Active vibration reduction damper for oil field well drilling

Abstract

The invention discloses an active vibration reduction damper for oil field drilling, and belongs to the technical field of oil field drilling equipment, the active vibration reduction damper comprises an upper damping shell and a lower damping shell, the upper damping shell and the lower damping shell are mutually sleeved, and a grouting conveying pipe is arranged in the upper damping shell and the lower damping shell; a driving rod frame is installed on the grouting conveying pipe, a primary vibration reduction assembly and a multi-stage vibration reduction assembly are arranged in the lower damping shock absorption shell, a fixing disc is arranged above the primary vibration reduction assembly and the multi-stage vibration reduction assembly, and the fixing disc is fixedly connected into the upper damping shock absorption shell. By means of the primary vibration reduction assembly, the vibration reduction requirement can be met when the vibration amplitude is small, when the vibration amplitude exceeds a preset threshold value, the multi-stage vibration reduction assembly is started to achieve stepped step-by-step vibration reduction, the overall vibration reduction capacity is improved, the problem of vibration reduction failure caused by dynamic changes of the vibration amplitude in the well drilling process is effectively solved, and stable operation of well drilling equipment is guaranteed.

Description

Technical Field

[0001] This invention relates to the field of oilfield drilling technology, and in particular to an active vibration damper for oilfield drilling. Background Technology

[0002] During oilfield drilling, drilling equipment is prone to severe vibrations due to factors such as changes in formation lithology, drill bit cutting impact, and high-speed equipment operation. This vibration not only exacerbates the wear of core components like drill pipes and drill bits, shortening equipment lifespan and increasing maintenance costs, but also causes fluctuations in drilling parameters, affecting the precise control of the wellbore trajectory, reducing drilling efficiency, and even triggering safety accidents such as wellbore collapse and stuck pipe. Therefore, vibration reduction is a crucial element in ensuring the safe and efficient progress of oilfield drilling operations. However, traditional oilfield drilling vibration reduction devices are mostly single-structure vibration reduction devices, only effective within a specific amplitude range. They struggle to accurately adapt to the dynamic changes in amplitude during drilling, resulting in unstable vibration reduction effects. While some devices are equipped with damping fluid for auxiliary vibration reduction, the resistance of the damping fluid is often fixed and cannot be dynamically adjusted according to the amplitude. When the amplitude increases sharply, insufficient resistance can lead to vibration reduction failure, failing to meet the oilfield drilling requirements for "wide amplitude adaptation and efficient and stable vibration reduction," thus hindering the improvement of drilling operation quality and efficiency.

[0003] To address the above problems, this invention proposes an active vibration damper for oilfield drilling. Summary of the Invention

[0004] The purpose of this invention is to address the shortcomings of traditional oilfield drilling vibration damping devices, which are mostly single vibration damping structures that can only function within a specific amplitude range. Although some devices are equipped with damping fluid for auxiliary vibration damping, the resistance of the damping fluid is mostly a fixed value and cannot be dynamically adjusted according to the amplitude. When the amplitude increases suddenly, the damping is prone to failure due to insufficient resistance. Therefore, this invention proposes an active vibration damping device for oilfield drilling.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: An active vibration damper for oilfield drilling includes an upper damping shell and a lower damping shell, which are nested together. A grouting delivery pipe is provided in the upper and lower damping shells, and a drive rod is installed on the grouting delivery pipe. A primary vibration damping component and a multi-stage vibration damping component are provided in the lower damping shell. A fixing plate is provided above the primary vibration damping component and the multi-stage vibration damping component, and the fixing plate is fixedly connected to the upper damping shell. The upper damping shock absorber shell is provided with a damping buffer cavity, and the damping buffer cavity is provided with a hydraulic damping shock absorber assembly. The damping buffer cavity is connected to multiple flow regulating assemblies. The toothed valves of the multiple flow regulating assemblies mesh with the toothed disc for transmission. The toothed disc is provided with multiple straight grooves and multiple inclined grooves. The straight grooves and inclined grooves are connected to each other. The drive rod frame can slide in the straight grooves and inclined grooves.

[0006] Preferably, the grouting delivery pipe is installed through the fixed plate, and the section of the grouting delivery pipe located in the upper damping shock absorber shell is a flexible hose.

