Air flexible supporting tilting pad bearing with interlayer type damping structure and manufacturing method

Abstract

The invention relates to the technical field of air bearings, in particular to an air flexible supporting tilting pad bearing with an interlayer type damping structure and a manufacturing method, the air flexible supporting tilting pad bearing comprises a bearing outer ring, and four tilting pads are connected to the inner side of the bearing outer ring through four sets of damping structures; the damping structure comprises a swing spring, and an interlayer type damping layer is arranged in the swing spring. An air inlet hole communicated with an external air supply channel is formed in the end face of the tilting pad, a pressure equalizing groove is formed in the inner side face of the tilting pad, and a capillary throttling hole communicated with the air inlet hole is formed in the pressure equalizing groove; the high-strength and high-toughness alloy steel and the nitrile rubber with good elasticity and oil resistance are effectively combined, so that the bearing capacity and the overall stability of the bearing structure are enhanced, and meanwhile, the vibration reduction and buffering characteristics of the bearing structure are remarkably improved; the multi-material collaborative design is beneficial to improving the operation reliability and prolonging the service life of a bearing system, and the comprehensive performance requirement for a high-performance vibration reduction supporting component under the complex working condition is met.

Description

Technical Field

[0001] The present invention relates to the technical field of air bearings, and in particular to an air flexible support tilting pad bearing with a sandwich damping structure and a manufacturing method thereof. Background Art

[0002] In the process of industrial development, mechanical equipment is constantly developing, and at the same time, it also drives the development of industry. Rotating machinery occupies a pivotal position in mechanical equipment, and bearings, as essential basic components in rotating machinery, play a role in reducing friction, improving efficiency and supporting transmission parts in mechanical transmission. The performance of bearings has an important impact on the development of rotating machinery. The performance of bearings directly determines the efficiency, vibration and noise, life, reliability and safety of the main machine. Among them, gas bearings have many advantages such as high speed, high power density, oil-free and maintenance-free. They have been successfully applied to high-speed and high-temperature turbomachinery such as air cycle machines and micro gas turbines, and have broad development prospects. At present, the use of gas bearings in China is still limited to light load and low temperature occasions, and the air bearings used have low air damping, resulting in large vibration and poor stability of the bearings.

[0003] Therefore, how to improve the damping performance of sliding bearings without significantly increasing system complexity remains a question worth studying. In recent years, constrained damping structures (CDSs) have been widely used in vibration control due to their excellent energy dissipation capabilities. Considering that CDSs can effectively improve the damping performance of the system while maintaining a high load capacity, their introduction into the field of air bearings may provide a new technical path for bearing vibration reduction. Summary of the Invention

[0004] The purpose of the present invention is to provide an air-flexibly supported tilting pad bearing with a sandwich damping structure and a manufacturing method thereof, which can effectively improve the damping performance of the system through a constrained damping structure and improve the damping characteristics and seismic performance of the bearing.

[0005] Based on the above purpose, the present invention adopts the following technical solutions: An air-flexible support tilting pad bearing with a sandwich damping structure comprises an outer ring of the bearing, and four tilting pads are evenly distributed on the inner side of the outer ring of the bearing, characterized in that: each of the tilting pads is connected to the inner ring of the bearing by a damping structure, and each of the damping structures comprises a pair of swing springs; the swing spring is a sandwich structure, and a cavity is provided inside it, and the cavity is filled with damping material to form a damping layer; the opening angle of each tilting pad is the same, and the tilting pads are arranged with a clearance fit with each other; a pressure equalizing groove is provided on the side of the tilting pad close to the central axis of the outer ring of the bearing, and an air inlet is provided on the end face of the tilting pad; the air inlet holes of the four tilting pads are respectively connected to four external air supply channels, or: the air inlet holes on two adjacent tilting pads are connected in parallel to one external air supply channel, and the air inlet holes on the other two adjacent tilting pads are connected in parallel to a second external air supply channel.

[0006] Preferably, the swing spring is an S-shaped structure, and the two ends of the swing spring are fixedly connected to the inner side surface of the bearing outer ring and the outer side surface of the tilting pad respectively; the internal cavity of the swing spring is an S-shaped cavity, and the S-shaped cavity is surrounded by a pair of S-shaped side plates arranged with equal spacing.

