Self-lubricating gaskets and their preparation methods, self-lubricating bearings and their preparation methods

Abstract

This invention discloses a self-lubricating gasket and its preparation method, as well as a self-lubricating bearing and its preparation method, relating to the field of self-lubricating bearing technology. The self-lubricating gasket preparation method includes: immersing a fabric in a first impregnation solution containing phenolic resin, allowing the phenolic resin to penetrate into the fiber bundles of the fabric, resulting in a fabric with phenolic resin adhering to it; semi-curing the fabric with phenolic resin adhering to it to obtain a first-stage semi-cured fabric; sealing and protecting the bonding surface of the first-stage semi-cured fabric; repeatedly pouring a second impregnation solution containing phenolic resin and nanoparticles onto the friction surface of the first-stage semi-cured fabric, and repeatedly pressing the friction surface of the fabric using an extrusion plate to allow the second impregnation solution to fully penetrate into the fiber bundles; and semi-curing the fabric impregnated with the second impregnation solution to obtain a self-lubricating gasket. This method achieves modification through nanoparticle filling while preventing nanoparticles from adhering to the bonding surface of the fabric gasket, resulting in good adhesion performance and service life.

Description

Technical Field

[0001] This invention relates to the field of self-lubricating bearing technology, and particularly to a self-lubricating gasket and its preparation method, and a self-lubricating bearing and its preparation method. Background Technology

[0002] Fabric gaskets, woven from a mixture of polytetrafluoroethylene (PTFE) fibers and reinforcing fibers, impregnated with phenolic resin, and then cured, exhibit excellent self-lubricating properties when used in self-lubricating spherical plain bearings. To further enhance the performance and lifespan of spherical plain bearings under harsh environments, researchers modified the impregnating resin with microparticle filling, achieving significant friction-reducing and wear-resistant effects. The modified gasket was bonded to the inner surface of the outer ring with phenolic resin, and after curing at 180°C by clamping a sleeve around the outer ring, a single-slot spherical plain bearing was obtained.

[0003] Modifying the gasket by filling it with impregnating resin is currently the mainstream approach. However, research has almost exclusively focused on the tribological properties of the modified gasket, with limited attention paid to the fiber bundle bonding of the modified gasket and its adhesion to the bearing outer ring during application. In fact, in bearing applications, the adhesion between the gasket fiber bundles and between the gasket and the bearing outer ring significantly impacts the bearing's service life. Heavy-load tests show that failure due to poor adhesion between the gasket and the outer ring often precedes gasket wear failure.

[0004] Existing methods for preparing gaskets primarily involve impregnating fabric with resin, followed by degumming and semi-curing under pressure. While resin modified with microparticles improves the tribological properties of the gasket to some extent, these microparticles inevitably deteriorate the resin's adhesive properties, reducing the binding force between fabric fiber bundles and consequently lowering bonding performance. Furthermore, existing impregnation methods leave a large number of microparticles on the gasket bonding surface. The presence of these microparticles severely affects the adhesion between the gasket and the bearing outer ring, making the gasket prone to detachment under harsh environments. Additionally, single-slot spherical plain bearings typically employ traditional external clamping during manufacturing, which cannot maintain sufficient pressure, also leading to reduced peel strength.

[0005] It is evident that existing technologies still need improvement and enhancement. Summary of the Invention

[0006] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a self-lubricating gasket and its preparation method, and a self-lubricating bearing and its preparation method, in order to solve the defect that the existing micro-particle filled modified gasket has insufficient adhesion performance, resulting in a decrease in service life.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] A method for preparing a self-lubricating gasket, wherein the method includes:

[0009] The fabric is immersed in a first impregnation solution containing phenolic resin, allowing the phenolic resin to penetrate into the fiber bundles of the fabric, resulting in a fabric with phenolic resin attached.

[0010] The fabric with phenolic resin attached is semi-cured to obtain a semi-cured fabric.

[0011] Seal and protect the bonding surface of the semi-cured fabric;

[0012] The second impregnation liquid containing phenolic resin and nanoparticles is repeatedly poured onto the friction surface of the first semi-cured fabric, and the friction surface of the fabric is repeatedly squeezed by the extrusion plate to allow the second impregnation liquid to fully penetrate into the fiber bundle.

