consists of balls, grooves, permanent magnets, a base, etc., and can adjust the damping ratio to achieve the optimal design.

[0010] Xi'an Jiaotong University published a paper titled "Design and Parameterization of a New Adjustable Dynamic Vibration Absorber," which introduced a new type of adjustable dynamic vibration absorber consisting of a flexible coil spring and a magnetic negative stiffness spring. Based on the steady-state equations and criteria under simple harmonic excitation, the absorber structure was designed to effectively limit low-frequency vibrations.

[0011] In summary, current dynamic vibration absorber designs are based on two fundamental principles: 1) absorbing vibration energy through magnetic absorption, and 2) counteracting pipeline vibration by generating inertial force through springs, steel plates, and other devices. Magnetic dynamic vibration absorbers are relatively expensive and unsuitable for pipeline vibration reduction. Spring and steel plate dynamic vibration absorbers, however, are limited by spring stiffness, mass, and space constraints, making them less effective for large-scale pipelines with significant inherent mass. Summary of the Invention

[0012] In view of this, in order to overcome the defects of existing vibration absorption devices, the present invention provides a pipeline multi-directional tunable dynamic vibration absorption device, which has a good vibration absorption effect on large-scale pipelines in nuclear power plants, can significantly reduce the vibration displacement amplitude of the pipelines, and has the characteristics of compact structure, simple form and easy installation.

[0013] In order to achieve the above object, the present invention adopts the following technical solutions:

[0014] A multi-directional tunable dynamic vibration absorption device for a pipeline comprises two vibration absorption units arranged on the outer wall of the pipeline, each of the vibration absorption units comprises a vibration absorption shell in the shape of a semicircular ring, the vibration absorption shell comprises an inner circular arc plate, an outer circular arc plate and a plurality of ribs, the plurality of ribs are arranged between the inner circular arc plate and the outer circular arc plate along the radial direction of the vibration absorption shell, and a vibration absorption chamber for installing a vibration absorption assembly is formed between two adjacent ribs, the vibration absorption assembly comprises a mass block and an elastic member, the mass block is rotatably arranged on the inner circular arc plate, and the elastic member is arranged between the mass block and the ribs. The two vibration-absorbing shells are spliced ​​and stuck on the outer wall of the pipe. The inner arc plate is in direct contact with the outer wall of the pipe, transmitting the vibration energy of the pipe while reacting the inertia force of the vibration absorber to the pipe. The outer arc plate can protect the free movement of the mass block from external interference, and at the same time enhance the overall rigidity of the device of the present invention. The rib plate mainly connects the inner arc plate and the outer arc plate, and at the same time bears the reaction force generated during the compression and stretching of the elastic part; the mass block and the elastic part are the main vibration-absorbing components. During the vibration of the pipe, the reverse inertia force is generated to offset the vibration energy of the pipe, thereby reducing the amplitude of the vibration displacement of the pipe. The vibration-absorbing device is arranged symmetrically, which can achieve a bidirectional vibration reduction effect in the radial direction of the pipe.

[0015] In the above technical solution, preferably, the mass block includes a hinge plate and a mass block body, the hinge plate is rotatably arranged on the inner arc plate, and the mass block body is arranged at the free end of the hinge plate.

[0016] In the above technical solution, it is further preferred that the inner circular plate is provided with a hinge ring, the hinge plate is mounted on the inner circular plate via the hinge ring, and the mass body can rotate about the hinge ring. The hinge plate and the inner circular plate are connected by the hinge ring, and the hinge ring is integrally machined and welded to the surface of the inner circular plate. That is, the hinge plate and the mass body rotate as a whole about the hinge ring, and the mass body is welded to the free end of the hinge plate.

[0017] In the above technical solution, it is further preferred that the number of the hinge rings is two, and the two hinge rings are symmetrically arranged at both ends of the width direction of the outer wall surface of the inner circular plate. A hinge shaft is provided on both sides of the width direction of one end of the hinge plate near the inner circular plate, and is configured to extend into the hinge ring. The diameter of the hinge shaft is smaller than the inner diameter of the hinge ring. The surface roughness of the hinge shaft is Ra12.5.

[0018] In the above technical solution, it is further preferred that the circumferential distance between the axis of the hinged circular shaft and one of the two ribs is equal to the circumferential distance between the axis of the hinged circular shaft and the other of the two ribs. Within a vibration absorption chamber, the hinge ring is located halfway along the circumference of the inner arc plate. That is, in the initial state, the hinge plate and the mass body are located in the middle of the vibration absorption chamber, dividing the chamber into two equal parts.