[0007] Preferably, the damping material is nitrile rubber, and the hardness of nitrile rubber is 30-90HA; the two S-shaped side plates of the swing spring have equal thickness, which is 0.5-1.5mm; the bearing outer ring, tilting pad and swing spring are an integrated structure, and the bearing outer ring, tilting pad and swing spring are all made of 40CrMo alloy.

[0008] Preferably, the symmetry plane of a pair of swing springs in each damping structure has a deviation angle of ≤5° along the symmetry plane of the tilting pad connected thereto passing through the central axis, and the deviation directions of the symmetry planes of the swing springs in the four damping structures are consistent, that is, the deviation directions of the swing springs are uniformly counterclockwise or clockwise, and the deviation angles are the same.

[0009] Preferably, at least three capillary flow holes are provided in each of the pressure equalizing grooves, and the outlet end of each capillary flow hole is chamfered and arranged in a trumpet shape; the capillary flow hole is connected to the air inlet hole on the tilting pad at a 90° angle.

[0010] Preferably, when the air inlet holes of four tilting pads are respectively connected to four external air supply channels, two adjacent tilting pads are selected as bearing pads, and temperature measuring holes are set on one end face of each of them; when the air inlet holes on two adjacent tilting pads are connected in parallel to one external air supply channel, and the air inlet holes on the other two adjacent tilting pads are connected in parallel to the second external air supply channel, one group of two adjacent tilting pads sharing the same external air supply channel is selected as bearing pads, and temperature measuring holes are set on one end face of each of them.

[0011] A method for manufacturing the bearing as described above comprises the following steps: S1. Simulation design: Use simulation software to simulate various bearing parameters and select the optimal bearing parameters based on the expected bearing size and design requirements; S2. Cutting and forming: Based on the simulation data obtained in step S1, the bearing outer ring, the swing spring and the tilting pad are cut into an integrated form by wire cutting, and an S-shaped cavity is cut inside the swing spring; S3. Injecting the damping layer: injecting the rubber raw material in a fluid state into the S-shaped cavity, and completing vulcanization and curing under controlled temperature and pressure conditions to form a stably bonded S-shaped rubber elastomer.

[0012] The beneficial effects of the present invention are: The present invention adopts a sandwich damping structure, which consists of a damping layer sandwiched between two side plates of a swing spring. The overall structure is simple, the bearing size can be flexibly adjusted according to different working conditions, and the design is flexible and convenient. The damping layer material can be selected from different material types and performance specifications according to the specific working scenario and the load-bearing conditions of the tilting pad, so that the bearing can flexibly respond to different working conditions and design requirements and obtain the best vibration reduction performance. By effectively combining high-strength, high-toughness 40CrMo alloy steel with nitrile rubber with good elasticity and oil resistance, not only the bearing structure's load-bearing capacity and overall stability are enhanced, but also its vibration reduction and buffering characteristics are significantly improved. This multi-material collaborative design helps to improve the operating reliability and service life of the bearing system, and meet the comprehensive performance requirements for high-performance vibration reduction support components under complex working conditions.

[0013] The damping structure used in the present invention is stable and reliable. By adding a damping interlayer to the swing spring, the damping can be kept unchanged under the set working conditions, which greatly improves the vibration reduction performance and stability of the air flexible support tilting pad bearing. In combination with the four sets of asymmetrically positioned swing springs and tilting pads, the tolerance of the bearing to misalignment and imbalance can be improved, and the anti-interference ability of the bearing can be further improved. The elastic modulus of the nitrile rubber used is much smaller than that of the alloy steel used in the bearing, so filling the damping material will not affect the equivalent stiffness of the bearing.

[0014] Compared with the existing air flexible support tilting pad bearing, the present invention adopts a design without end covers, which not only helps to improve the heat dissipation performance of the damping layer in the swing spring, but also facilitates the connection between the air inlet holes on the four tilting pads and the external air supply channel, and the structure is simpler and more flexible. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a front view of Example 1 of the present invention; Figure 2 Schematic diagram of the inner side structure of the tilting pad in Example 1 of the present invention; Figure 3 Schematic diagram of the three-dimensional structure of Example 1 of the present invention; Figure 4 : This is a time domain diagram of the bearing acceleration signal under three different rubber hardnesses in Example 3 of the present invention; Figure 5 This is a flow chart of the manufacturing method in Example 4 of the present invention; Figure 6 Schematic diagram of the three-dimensional structure of a quarter bearing used for simulation testing in Example 4 of the present invention; Figure 7 Graph showing the frequency domain amplitude of displacement signals of a conventional bearing and a bearing of the present application in Example 5 of the present invention; Figure 8 This is a time domain diagram of the acceleration signal of the existing bearing in Example 5 of the present invention and the bearing of the present application.