[0013] The fabric impregnated with the second impregnation solution is semi-cured to obtain a self-lubricating pad.

[0014] In the method for preparing the self-lubricating gasket, the first impregnation solution further includes a diluent, wherein the amount of diluent added to the first impregnation solution is 30% to 40% of the weight of the phenolic resin.

[0015] In the self-lubricating gasket preparation method, the amount of nanoparticles added to the second impregnation solution is 5% to 10% of the weight of the phenolic resin.

[0016] In the self-lubricating gasket preparation method described above, the nanoparticles include one of nano-silica, graphite, and alumina.

[0017] In the method for preparing the self-lubricating gasket, the second impregnation liquid further includes a diluent, and the amount of the diluent added is 20% to 25% of the weight of the phenolic resin.

[0018] In the self-lubricating gasket preparation method, the conditions for the semi-curing step are: temperature of 90-95℃, pressure of 0.8-1MPa, and semi-curing time of 60-70min.

[0019] A self-lubricating gasket, wherein the self-lubricating gasket is prepared by the self-lubricating gasket preparation method described above.

[0020] A self-lubricating bearing includes an outer ring, an inner ring, and a gasket disposed between the outer ring and the inner ring, wherein the gasket is a self-lubricating gasket as described above.

[0021] A method for preparing a self-lubricating bearing, comprising: applying phenolic resin to the bonding surface of a self-lubricating liner and attaching it to the inner surface of an outer ring; inserting a PTFE buffer ring into the outer ring; clamping the outer ring with a sleeve until the gap is closed; inserting an expansion sleeve into the PTFE buffer ring and expanding it, then curing it for 2 hours; after curing, removing the expansion sleeve, the PTFE buffer ring, and the sleeve, and inserting them into the inner ring to obtain a self-lubricating bearing.

[0022] In the self-lubricating bearing preparation method described above, the curing temperature is 170–180°C.

[0023] Beneficial effects:

[0024] This invention provides a method for preparing a self-lubricating gasket. The method involves two impregnation processes, and before the second impregnation, the bonding surface of the semi-cured fabric is sealed. This achieves the goal of modifying the fabric with nanoparticles while preventing nanoparticles from adhering to the bonding surface of the fabric gasket. As a result, the bonding surface of the prepared self-lubricating gasket is free of nanoparticles. Therefore, when the self-lubricating gasket is bonded to the inner surface of the outer ring of the bearing, it has good adhesion performance, making it less prone to falling off and resulting in a longer service life.

[0025] The present invention also provides a method for preparing a self-lubricating bearing. This method significantly increases the bonding and curing pressure of the bearing by internal pressure curing, thereby ensuring that the gasket and the outer ring have high peel strength, are not prone to falling off during use, and have a longer service life. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the structure of the self-lubricating bearing provided by the present invention.

[0027] Figure 2 This is a structural diagram of the clamp, outer ring, bushing, PTFE buffer ring, and expansion sleeve.

[0028] Figure 3 The images show the friction and bonding surfaces of the self-lubricating gasket (in the figures, (a) shows the friction surface and (b) shows the bonding surface).

[0029] Figure 4 The images show physical examples and comparative examples after the liner has been peeled off during the peel strength test.

[0030] Figure 5 Figures are physical images of each embodiment and comparative example after service performance testing (where (1) is of embodiment 1, (2) is of comparative example 2, and (3) is of comparative example 3).

[0031] The markings in the attached diagram are: 1-outer ring, 2-inner ring, 3-shield, 4-PTFE buffer ring, 5-hoop, 6-expansion sleeve. Detailed Implementation

[0032] This invention provides a self-lubricating gasket and its preparation method, as well as a self-lubricating bearing and its preparation method. To make the objectives, technical solutions, and effects of this invention clearer and more explicit, the following embodiments are provided to further illustrate the invention in detail. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of the invention.