[0007] Preferably, a reinforcing ring is fixedly connected to the drive rod frame.

[0008] Preferably, the primary vibration damping component includes a first disc spring, which is sleeved on the grouting delivery pipe.

[0009] Preferably, the first disc spring is composed of multiple combined conical washers, with the upper and lower combined conical washers overlapping the bottom walls of the fixed plate and the lower damping shock absorber shell, respectively. The combined conical washers are stacked on top of each other, and a damping ring is provided between the two lowest combined conical washers, which is sleeved on the grouting conveying pipe.

[0010] Preferably, the multi-stage vibration damping component includes two sets of second disc springs, each set containing multiple second disc springs, and also composed of multiple combined conical washers, with the number of combined conical washers in the two sets of second disc springs increasing sequentially from the outside to the inside.

[0011] Preferably, the second disc spring is sleeved on the damping column, which is located between the bottom wall of the fixed plate and the lower damping shock absorber shell. An installation ring is sleeved on the damping column, with the upper installation ring in contact with the fixed plate. A limiting ring for limiting the installation ring is installed on the damping column, and a combined conical washer of the second disc spring is located between the two installation rings.

[0012] Preferably, a bottom ring is stacked below one of the sets of second disc springs, and a set of damping columns on the outer side is provided through the bottom ring.

[0013] Preferably, the toothed disc is rotatably mounted on the fixed ring via a bearing, and the fixed ring is fixedly connected to the upper damping shock absorber housing. The flow regulating assembly includes a regulating pipe, which passes through the fixed ring and has its two ends connected to the upper and lower sides of the damping buffer cavity, respectively. A toothed valve is provided on the regulating pipe.

[0014] Preferably, the hydraulic damping shock absorber assembly includes a damping plug structure disposed in a damping buffer cavity. Multiple damping rod structures are fixedly connected to the lower part of the damping plug structure. The multiple damping rod structures extend out of the upper damping shock absorber shell and are fixedly connected to the bottom wall of the lower damping shock absorber shell.

[0015] This invention provides an active vibration damper for oilfield drilling, which has the following advantages: This active vibration damper for oilfield drilling can meet the vibration reduction requirements when the vibration amplitude is small through the primary vibration damping component. When the amplitude exceeds the preset threshold, the multi-stage vibration damping component is activated to achieve step-by-step vibration reduction, improve the overall vibration reduction capability, effectively solve the problem of vibration reduction failure caused by dynamic changes in amplitude during drilling, and ensure the stable operation of drilling equipment. This active vibration damper for oilfield drilling uses the relative movement between the upper and lower damping shells to enable hydraulic damping components to work with the flow regulation components to achieve hydraulic vibration reduction. This allows for flexible vibration reduction when the amplitude is small. When the amplitude increases, the drive rod enters the inclined groove, which drives the toothed disc to adjust the flow of the flow regulation components. By gradually reducing the flow cross-section of the damping fluid, the resistance of the damping fluid is gradually increased, so that the damping force is precisely matched with the vibration load. This effectively absorbs the impact energy generated by large-amplitude vibration, reduces the impact force of vibration on drilling equipment, and prevents core components from being damaged by severe impact. This active vibration damper for oilfield drilling provides a stable foundation for damping fluid resistance adjustment through the graded activation of a primary damping component in conjunction with a multi-stage damping component. The primary damping component initially buffers the vibration, reserving response time for the gradual increase in damping fluid resistance and avoiding secondary impacts caused by a sudden increase in resistance. The drive rod moves into the inclined groove, causing the gear disc and flow regulation component to adjust the flow area of ​​the damping fluid in conjunction. The dynamic adjustment of damping fluid resistance compensates for the stiffness abruptness defect of the graded damping module. The flexible resistance transition makes the switching between the primary and graded damping components smoother. At the same time, in large amplitude scenarios, it forms a combined force with the multi-stage damping components to ensure precise synchronization of vibration reduction, thereby achieving amplitude adaptation, rapid response, and efficient vibration reduction functions, providing a reliable guarantee for the safe and efficient advancement of oilfield drilling operations. Attached Figure Description