[0019] In the above technical solution, it is further preferred that the elastic members are provided on both sides of the hinge plate. Each hinge plate and mass body corresponds to two elastic members, and the two ribs in one vibration absorbing chamber simultaneously bear the reaction force generated during the compression and extension of the elastic members.

[0020] In the above technical solution, and further preferably, the elastic member is a coil spring, one end of the coil spring acts on the hinge plate, and the other end of the coil spring acts on the rib plate. Both end surfaces of the coil spring are fixed to the hinge plate and the rib plate by welding.

[0021] In the above technical solution, it is further preferred that the stiffness of the two coil springs on both sides of the hinge plate is equal.

[0022] In the above technical solution, preferably, a gap is provided between the inner wall of the outer circular plate and the mass body. When the medium inside the pipeline is at high temperature, the hinged plate of the vibration absorber will undergo significant radial expansion due to the thermal expansion effect of the metal. The appropriate gap between the mass body and the outer circular plate ensures free movement of the mass.

[0023] In the above technical solution, it is further preferred that the number of ribs is three, with a quarter of a circumference separating two adjacent ribs. A vibration absorbing shell has three ribs, with a quarter of a circumference separating two adjacent ribs. That is, each vibration absorbing unit has two vibration absorbing chambers within a vibration absorbing shell. There are two hinged plates and two mass bodies. In the original state, the two hinged plates and the two mass bodies are also separated by a quarter of a circumference.

[0024] The present invention also provides a design method for a pipeline multi-directional tunable dynamic vibration absorbing device, comprising the following steps:

[0025] Taking the reduction of the vibration displacement amplitude of a pipeline in a certain direction as an example, the design parameter calculation process is as follows:

[0026] 1) First, according to the expected vibration reduction effect of the pipeline, the ratio of the mass block body to the pipeline weight is determined according to formulas (1) to (3), and then the mass M of the mass block body is determined; where X is the expected vibration displacement value, X st is the vibration displacement value of the pipeline, μ is the mass ratio, MS is the ratio of the pipe mass.

[0027] (X / X st )=0.827(μ+0.02) -0.62 (1)

[0028]

[0029]

[0030] 2) Determine the frequency ratios λ1 and λ2 of the mass block and spring assembly of the vibration absorber by using the empirical optimal demodulation formulas (4) to (7), and then determine the natural frequency; where λ1 and λ2 are the ratios of the natural frequencies f1 and f2 of the two symmetrical assemblies to the pipeline vibration frequency 1f0, where 1f0 is obtained through field testing.

[0031] λ1=0.403(μ+0.131) -0.437 (4)

[0032] λ2=-0.72μ+1.03 (5)

[0033] f1=λ1f0 (6)

[0034] f2=λ2f0 (7)

[0035] 3) Using formulas (8) and (9), calculate the spring stiffness K1 and K2, where K1 is the spring stiffness corresponding to one of the hinged plates / mass blocks, and K2 is the spring stiffness of the hinged plates / mass blocks at symmetrical positions. The two hinged plates are in the same plane.

[0036]

[0037]

[0038] Due to the adoption of the above technical solution, compared with the prior art, the advantages of the present invention are as follows: the multi-directional tunable dynamic vibration absorption device for pipelines of the present invention, the inner arc plate, the outer arc plate and the rib plate constitute a vibration absorption chamber, a vibration absorption assembly including a mass block and an elastic member is arranged in the vibration absorption chamber, the inner arc plate is in direct contact with the outer wall surface of the pipeline, transmits the vibration energy of the pipeline and reacts the inertia force of the vibration absorber to the pipeline, the outer arc plate protects the free movement of the mass block from external interference, and at the same time enhances the overall rigidity of the device of the present invention, the rib plate is used to connect the inner arc plate and the outer arc plate, and at the same time bears the reaction force generated during the compression and stretching process of the elastic member, during the vibration process of the pipeline, the mass block and the elastic member generate reverse inertia force to offset the vibration energy of the pipeline, thereby reducing the vibration displacement amplitude of the pipeline, and the vibration absorption device is symmetrically arranged, which can achieve a bidirectional vibration reduction effect in the radial direction of the pipeline, thereby having a good vibration absorption effect on large-scale pipelines in nuclear power plants and can significantly reduce the vibration displacement amplitude of the pipeline. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0040] Figure 1 Schematic diagram of the structure of the vibration absorbing shell in the multi-directional tunable dynamic vibration absorbing device for pipelines in a preferred embodiment of the present invention;