[0033] To improve the friction and wear performance of fabric gaskets, existing fabric gaskets are typically modified using microparticle filling during preparation. However, this leads to a decrease in the adhesion between the fabric fiber bundles and the gasket and the bearing, resulting in a reduction in the service life of the gasket. To address the problem of reduced bearing service life caused by microparticle filling modification in existing technologies, the first aspect of this invention provides a method for preparing a self-lubricating gasket, the method comprising:

[0034] Single impregnation: The fabric is immersed in a first impregnation solution containing phenolic resin, allowing the phenolic resin to penetrate into the fiber bundles of the fabric, resulting in a fabric impregnated with phenolic resin.

[0035] One-time semi-curing: The fabric impregnated with phenolic resin is semi-cured to obtain a one-time semi-cured fabric.

[0036] Sealing and protection: Sealing and protecting the bonding surface of the semi-cured fabric;

[0037] Secondary impregnation: The second impregnation liquid containing phenolic resin and nanoparticles is repeatedly poured onto the friction surface of the primary semi-cured fabric, and the friction surface of the primary semi-cured fabric is repeatedly squeezed during the pouring process to allow the secondary impregnation liquid to fully penetrate into the fiber bundles.

[0038] Secondary semi-curing: The fabric impregnated with the second impregnation liquid is semi-cured to obtain a self-lubricating pad.

[0039] In this embodiment, the first impregnation step uses a diluted phenolic resin solution. Through impregnation, phenolic resin can penetrate the fabric and fiber bundles. Since the first impregnation solution does not contain nanoparticles, pure phenolic resin can be left in the fiber bundles after the semi-curing step. Pure phenolic resin has good adhesive properties, so the fiber bundles can be bonded together and are not easy to fall apart during subsequent use, resulting in a longer service life. It can also improve the bonding strength between the bonding surface and the bearing. It should be noted that the fabric is a blend of polytetrafluoroethylene (PTFE) fibers and reinforcing fibers; the first semi-curing process partially cures the phenolic resin, resulting in a semi-cured resin with adhesive properties that prevents the fiber bundles from detaching. Simultaneously, the semi-cured resin imparts softness to the fabric, facilitating subsequent steps. Furthermore, the semi-curing process evaporates the solvent from the first impregnation solution, creating pores within the fabric that allow the phenolic resin and nanoparticles to penetrate during the subsequent second impregnation. The sealing protection seals the adhesive surfaces of the first semi-cured fabric, for example, by attaching adhesive release paper to the adhesive surfaces, thus sealing them. Therefore, during the second impregnation, the nanoparticle-containing second impregnation... The liquid can only penetrate from the friction surface of the semi-cured fabric, thus preventing nanoparticles from adhering to the bonding surface of the fabric and causing a decrease in bonding strength. This ensures that the bonding strength between the gasket and the inner surface of the bearing outer ring is not affected by the nanoparticles. The secondary impregnation, through repeated pouring of the secondary impregnation liquid and squeezing of the fabric friction surface, allows the secondary impregnation liquid to penetrate well into the pores of the fabric. At the same time, since the secondary impregnation liquid contains phenolic resin and nanoparticles, the phenolic resin can further improve the binding effect of each fiber bundle in the fabric and also improve the tribological properties of the gasket. The secondary semi-curing process partially cures the phenolic resin that has penetrated into the fabric through the secondary impregnation, so that the prepared self-lubricating gasket maintains good flexibility and is easy to attach to the bearing.

[0040] In this embodiment, by using a double impregnation method, and by sealing the bonding surface of the semi-cured fabric before the second impregnation, it is possible to achieve modification through nanoparticle filling while preventing nanoparticles from adhering to the bonding surface of the fabric pad. This results in a self-lubricating pad with a bonding surface free of nanoparticles (specifically, as shown in the example). Figure 3 As shown in the figure, when the self-lubricating gasket is bonded to the inner surface of the outer ring of the bearing, it has good adhesion performance, making the self-lubricating gasket less likely to fall off and having a longer service life.