[0016] Figure 1 This is a perspective view of an active vibration damper for oilfield drilling proposed in this invention; Figure 2 This is a three-dimensional cross-sectional view of an active vibration damper for oilfield drilling proposed in this invention; Figure 3 This is a perspective view of the upper damping housing of an active vibration damper for oilfield drilling proposed in this invention; Figure 4 This is a perspective view of the connection between the primary vibration damping component and the grouting delivery pipe of an active vibration damper for oilfield drilling proposed in this invention. Figure 5 This is a perspective view of a multi-stage vibration damping component of an active vibration damper for oilfield drilling proposed in this invention; Figure 6 This is a cross-sectional perspective view of a multi-stage vibration damping component of an active vibration damper for oilfield drilling proposed in this invention; Figure 7 This is a three-dimensional cross-sectional view of the upper damping shock absorber shell of an active vibration damper for oilfield drilling proposed in this invention; Figure 8 This is a three-dimensional cross-sectional view of a hydraulic damping component of an active vibration damper for oilfield drilling proposed in this invention. Figure 9 This is a perspective view of the toothed disc of an active vibration damping device for oilfield drilling proposed in this invention; Figure 10 In this invention Figure 9 A magnified view of point A.

[0017] In the diagram: 100, Upper damping shock absorber shell; 200, Lower damping shock absorber shell; 300, Hydraulic damping shock absorber assembly; 301, Damping plug structure; 302, Damping rod structure; 400, Damping buffer chamber; 500, Grouting delivery pipe; 600, Multi-stage vibration damping assembly; 601, Vibration damping column; 602, Bottom ring; 603, Second disc spring; 604, Limiting ring; 605, Mounting ring; 700, Drive rod frame; 800, Flow regulation assembly; 801, Regulation pipe; 802, Gear valve; 900, Primary vibration damping assembly; 901, First disc spring; 902, Vibration damping ring; 110, Reinforcing ring; 111, Gear disc; 112, Inclined groove; 113, Fixed disc; 114, Straight groove; 115, Fixed ring. Detailed Implementation

[0018] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0019] In the description of this invention, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0020] Example 1: Refer to Figures 1-7An active vibration damper for oilfield drilling includes an upper damping shell 100 and a lower damping shell 200, which are nested together. A grouting delivery pipe 500 is installed within each shell. The grouting delivery pipe 500 passes through a fixing plate 113, and the section of the grouting delivery pipe 500 in the upper shell 100 is a flexible hose. This flexible hose facilitates grout delivery and injection operations and prevents damage from vibration. A drive rod 700 is mounted on the grouting delivery pipe 500. The lower damping shell 200 contains a primary vibration damping assembly 900 and a multi-stage vibration damping assembly 600. The primary vibration damping assembly 900 includes a first disc spring 901. The grouting delivery pipe 500 and the multi-stage vibration damping assembly 600... The elastic deformation of the two disc springs 603 absorbs energy, transforming instantaneous high loads into continuous low stress, thus preventing drilling equipment from being damaged by impact. It can optimize the vibration absorption effect and reduce the risk of resonance. The first disc spring 901 is sleeved on the grouting delivery pipe 500. The first disc spring 901 is composed of multiple combined conical washers. The upper and lower combined conical washers overlap with the bottom wall of the fixed plate 113 and the lower damping shock absorber shell 200, respectively. The combined conical washers are stacked on top of each other, and a damping ring 902 is provided between the two lowest combined conical washers. By making the hole between the damping ring 902 and the damping column 601 larger than the diameter of the limiting ring 604, when the vibration amplitude increases, the damping ring 902 can apply an upward impact force to the multi-stage damping assembly 600, thereby enabling multi-stage damping operations. The damping ring 902 is sleeved on the grouting delivery pipe 500. The multi-stage vibration damping assembly 600 includes two sets of second disc springs 603, each set containing multiple second disc springs 603, each also composed of multiple combined conical washers. The number of combined conical washers in the two sets of second disc springs 603 increases sequentially from the outside to the inside. By increasing the number of second disc springs 603 from the outside to the inside, a step-by-step vibration damping effect can be achieved from the inside to the outside, meeting the vibration damping requirements of different amplitudes. The second disc springs 603 are sleeved on the damping column 601, which is located between the fixed plate 113 and the bottom wall of the lower damping shock absorber shell 200. An installation ring 605 is sleeved on the damping column 601, with the upper installation ring 605 contacting the fixed plate 113. A limiting ring 604 is installed on the damping column 601 to limit the installation ring 605, preventing the combined conical washers from being moved. To address the issue of the ring detaching and causing the progressive vibration damping effect to fail, a combination conical washer of the second disc spring 603 is placed between two mounting rings 605. A bottom ring 602 is stacked below one set of second disc springs 603. The diameter of the central hole of the bottom ring 602 is larger than the diameter of the first disc spring 901, allowing the first disc spring 901 to perform initial vibration damping smoothly. The bottom ring 602 is also fitted onto the outer set of damping rings 902, and the hole is also larger than the diameter of the limiting ring 604. As the amplitude increases, the bottom ring 602 can smoothly contact the outer second disc spring 603, thus achieving a multi-stage vibration damping effect. A set of damping columns 601 on the outer side is inserted through the bottom ring 602. A fixing plate 113 is provided above the primary damping component 900 and the multi-stage damping component 600, and the fixing plate 113 is fixedly connected to the upper damping shock absorber shell 100.