[0016] In the figure: bearing outer ring 1; damping layer 2; tilting pad 3; swing spring 4; air inlet 5; temperature measuring hole 6; pressure equalizing groove 7; capillary flow hole 8. DETAILED DESCRIPTION

[0017] Example 1 The following is a further explanation of the present invention with reference to specific embodiments. Figure 1-3 As shown, this embodiment is an air-flexibly supported tilting pad bearing with a sandwich damping structure, which mainly includes a circular bearing outer ring 1. Four tilting pads 3 are arranged on the inner side of the bearing outer ring 1. Each tilting pad 3 is connected to the bearing outer ring 1 through a damping structure. The four tilting pads 3 have the same opening angle, a clearance fit between each other, and are all pre-eccentric.

[0018] Each damping structure includes a pair of swing springs 4, which are respectively arranged at the outer ends of the tilting pad 3. Each pair of swing springs 4 is asymmetrically arranged along the symmetry plane of the tilting pad connected to it through the central axis, with a deviation angle of ≤5°. The deviation direction of the symmetry plane of the swing springs 4 of the four tilting pads 3 is consistent, that is, the deviation direction of the swing springs 4 is uniformly counterclockwise or clockwise, and the deviation angle is the same. This arrangement is more conducive to forming a wedge-shaped dynamic pressure film between the rotor shaft and the tilting pad 3.

[0019] The swing spring 4 has an S-shaped structure and is composed of two S-shaped side plates with equal spacing. The gap between the two S-shaped side plates constitutes an S-shaped cavity, which is filled with damping material to form a damping layer 2 sandwiched inside the swing spring 4; the damping layer 2 can swing with different filling materials according to the specific working scenario of the bearing and the load-bearing conditions of the tilting pad 4. In this embodiment, the damping layer 2 selects nitrile rubber with a Shore hardness of 50HA as the damping material filling; and the bearing outer ring 1, the swing spring 4 and the tilting pad 3 are made of 40CrMo alloy steel cut in one piece. Compared with other parts of the bearing, the elastic modulus of the damping layer 2 is much smaller than that of alloy steel, so it will not affect the equivalent stiffness of the bearing.

[0020] An air inlet hole 5 is provided on the end face of each tilting pad 3. The air inlet hole 5 is located at the center of the end face of the tilting pad 3 (the center of the air inlet hole 5 is located on the symmetric plane of the tilting pad 3 passing through the central axis); a pressure equalizing groove 7 is provided on the inner side face of each tilting pad 3 (the side close to the central axis of the bearing outer ring). Figure 3 As shown; three capillary flow holes 8 are provided on the inner side of the pressure equalizing tank 7, and the capillary flow holes 8 are connected to the air inlet hole 5 and connected to the air inlet hole 5 at 90 degrees; it can ensure that the air supply in the pressure equalizing tank 7 is sufficient, so that the pressure drop of the gas from the air compressor to the pressure equalizing tank 7 is reduced; the chamfer at the outlet of the capillary flow hole 8 is set in a trumpet shape to reduce the influence of the air hammer effect; there are three capillary flow holes 8, which can make the gas pressure at each place in the pressure equalizing tank 7 close to the same.

[0021] The pressure-bearing side of the two tilting pads 3 arranged at the lower side are both provided with temperature measuring holes 6 for cooperating with probes of temperature sensors to detect the temperature of the tilting pads 3 .

[0022] In actual use of this embodiment, air is supplied to the bearing through an external air supply pipe connected to the air inlet 5. Each tilting pad 3 is supplied with air independently, or the load-bearing pads or non-load-bearing pads are grouped in pairs for air supply. The air supply volume of each tilting pad 3 can be monitored in real time and controlled separately to achieve multiple air supply methods, including: compressed air with the same gas pressure passing through four pads, atmospheric pressure through the non-load-bearing pads, compressed air through the load-bearing pads, and compressed air with different gas pressures passing through the non-load-bearing pads and the load-bearing pads; the load-bearing pads are the two lower tilting pads 3, and the non-load-bearing pads are the two upper tilting pads 3.