[0041] In the above preparation method, the first impregnation liquid is a diluted phenolic resin solution, which is composed of phenolic resin and a diluent. The concentration of the phenolic resin affects its binding force between fiber bundles and the number of pores formed after semi-curing. When the concentration of phenolic resin is high, it can increase the binding force between fiber bundles, but it reduces the number of pores formed within the fabric. This makes it difficult for phenolic resin and nanoparticles to penetrate during the second impregnation, leading to a decrease in frictional performance. Therefore, in a preferred embodiment, the diluent added to the first impregnation liquid is 30% to 40% of the weight of the phenolic resin. This allows for the formation of a larger number of pores, facilitating the penetration of phenolic resin and nanoparticles in the second impregnation liquid. Simultaneously, this mass ratio of phenolic resin results in stronger binding forces within the fabric and between fiber bundles, making it less prone to disintegration during use, thus giving the prepared self-lubricating pad a longer service life.

[0042] In the secondary impregnation, the amount of nanoparticles added in the second impregnation solution affects the tribological properties of the self-lubricating pad and the bonding strength of the phenolic resin. In order to improve the tribological properties of the self-lubricating pad and at the same time make the phenolic resin have good bonding strength, in a preferred embodiment, the amount of nanoparticles added is 5% to 10% of the weight of the phenolic resin.

[0043] In some embodiments, the nanoparticles include one of nano-silica, graphite, and alumina, all of which are nanoscale particles that can improve the tribological properties of the pad and have the functions of reducing friction and resisting wear.

[0044] In a preferred embodiment, the secondary impregnation solution further includes a diluent, the amount of which is 20% to 25% of the weight of the phenolic resin. Compared with the first impregnation solution, the amount of diluent added in the second impregnation solution is less, thereby increasing the concentration of the phenolic resin, making the phenolic resin more binding to the fiber bundles in the fabric, and improving the bonding strength.

[0045] In the above preparation method, the phenolic resin penetrated into the fabric through two semi-curing processes is semi-cured. During semi-curing, the phenolic resin is rapidly semi-cured by heating and pressurizing. In a preferred embodiment, the semi-curing conditions are: temperature 90-95°C, pressure 0.8-1 MPa, and semi-curing time 60-70 min. Under these conditions, the phenolic resin is only partially cured, thus possessing certain adhesive properties, which can bond fiber bundles together. At the same time, because the phenolic resin is only partially cured, the fabric remains flexible, facilitating the subsequent bonding of the liner to the bearing. This allows for better adhesion to the inner surface of the outer ring, resulting in a more stable bond and preventing detachment during use.

[0046] In a preferred embodiment, a fabric cleaning step is provided before the initial impregnation. This step includes immersing the fabric in anhydrous ethanol / acetone solution and sonicating for 1 hour, followed by drying in a 60°C oven. Ultrasonic cleaning removes impurities from the fabric, preventing these impurities from affecting the adhesive properties of the padding.

[0047] A second aspect of this invention also provides a self-lubricating gasket, which is prepared by the self-lubricating gasket preparation method described above. The adhesive surface of the self-lubricating gasket is used to bond to the inner surface of the outer ring of the bearing, and its friction surface is used to contact the inner ring. The adhesive surface of this self-lubricating gasket is sealed and protected before secondary impregnation, thus avoiding contact with nanoparticles and leaving no nanoparticle residue. Therefore, when bonded to the inner surface of the outer ring with phenolic resin, it has strong peel strength and will not easily detach under harsh environments. Simultaneously, the friction surface of this self-lubricating gasket, modified with nanoparticles, has good tribological properties. Therefore, this self-lubricating gasket combines the friction-reducing and anti-wear effects of modified resin with the strong bonding and adhesive properties of pure phenolic resin, resulting in a long service life when applied to bearings.

[0048] A third aspect of the present invention also provides a self-lubricating bearing, such as... Figure 1 As shown, the self-lubricating bearing includes an outer ring 1, an inner ring 2, and a gasket 3 disposed between the outer ring and the inner ring, wherein the gasket is a self-lubricating gasket as described above. This self-lubricating bearing exhibits good frictional performance. Service performance tests revealed that after 25,000 cycles at 240 MPa, a frequency of 0.2 Hz, and an amplitude of ±5°, the wear amount was only 0.06–0.07 mm, and the gasket surface remained intact, with the fiber bundles in the gasket not detaching or failing. Therefore, this self-lubricating bearing has a long service life.