[0021] In this embodiment: the primary vibration damping component 900 can meet the vibration damping requirements when the vibration amplitude is small. When the amplitude exceeds the preset threshold, the vibration damping ring 902 contacts the multi-stage vibration damping component 600 upward, so that the multi-stage vibration damping component 600 can achieve step-by-step vibration damping from the inside out through two sets of second disc springs 603, thereby improving the overall vibration damping capacity, effectively solving the problem of vibration damping failure caused by dynamic changes in amplitude during drilling, and ensuring the stable operation of drilling equipment.

[0022] Example 2: Refer to Figures 7-10An active vibration damper for oilfield drilling includes an upper damping housing 100, within which a damping buffer chamber 400 is provided. The damping buffer chamber 400 stores damping fluid. A hydraulic damping damping assembly 300 is disposed within the damping buffer chamber 400, including a damping plug structure 301 located within the damping buffer chamber 400. Multiple damping rod structures 302 are fixedly connected below the damping plug structure 301. Sealing rings or other sealing rings are added to the portions of the damping rod structures 302 that pass through the upper damping housing 100. The sealing method prevents leakage. Multiple damping rod structures 302 extend through the upper damping housing 100 and are fixedly connected to the bottom wall of the lower damping housing 200. The damping buffer cavity 400 is connected to multiple flow regulating components 800. Each flow regulating component 800 includes a regulating pipe 801, through which a fixing ring 115 passes. Both ends of the regulating pipe 801 are connected to the upper and lower sides of the damping buffer cavity 400, respectively. The regulating pipe 801 allows the damping fluid to flow vertically within the damping buffer cavity 400. A toothed valve is provided on the regulating pipe 801. 802, the gear valves 802 of the multiple flow regulating components 800 mesh with the gear disc 111 for transmission. The rotation of the gear disc 111 allows for transmission with the gear valves 802. Thus, as the amplitude increases, the flow rate of the adjustable damping fluid by the gear valves 802 is dynamically adjusted to meet the vibration reduction requirements under different amplitudes. The gear disc 111 is rotatably mounted on a fixed ring 115 via bearings. The gear disc 111 can rotate stably through the bearings, ensuring stable transmission between the gear disc 111 and the gear valves 802. The fixed ring 115 is fixedly connected to the upper damping shock absorber housing 100. The gear disc 111 has multiple straight grooves 114 and multiple inclined grooves 11. 2. The straight groove 114 ensures the movement of the drive rod 700 and can achieve a preliminary hydraulic damping effect during primary vibration reduction. When the drive rod 700 enters the inclined groove 112, it can drive the gear plate 111 to rotate. The damping fluid can be adjusted through the gear valve 802 to meet the requirements of dynamic vibration reduction. The straight groove 114 and the inclined groove 112 are connected, and the drive rod 700 can slide in the straight groove 114 and the inclined groove 112. A reinforcing ring 110 is fixedly connected to the drive rod 700. The reinforcing ring 110 can reinforce the drive rod 700 and ensure its stability.