[0023] During bearing operation, due to external loading and the rotor's own weight, the two lower tilting pads 3 bear the load, and the damping layer 2 is compressed and deformed, providing flexible support for the rotor and preventing rigid contact. They also absorb some mechanical energy and convert it into internal energy, thereby playing a damping and vibration suppression role. The two upper tilting pads 3 act as non-load-bearing pads. During normal bearing operation, the upper pads are slightly stretched due to shearing, and the damping layer 2 also deforms accordingly. In high-frequency vibrations, the hysteresis characteristics of the rubber can also provide additional damping and vibration isolation, preventing structural resonance. During the starting and stopping stages of the bearing, gas is introduced into the pressure-equalizing groove 7 on the tilting pad 3 through the air inlet 5 to play a role in static pressure bearing. At this time, the air film is fully controllable, so that the pressure and air film thickness in the bearing gap are in a stable and unchanged state, ensuring that the bearing can generate a lubricating air film at low speeds during the starting and stopping stages to reduce wear. During the high-speed operation of the bearing, the tilting pad structure in this embodiment can further enhance the fluid dynamic pressure effect, form a dynamic pressure air film in the bearing gap, and thus support the bearing to further improve the bearing capacity.

[0024] The size of the pressure equalizing groove 7 can be designed and adjusted according to application needs; when the bearing runs at high speed, a dynamic pressure air film is formed in the bearing gap, and the pressure equalizing groove 7 will have a certain impact on the dynamic pressure air film; if the focus is on the application of dynamic pressure bearings, the air supply of the pressure equalizing groove 7 will be removed after the dynamic pressure air film is formed, and the load is only carried by the dynamic pressure air film. At this time, the role of the pressure equalizing groove 7 is to reduce the wear between the bearing and the rotor under low speed conditions. Therefore, the size of the pressure equalizing groove 7 can be appropriately reduced to reduce the impact of the pressure equalizing groove 7 on the dynamic pressure air film under high speed conditions; on the contrary, if the focus is on the application of static pressure bearings, the air supply to the pressure equalizing groove 7 is maintained after the dynamic pressure air film is formed, and the dynamic pressure effect and static pressure are used to carry the load. In this case, the bearing seat is mainly carried by static pressure, and the area of the pressure equalizing groove 7 can be appropriately increased to improve the bearing capacity of the bearing.

[0025] Example 2 The difference between this embodiment and embodiment 1 is that the damping material used in the damping layer 2 of this embodiment is nitrile rubber with a Shore hardness of 70HA.

[0026] Example 3 The difference between this embodiment and embodiment 2 is that the damping material used in the damping layer 2 of this embodiment is nitrile rubber with a Shore hardness of 90HA.

[0027] The hardness of the damping layer 2 determines the damping performance of the bearing. Rubber with higher hardness deforms less when subjected to force and has greater rigidity, which can provide stronger structural support. However, its ability to dissipate energy is limited, and the damping effect is relatively weak. Rubber with lower hardness has greater deformation capacity and better energy absorption performance, which is beneficial to improving the damping capacity of the structure, but may lead to insufficient support stiffness, thereby affecting the load-bearing stability of the bearing.

[0028] like Figure 4 As shown, Figure 4 The acceleration signal time domain diagrams of the damping layer 2 under three different rubber hardnesses, among which (a) is 50HA, (b) is 70HA, and (c) is 90HA. It can be seen from the figure that with the increase of rubber hardness, the acceleration signal amplitude also increases; due to the high hardness of 90HA rubber, the shear strain is insufficient, and the vibration energy is more easily transmitted through the rigid structure rather than dissipated, and the vibration reduction effect is weakened. The 50HA rubber has a relatively low stiffness and allows a larger shear strain, thereby fully stimulating the energy dissipation capacity of the viscoelastic material. Its flexible properties can effectively absorb high-frequency vibration energy, suppress vibration transmission, and reduce vibration amplitude. The acceleration amplitude of 70HA rubber is between the two; through simulation of nitrile rubbers of different hardnesses, it is found that the damping layer 2 of different hardnesses has little effect on the equivalent stiffness of the bearing. Therefore, the appropriate damping material hardness can be freely selected according to specific usage requirements.