[0041] In the accompanying drawings: inner arc plate 100, outer arc plate 200, first rib plate 310, second rib plate 320, third rib plate 330, first coil spring 410, second coil spring 420, hinge plate 431, mass block body 432, hinge ring 500. DETAILED DESCRIPTION

[0042] In order to enable those skilled in the art to better understand the technical solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0043] Example: A multi-directional tunable dynamic vibration absorbing device for a pipeline comprises two vibration absorbing units arranged on the outer wall of the pipeline, each vibration absorbing unit comprises a semicircular vibration absorbing shell, and the two vibration absorbing shells can be clamped on the outer wall of the pipeline. The specific structure of the vibration absorbing shell is shown in FIG. Figure 1The vibration absorbing shell includes an inner arc plate 100, an outer arc plate 200, a first rib 310, a second rib 320, and a third rib 330. The first rib 310, the second rib 320, and the third rib 330 are radially disposed between the inner arc plate 100 and the outer arc plate 200. Four bolts are provided on each of the first rib 310 and the third rib 330 to integrate the two parts of the vibration absorbing shell and mount them on the outer wall of the pipe. A vibration absorbing chamber for mounting a vibration absorbing assembly is formed between the first rib 310 and the second rib 320, and between the second rib 320 and the third rib 330. That is, two vibration absorbing chambers are provided within the vibration absorbing shell, and the two chambers are of equal size. The first rib 310 and the second rib 320 are separated by a quarter of a circumference, and the second rib 320 and the third rib 330 are separated by a quarter of a circumference.

[0044] The vibration absorption assembly in each vibration absorption chamber includes a hinged plate, a mass block body and two coil springs. The vibration absorption assembly is described in detail below using the vibration absorption chamber formed between the first rib 310 and the second rib 320 as an example. The vibration absorption assembly includes a mass block, a first coil spring 410 and a second coil spring 420. The mass block includes a hinged plate 431 and a mass block body 432 arranged at the free end of the hinged plate 431. Two identical hinge rings 500 are welded to the surface of the inner arc plate 100. The two hinge rings 500 are symmetrically arranged at either end of the width direction of the outer wall of the inner arc plate 100. The hinge plate 431 is mounted on the inner arc plate 100 via the hinge rings 500. Specifically, hinge shafts are provided on both sides of the width direction of the hinge plate 431 near one end of the inner arc plate 100, which are designed to extend into the two hinge rings 500. The diameter of the hinge shafts is smaller than the inner diameter of the hinge rings 500, and the hinge plate 431 and the mass body 432 can rotate about the hinge rings 500. The circumferential distance between the axis of the hinge shafts and the first rib 310 is equal to the circumferential distance between the axis of the hinge shafts and the second rib 320. The mass block body 432 is welded to the free end of the hinge plate 431, and there is a gap between the inner wall of the outer arc plate 200 and the mass block body 432. When the medium inside the pipeline is at high temperature, the hinge plate 431 of the vibration absorber will experience significant radial expansion and displacement due to the thermal expansion effect of the metal. The appropriate gap between the mass block body 432 and the outer arc plate 200 ensures the free movement of the mass block. One end of the first coil spring 410 is welded to the hinge plate 431, and the other end of the first coil spring 410 is welded to the first rib 310. One end of the second coil spring 420 is welded to the hinge plate 431, and the other end of the second coil spring 420 is welded to the second rib 320. The stiffness of the first coil spring 410 and the second coil spring 420 on both sides of the hinge plate 431 is equal. The vibration-absorbing chamber formed between the second and third ribs 320 and 330 also has a similar structure. In short, within each vibration-absorbing chamber, the hinged plate and the mass body correspond to two coil springs. The two ribs within a vibration-absorbing chamber simultaneously withstand the reaction forces generated by the compression and extension of the coil springs. In the original state, the two hinged plates and the two mass bodies within a vibration-absorbing shell are also separated by a quarter of a circumference.