[0049] The fourth aspect of this invention also provides a method for preparing a self-lubricating bearing, the method comprising: coating the adhesive surface of a self-lubricating gasket 3 with phenolic resin and attaching it to the inner surface of an outer ring 1; inserting a PTFE buffer ring 4 into the outer ring 1; fitting a clamping sleeve 5 onto the outer ring and clamping the sleeve until the gap is closed, and locking it; inserting an expansion sleeve 6 into the PTFE buffer ring and expanding it (at this time the result is as follows). Figure 2 As shown in the figure, when the expansion is complete and the self-lubricating liner is tightly fitted to the outer ring, heat and cure for 2 hours; after curing, remove the expansion sleeve 6, PTFE buffer ring 4 and hoop, and install the inner ring 2 to obtain the self-lubricating bearing.

[0050] In this embodiment, the PTFE buffer ring has a ring structure, with its side surface in contact with the friction surface of the gasket. The inner PTFE ring has a certain degree of elasticity, allowing it to expand outwards elastically when subjected to an external force in a radially outward direction. The expansion sleeve can expand outwards, compressing the PTFE buffer ring, which in turn compresses the gasket, causing the gasket to adhere tightly to the inner surface of the outer ring. Therefore, through the action of the PTFE buffer ring and the expansion sleeve, the gasket can be compressed from the inside, resulting in better adhesion and stronger bonding to the inner surface of the outer ring. Compared to existing methods that rely solely on a clamping mechanism, this embodiment provides a significantly stronger bond between the gasket and the outer ring.

[0051] In a preferred embodiment, the temperature for heat curing the gasket is 170–180°C, which allows the phenolic resin to cure better and faster, and ensures that the gasket is firmly bonded to the substrate.

[0052] To further illustrate the self-lubricating gasket preparation method, self-lubricating gasket, self-lubricating bearing and preparation method provided by the present invention, the following embodiments are provided.

[0053] Example 1

[0054] A method for preparing a self-lubricating gasket includes: immersing a fabric in anhydrous ethanol / acetone and sonicating it for 1 hour, then drying it in a 60°C oven for later use; taking a first impregnation solution in which the mass ratio of ethyl acetate, ethanol, and phenolic resin is 1:1:5, immersing the fabric in the first impregnation solution for 30 minutes, removing it, removing excess resin from the fabric surface with a scraper, and semi-curing it at 90°C and 0.8 MPa for 60 minutes to obtain a semi-cured fabric; and then applying adhesive release paper to the bonding surface of the semi-cured fabric. After sealing and protection, a second impregnation liquid is repeatedly poured onto the friction surface of the semi-cured fabric. By weight, the second impregnation liquid consists of 10 parts ethyl acetate, 10 parts ethanol, 100 parts phenolic resin, and 6 parts silica. During the pouring of the second impregnation liquid, the fabric friction surface is continuously rolled and squeezed by an extrusion plate to ensure that the second impregnation liquid fully penetrates the fabric. After the fabric has fully absorbed the second impregnation liquid, excess resin on the fabric surface is removed by a scraper. The fabric is then semi-cured for 60 minutes at 90°C and 0.8 MPa to obtain a self-lubricating pad.

[0055] The self-lubricating pad prepared in Example 1 was used to prepare a self-lubricating bearing. The preparation method of the self-lubricating bearing is as follows: the adhesive surface of the self-lubricating pad is coated with phenolic resin and then bonded to the inner surface of the outer ring of the bearing. A PTFE buffer ring of suitable size is installed in the outer ring. A hoop is put on the outer ring and the hoop is clamped to close the gap. An expansion sleeve is placed in the PTFE buffer ring and expanded so that the self-lubricating pad is tightly attached to the inner surface of the outer ring. Then it is cured at 180°C for two hours. The expansion sleeve is removed, the hoop is loosened, the inner PTFE buffer ring is removed and installed in the inner ring to obtain the self-lubricating bearing.