[0029] Example 4 This embodiment is a method for manufacturing an air-flexible support tilting pad bearing with a sandwich damping structure. Figure 5 As shown, the following steps are included: S1. Simulation design: Use simulation software to simulate various bearing parameters and select the optimal bearing parameters based on the expected bearing size and design requirements.

[0030] In this embodiment, ANSYS finite element simulation software is used to simulate the Figure 6A static analysis of the 1 / 4 bearing structure shown in the figure was performed. By observing the deformation of the bearing under applied load and the corresponding stiffness value, the thickness of the side plate of the swing spring 4 was determined. Simulation results show that the thickness of the swing spring 4 has a significant impact on the stiffness and deformation of the bearing structure. When the swing spring 4 thickness is small, the bearing deformation increases and the stiffness decreases; conversely, the stiffness increases but the deformation is small. To ensure that the bearing has a certain damping performance while also providing sufficient support stiffness and appropriate deformation, the bearing structure described in Example 1 is used in this embodiment with a bearing inner diameter of 30 mm, an outer diameter of 90 mm, a bearing width of 25 mm, and a bearing shell thickness of 5 mm. Using ANSYS software, simulations and comparisons of different swing spring 4 thicknesses revealed that a swing spring thickness of 0.7 mm on both sides has the optimal support stiffness and deformation. ANSYS simulations can be used to compare and analyze the effects of different swing spring 4 thicknesses on the bearing structure stiffness and deformation for different bearing sizes and design requirements, thereby selecting the optimal swing spring thickness.

[0031] S2. Cutting and forming: Based on the simulation data obtained in step S1, the bearing outer ring 1, the swing spring 4, and the tilting pad 3 are integrally cut by wire cutting, and an S-shaped cavity is cut inside the swing spring. In this embodiment, the bearing outer ring 1, the swing spring 4, and the tilting pad 3 are integrally cut by wire cutting using 40CrMo alloy steel, which has excellent mechanical properties. Its high yield strength and tensile strength can effectively withstand the high loads during operation.

[0032] S3. Inject the damping layer; inject the rubber raw material in a fluid state into the S-shaped cavity, and complete vulcanization and curing under controlled temperature and pressure conditions to form a stably bonded S-shaped rubber elastomer; this production method has a simple manufacturing process and low cost, and can not only improve the bonding reliability between the damping layer 2 and the swing spring 4, but also ensure the durability, elasticity and strength of the damping layer 2.

[0033] By effectively combining high-strength, high-toughness 40CrMo alloy steel with nitrile rubber, which exhibits excellent elasticity and oil resistance, the bearing structure not only enhances its load-bearing capacity and overall stability, but also significantly improves its vibration damping and cushioning properties. This multi-material collaborative design helps improve the operating reliability and service life of the bearing system, meeting the comprehensive performance requirements of high-performance vibration damping support components under complex operating conditions.

[0034] Example 5 In this embodiment, in order to verify the performance of the air flexible support tilting pad bearing with a sandwich damping structure in Example 1, an existing double-layer spring air flexible support tilting pad bearing is selected for comparative experimental analysis; Figure 7 and Figure 8As shown, the displacement signal frequency domain amplitude and acceleration signal time domain diagram of the two springs are respectively when the upper pad air supply is 0.05MPa, the lower pad air supply is 0.1MPa, and the rotation speed is 7000r / min, where (a) is the existing double-layer spring bearing and (b) is the sandwich damping bearing in this application.

[0035] Depend on Figure 7 It can be seen that the dual-spring bearing structure has a maximum displacement amplitude of approximately 0.035 mm at a frequency of 115 Hz; while the maximum displacement amplitude of the sandwich damping bearing structure in Example 1 is approximately 0.025 mm. The results show that compared with the dual-spring bearing structure, the supporting capacity of the sandwich damping bearing structure in Example 1 is improved, and the system vibration response is smoother.

[0036] Depend on Figure 8 It can be seen that the sandwich damping bearing structure in the present application exhibits better vibration reduction effect and can effectively suppress vibration; while the existing double-layer spring bearing structure has more acceleration signal spikes, more violent vibrations, and a significant instantaneous impact on the rotor system.