[0045] The multi-directional tunable dynamic vibration absorption device for pipelines in this embodiment consists of two vibration absorption units, each comprising a semi-circular vibration absorption shell. The two shells are snap-fitted and fixed to the pipeline. Each shell has two vibration absorption chambers, each composed of two ribs, an outer arc plate, and an inner arc plate. Adjacent ribs are spaced a quarter of a circumference apart. Each vibration absorption chamber comprises a vibration absorption assembly consisting of a mass body, a hinged plate, and two coil springs. Consequently, each vibration absorption shell comprises two mass bodies, two hinged plates, and four coil springs. Initially, the two hinged plates and adjacent mass bodies in a vibration absorption shell are spaced a quarter of a circumference apart. The vibration absorption device thus comprises four vibration absorption chambers: the first, second, third, and fourth chambers, arranged clockwise. The first and third chambers are symmetrically arranged along the radial direction of the pipeline, while the second and fourth chambers are symmetrically arranged along the radial direction of the pipeline. Clearly, four mass bodies, four hinged plates, and eight coil springs are installed. Specifically, the coil springs on both sides of a hinged plate have equal stiffness. By adjusting the mass body weight and coil spring stiffness, optimal frequency synchronization can be achieved, thereby maximizing vibration reduction. This multi-directionally tunable dynamic vibration absorption device for pipelines is arranged symmetrically, with each hinged plate, mass body, and hinged plate spaced a quarter of the way apart. This achieves bidirectional vibration reduction along the pipeline's radial direction. Furthermore, by adjusting the mounting angle, such as aligning one hinged plate perpendicular to the direction of maximum vibration displacement (the maximum vibration displacement and direction can be determined using a conventional vibration meter), maximum vibration reduction can be achieved.

[0046] Confirmation of design parameters of pipeline multi-directional tunable dynamic vibration absorption device:

[0047] Taking the reduction of the vibration displacement amplitude of a pipeline in a certain direction as an example, the design parameter calculation process is as follows:

[0048] 1) First, according to the expected vibration reduction effect of the pipeline, the ratio of the mass block body to the pipeline weight is determined according to formulas (1) to (3), and then the mass M of the mass block body is determined; where X is the expected vibration displacement value, X st is the vibration displacement value of the pipeline, μ is the mass ratio, M S is the ratio of the pipe mass.

[0049] (X / X st )=0.827(μ+0.02) -0.62 (1)

[0050]

[0051]

[0052] 2) Determine the frequency ratios λ1 and λ2 of the mass block and spring assembly of the vibration absorber by using the empirical optimal demodulation formulas (4) to (7), and then determine the natural frequency; where λ1 and λ2 are the ratios of the natural frequencies f1 and f2 of the two symmetrical assemblies to the pipeline vibration frequency 1f0, where 1f0 is obtained through field testing.

[0053] λ1=0.403(μ+0.131) -0.437 (4)

[0054] λ2=-0.72μ+1.03 (5)

[0055] f1=λ1f0 (6)

[0056] f2=λ2f0 (7)

[0057] 3) Using formulas (8) and (9), calculate the spring stiffness K1 and K2, where K1 is the spring stiffness corresponding to one of the hinged plates / mass blocks, and K2 is the spring stiffness of the hinged plates / mass blocks at symmetrical positions. The two hinged plates are in the same plane.

[0058]

[0059]

[0060] About the assembly of the multi-directional tunable dynamic vibration absorption device for pipelines:

[0061] The assembly process is as follows:

[0062] 1) Based on the weight M of the mass block and the installation space on site, determine the length, width and thickness of the mass block body, and then determine the radius of the outer arc plate;

[0063] 2) Determine the length of the first, second, and third ribs, which is equal to the radius of the outer arc plate minus the radius of the inner arc plate;

[0064] 3) Determine the length of the hinge plate, which is equal to the radius of the outer arc plate - the radius of the inner arc plate - the length of the mass block - the reserved space;

[0065] 4) According to K1, K2 and the radius of the outer arc plate, determine the length, wire diameter, spacing and other parameters of the coil spring and select the appropriate coil spring product;

[0066] 5) Welding the hinge plate to the mass body, wherein the welding position coincides with the center line of the mass block;

[0067] 6) The hinge plate and the inner arc plate are connected together through a hinge ring, wherein the hinge ring is welded to the inner arc plate, and the hinge plate can rotate freely around the hinge ring;

[0068] 7) Weld the first, second, and third ribs to the inner arc plate, with each rib spaced 45° apart;

[0069] 8) Weld the coil spring to the hinge plate and the ribs on both sides;

[0070] 9) Install the outer arc plate.

[0071] This embodiment also discloses a method for multi-directionally tunable dynamic vibration absorption of pipelines. After assembling the multi-directionally tunable dynamic vibration absorption device for pipelines, it is fixed on the pipeline for vibration absorption. During use, the installation angle of the vibration absorption device can be adjusted according to the maximum vibration displacement and direction of the pipeline obtained by the vibration meter. For example, one of the hinged plates can be perpendicular to the direction of the maximum vibration displacement to achieve the maximum vibration reduction effect.