[0023] In this embodiment: the relative movement between the upper damping housing 100 and the lower damping housing 200 enables the hydraulic damping shock absorption assembly 300 to work with the flow regulating assembly 800 to achieve hydraulic vibration reduction. This satisfies the requirement of flexible vibration reduction when the amplitude is small. When the amplitude increases, the drive rod 700 enters the inclined groove 112, which drives the gear disc 111 and the gear valve 802. The gear valve 802 regulates the flow rate of the damping fluid in the regulating pipe 801. By gradually reducing the flow cross section of the damping fluid, the resistance of the damping fluid is gradually increased, so that the damping force is precisely matched with the vibration load. This effectively absorbs the impact energy generated by large-amplitude vibration, reduces the impact force of vibration on the drilling equipment, and avoids damage to core components due to severe impact.

[0024] Example 3: Reference Figures 1-5 , Figure 7 and Figures 9-10 An active vibration damper for oilfield drilling includes an upper damping shell 100 and a lower damping shell 200, which are nested together. A grouting delivery pipe 500 is provided in the upper damping shell 100 and the lower damping shell 200, and a drive rod frame 700 is installed on the grouting delivery pipe 500. A primary vibration damping component 900 and a multi-stage vibration damping component 600 are provided in the lower damping shell 200. A fixing plate 113 is provided above the primary vibration damping component 900 and the multi-stage vibration damping component 600, and the fixing plate 113 is fixedly connected to the upper damping shell 100. The upper damping shock absorber housing 100 is provided with a damping buffer cavity 400, and the damping buffer cavity 400 is provided with a hydraulic damping shock absorber assembly 300. The damping buffer cavity 400 is connected to multiple flow regulating assemblies 800. The toothed valves 802 of the multiple flow regulating assemblies 800 mesh with the toothed disc 111 for transmission. Multiple straight grooves 114 and multiple inclined grooves 112 are opened on the toothed disc 111. The straight grooves 114 and inclined grooves 112 are connected. The drive rod frame 700 can slide in the straight grooves 114 and inclined grooves 112.

[0025] In this embodiment, the primary vibration damping component 900, in conjunction with the multi-stage vibration damping component 600, provides a stable foundation for the adjustment of damping fluid resistance through graded activation. The primary vibration damping component 900 first buffers the vibration, reserving response time for the gradual increase of damping fluid resistance and avoiding secondary impacts caused by a sudden increase in resistance. The drive rod 700 moves into the inclined groove 112, causing the gear disc 111 to work in conjunction with the flow regulation component 800 to adjust the flow area of ​​the damping fluid. The dynamic adjustment of the damping fluid resistance compensates for the stiffness abruptness defect of the graded vibration damping module. The transition of flexible resistance makes the switching between the primary vibration damping component 900 and the graded vibration damping component smoother. At the same time, in large amplitude scenarios, it forms a combined force with the multi-stage vibration damping component 600 to ensure precise synchronization of vibration damping operation, thereby achieving the functions of amplitude adaptation, rapid response, and efficient vibration damping, providing a reliable guarantee for the safe and efficient advancement of oilfield drilling operations.

[0026] When the drilling equipment is subjected to vibration reduction, the upper damping shell 100 and the lower damping shell 200 move relative to each other, causing the first disc spring 901 to perform initial vibration reduction and buffering, and the damping plug structure 301 moves, causing the damping fluid to flow in the damping buffer cavity 400 through the regulating pipe 801, thereby assisting in achieving flexible vibration reduction. When the vibration amplitude is large, the first disc spring 901 drives the damping ring 902 to move upward, thereby achieving step-by-step vibration reduction through two sets of second disc springs 603 from the inside out. At the same time, the grouting delivery pipe 500 can drive the drive rod frame 700 to move. The drive rod frame 700 enters the inclined groove 112 and drives the gear plate 111 to rotate through the inclined groove 112. The gear plate 111 is driven by the gear valve 802. The gear valve 802 adjusts the flow rate of the damping fluid inside the regulating pipe 801, thereby gradually reducing the flow cross section of the damping fluid and effectively reducing the vibration of the drilling equipment.