[0037] In summary, the air-flexible-support tilting pad bearing with a sandwich damping structure in Example 1 of the present application has better vibration damping performance and smaller vibration energy and impact than the existing air-flexible-support tilting pad bearing, can significantly improve the stability of the bearing-rotor system, and exhibits a good operating state.

[0038] The above description is merely a further explanation of the present invention in conjunction with specific embodiments. All descriptions do not limit the scope of protection of the present invention. Any changes or replacements that can be easily thought of by any technician in this field within the technical scope disclosed by the present invention should be included in the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. An air-flexible tilting pad bearing with a sandwich damping structure, comprising a bearing outer ring with four tilting pads evenly distributed on the inner side of the bearing outer ring, characterized in that: Each of the tilting pads is connected to the inner ring of the bearing via a damping structure, and each of the damping structures includes a pair of swing springs; the swing spring is a sandwich structure with a cavity inside, and the cavity is filled with damping material to form a damping layer; the opening angle of each of the tilting pads is the same, and they are arranged with clearance fit with each other; a pressure equalizing groove is provided on the side of the tilting pad close to the central axis of the outer ring of the bearing, and an air inlet is provided on the end face of the tilting pad; the air inlet holes of the four tilting pads are respectively connected to four external air supply channels, or: the air inlet holes on two adjacent tilting pads are connected in parallel to one external air supply channel, and the air inlet holes on the other two adjacent tilting pads are connected in parallel to the second external air supply channel.

2. The air-flexible support tilting pad bearing with a sandwich damping structure according to claim 1, characterized in that: The swing spring has an S-shaped structure, and the two ends of the swing spring are fixedly connected to the inner side surface of the bearing outer ring and the outer side surface of the tilting pad respectively; the internal cavity of the swing spring is an S-shaped cavity, and the S-shaped cavity is surrounded by a pair of S-shaped side plates set at equal intervals.

3. The air-flexible support tilting pad bearing with a sandwich damping structure according to claim 2, characterized in that: The damping material is nitrile rubber, and the hardness of nitrile rubber is 30-90HA; the two S-shaped side plates of the swing spring have equal thickness, which is 0.5-1.5mm; the bearing outer ring, tilting pad and swing spring are an integrated structure, and the bearing outer ring, tilting pad and swing spring are all made of 40CrMo alloy.

4. The air-flexible support tilting pad bearing with a sandwich damping structure according to claim 1, characterized in that: The symmetry plane of a pair of swing springs in each damping structure has a deviation angle of ≤5° along the symmetry plane of the tilting pad connected to it passing through the central axis, and the deviation direction of the symmetry plane of the swing springs in the four damping structures is consistent, that is, the deviation direction of the swing springs is uniformly counterclockwise or clockwise, and the deviation angle is the same.

5. The air-flexible support tilting pad bearing with a sandwich damping structure according to claim 1, characterized in that: Each of the pressure equalizing grooves is provided with at least three capillary flow holes, and the outlet end of each capillary flow hole is chamfered and arranged in a trumpet shape; the capillary flow hole is connected to the air inlet hole on the tilting pad at a 90° angle.

6. The air-flexible tilting pad bearing with a sandwich damping structure according to claim 1, characterized in that: When the air inlet holes of four tilting pads are respectively connected to four external air supply channels, two adjacent tilting pads are selected as bearing pads, and temperature measuring holes are set on one end face of each of them; when the air inlet holes on two adjacent tilting pads are connected in parallel to one external air supply channel, and the air inlet holes on the other two adjacent tilting pads are connected in parallel to the second external air supply channel, one group of two adjacent tilting pads sharing the same external air supply channel is selected as bearing pads, and temperature measuring holes are set on one end face of each of them.

7. A method for manufacturing a bearing according to claims 1 to 6, comprising the following steps: S1. Simulation design: Use simulation software to simulate various bearing parameters and select the optimal bearing parameters based on the expected bearing size and design requirements; S2. Cutting and forming: Based on the simulation data obtained in step S1, the bearing outer ring, the swing spring and the tilting pad are cut into an integrated form by wire cutting, and an S-shaped cavity is cut inside the swing spring; S3. Injecting the damping layer: injecting the rubber raw material in a fluid state into the S-shaped cavity, and completing vulcanization and curing under controlled temperature and pressure conditions to form a stably bonded S-shaped rubber elastomer.

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