[0072] The above embodiments are intended only to illustrate the technical concepts and features of the present invention. Their purpose is to enable those skilled in the art to understand the contents of the present invention and implement them accordingly. They are not intended to limit the scope of protection of the present invention. Any equivalent changes or modifications made in accordance with the spirit of the present invention are intended to be covered by the scope of protection of the present invention.

Claims

1. A design method for a multi-directional tunable dynamic vibration absorption device for a pipeline, characterized in that: The steps include: 1) First, according to the expected vibration reduction effect of the pipeline, the ratio of the mass block body to the pipeline weight is determined according to formulas (1) to (3), and then the mass M of the mass block body is determined; where X is the expected vibration displacement value, X st is the vibration displacement value of the pipeline, μ is the mass ratio, M S is the ratio of the pipeline mass; (X / X st )=0.827(μ+0.02) -0.62 (1) 2) Determine the frequency ratios λ1 and λ2 of the mass block and spring assembly of the vibration absorber by using the empirical optimal demodulation formulas (4) to (7), and then determine the natural frequency; where λ1 and λ2 are the ratios of the natural frequencies f1 and f2 of the two symmetrical assemblies to the pipeline vibration frequency 1f0 respectively; λ1=0.403(μ+0.131) -0.437 (4) λ2=-0.72μ+1.03 (5) f1=λ1f0 (6) f2=λ2f0 (7) 3) Using formulas (8) and (9), calculate the spring stiffness K1 and K2, where K1 is the spring stiffness corresponding to one of the hinged plates / mass blocks, and K2 is the spring stiffness of the hinged plates / mass blocks at symmetrical positions. The two hinged plates are located in the same plane.

2. A multi-directional tunable dynamic vibration absorbing device for pipelines designed by the design method according to claim 1, characterized in that: The invention comprises two vibration absorbing units arranged on the outer wall of the pipe, each of the vibration absorbing units comprises a vibration absorbing shell in the shape of a semicircular ring, the vibration absorbing shell comprises an inner circular arc plate, an outer circular arc plate and a plurality of ribs, the plurality of ribs are arranged between the inner circular arc plate and the outer circular arc plate along the radial direction of the vibration absorbing shell, and a vibration absorbing chamber for installing a vibration absorbing assembly is formed between two adjacent ribs, the vibration absorbing assembly comprises a mass block and an elastic member, the mass block is rotatably arranged on the inner circular arc plate, and the elastic member is arranged between the mass block and the ribs.

3. The pipeline multi-directional tunable dynamic vibration absorption device according to claim 2 is characterized in that: The mass block includes a hinge plate and a mass block body. The hinge plate is rotatably arranged on the inner arc plate, and the mass block body is arranged at the free end of the hinge plate.

4. The pipeline multi-directional tunable dynamic vibration absorption device according to claim 3 is characterized in that: The inner arc plate is provided with a hinge ring, the hinge plate is provided on the inner arc plate through the hinge ring, and the mass block body can rotate around the hinge ring.

5. The pipeline multi-directional tunable dynamic vibration absorbing device according to claim 4 is characterized in that: There are two hinge rings, and the two hinge rings are symmetrically arranged at both ends of the width direction of the outer wall surface of the inner circular arc plate. Hinge circular shafts for extending into the hinge rings are provided on both sides of the width direction of one end of the hinge plate close to the inner circular arc plate, and the diameter of the hinge circular shaft is smaller than the inner diameter of the hinge ring.

6. The pipeline multi-directional tunable dynamic vibration absorbing device according to claim 5, characterized in that: The circumferential distance between the axis of the hinged circular shaft and one of the two ribs is equal to the circumferential distance between the axis of the hinged circular shaft and the other of the two ribs.

7. The pipeline multi-directional tunable dynamic vibration absorbing device according to claim 6, characterized in that: The elastic members are arranged on both sides of the hinge plate.

8. The pipeline multi-directional tunable dynamic vibration absorbing device according to claim 7, characterized in that: The elastic member is a coil spring, one end of the coil spring acts on the hinge plate, and the other end of the coil spring acts on the rib plate.

9. The pipeline multi-directional tunable dynamic vibration absorbing device according to claim 8, characterized in that: The stiffness of the two coil springs on both sides of the hinge plate is equal.

10. The pipeline multi-directional tunable dynamic vibration absorbing device according to claim 9, characterized in that: There is a distance between the inner wall surface of the outer arc plate and the mass block body.

11. The pipeline multi-directional tunable dynamic vibration absorbing device according to claim 10, characterized in that: There are three ribs, and the interval between two adjacent ribs is one quarter of a circle.

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