Claims

1. An active vibration damper for oilfield drilling, comprising an upper damping shell (100) and a lower damping shell (200), characterized in that, The upper damping shock absorber shell (100) and the lower damping shock absorber shell (200) are nested together. A grouting delivery pipe (500) is provided in the upper damping shock absorber shell (100) and the lower damping shock absorber shell (200). A drive rod frame (700) is installed on the grouting delivery pipe (500). A primary vibration damping component (900) and a multi-stage vibration damping component (600) are provided in the lower damping shock absorber shell (200). A fixing plate (113) is provided above the primary vibration damping component (900) and the multi-stage vibration damping component (600). The fixing plate (113) is fixedly connected in the upper damping shock absorber shell (100). The upper damping shock absorber shell (100) is provided with a damping buffer cavity (400), and the damping buffer cavity (400) is provided with a hydraulic damping shock absorber assembly (300). The damping buffer cavity (400) is connected to multiple flow regulating assemblies (800). The toothed valves (802) of the multiple flow regulating assemblies (800) mesh with the toothed disc (111) for transmission. The toothed disc (111) is provided with multiple straight grooves (114) and multiple inclined grooves (112). The straight grooves (114) and inclined grooves (112) are connected. The drive rod frame (700) can slide in the straight grooves (114) and inclined grooves (112).

2. The active vibration damper for oilfield drilling according to claim 1, characterized in that, The grouting delivery pipe (500) is installed through the fixing plate (113), and the section of the grouting delivery pipe (500) located in the upper damping shock absorber shell (100) is a flexible hose.

3. The active vibration damper for oilfield drilling according to claim 1, characterized in that, A reinforcing ring (110) is fixedly connected to the drive rod frame (700).

4. The active vibration damper for oilfield drilling according to claim 1, characterized in that, The primary vibration damping assembly (900) includes a first disc spring (901), which is sleeved on the grouting delivery pipe (500).

5. An active vibration damper for oilfield drilling according to claim 4, characterized in that, The first disc spring (901) is composed of multiple combined conical washers. The upper and lower combined conical washers overlap with the bottom wall of the fixed plate (113) and the lower damping shock absorber shell (200), respectively. The combined conical washers are superimposed on each other, and a damping ring (902) is provided between the two lowest combined conical washers. The damping ring (902) is sleeved on the grouting conveying pipe (500).

6. The active vibration damper for oilfield drilling according to claim 1, characterized in that, The multi-stage vibration damping assembly (600) includes two sets of second disc springs (603), each set of second disc springs (603) has multiple components, and is also composed of multiple combined conical washers, and the number of combined conical washers of the two sets of second disc springs (603) increases sequentially from the outside to the inside.

7. An active vibration damper for oilfield drilling according to claim 6, characterized in that, The second disc spring (603) is sleeved on the damping column (601), which is located between the fixed plate (113) and the bottom wall of the lower damping shock absorber shell (200). The damping column (601) is sleeved with an installation ring (605), the upper installation ring (605) is in contact with the fixed plate (113), and a limiting ring (604) is installed on the damping column (601) to limit the installation ring (605). The combined conical washer of the second disc spring (603) is located between the two installation rings (605).

8. An active vibration damper for oilfield drilling according to claim 7, characterized in that, A bottom ring (602) is stacked below one of the second disc springs (603), and a set of damping columns (601) on the outer side are inserted through the bottom ring (602).

9. An active vibration damper for oilfield drilling according to claim 1, characterized in that, The gear disc (111) is rotatably mounted on the fixed ring (115) via a bearing, and the fixed ring (115) is fixedly connected in the upper damping shock absorber shell (100). The flow regulating assembly (800) includes a regulating pipe (801), which passes through the fixed ring (115) and is connected to the upper and lower sides of the damping buffer cavity (400) at both ends. A gear valve (802) is provided on the regulating pipe (801).

10. An active vibration damper for oilfield drilling according to claim 9, characterized in that, The hydraulic damping shock absorber assembly (300) includes a damping plug structure (301), which is disposed in a damping buffer cavity (400). Multiple damping rod structures (302) are fixedly connected to the lower part of the damping plug structure (301). The multiple damping rod structures (302) extend out of the upper damping shock absorber shell (100) and are fixedly connected to the bottom wall of the lower damping shock absorber shell (200).

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