[0056] Example 2

[0057] A method for preparing a self-lubricating gasket includes: immersing a fabric in anhydrous ethanol / acetone and sonicating it for 1 hour, then drying it in a 60°C oven for later use; taking a first impregnation solution in which the mass ratio of ethyl acetate, ethanol, and phenolic resin is 1.5:1.5:10, immersing the fabric in the first impregnation solution for 30 minutes, removing it, removing excess resin from the fabric surface with a scraper, and then semi-curing it at 95°C and 1.0 MPa for 65 minutes to obtain a one-time semi-cured fabric; and then applying a coating to the bonding surface of the one-time semi-cured fabric. After the release paper is used for sealing and protection, a second impregnation liquid is repeatedly poured onto the friction surface of the semi-cured fabric. By weight, the second impregnation liquid consists of 10 parts ethyl acetate, 10 parts ethanol, 80 parts phenolic resin, and 4 parts graphite. During the pouring of the second impregnation liquid, the extrusion plate continuously rolls and presses the fabric friction surface to ensure that the second impregnation liquid fully penetrates the fabric. After the fabric has fully absorbed the second impregnation liquid, excess resin on the fabric surface is removed by a scraper. The fabric is then semi-cured at 95°C and 1.0 MPa for 65 minutes to obtain a self-lubricating pad.

[0058] The self-lubricating gasket prepared in Example 2 was used to prepare a self-lubricating bearing. The preparation method was basically the same as that in Example 1, except that the curing temperature was 170°C.

[0059] Example 3

[0060] A method for preparing a self-lubricating gasket includes: immersing a fabric in anhydrous ethanol / acetone and sonicating it for 1 hour, then drying it in a 60°C oven for later use; taking a first impregnation solution in which the mass ratio of ethyl acetate, ethanol, and phenolic resin is 1:1:5.54, immersing the fabric in the first impregnation solution for 30 minutes, removing it, removing excess resin from the fabric surface with a scraper, and semi-curing it at 92°C and 0.9 MPa for 70 minutes to obtain a one-time semi-cured fabric; and applying an adhesive release liner to the bonding surface of the one-time semi-cured fabric. After the paper is sealed and protected, a second impregnation liquid is repeatedly poured onto the friction surface of the semi-cured fabric. By weight, the second impregnation liquid consists of 10 parts ethyl acetate, 10 parts ethanol, 90 parts phenolic resin, and 9 parts alumina. During the pouring of the second impregnation liquid, the extrusion plate continuously rolls and presses the fabric friction surface to allow the second impregnation liquid to fully penetrate the fabric. After the fabric has fully absorbed the second impregnation liquid, the excess resin on the fabric surface is removed by a scraper, and the fabric is semi-cured for 70 minutes at 92°C and 0.9 MPa to obtain a self-lubricating pad.

[0061] The self-lubricating gasket prepared in Example 3 was used to prepare a self-lubricating bearing. The preparation method of the self-lubricating bearing was basically the same as that in Example 1, except that the curing temperature was 175°C.

[0062] Comparative Example 1

[0063] A method for preparing a self-lubricating bearing includes the following steps: The fabric is immersed in anhydrous ethanol / acetone and sonicated for 1 hour, then dried in an oven at 60°C for later use. A mixing solution is prepared by weight of 10 parts ethyl acetate, 10 parts ethanol, 100 parts phenolic resin, and 6 parts silica. The fabric is placed in an impregnation device, and the mixing solution is poured onto the friction surface of the fabric. The impregnation solution is then continuously pressed and rolled on the friction surface by an extrusion plate to ensure it penetrates deeply into the fibers. After the fabric has fully absorbed the mixing solution, excess resin is removed from the fabric surface by a scraper. The fabric is then semi-cured at 90°C and 0.8 MPa for 60 minutes to obtain a liner.

[0064] Bearing bonding and curing: The bonding surface of the gasket prepared in Comparative Example 1 was coated with phenolic resin and then bonded to the outer ring of the bearing. The outer ring was clamped with a hoop until the gap was closed, and the bearing was obtained by curing at 180°C for two hours.

[0065] Comparative Example 2

[0066] The self-lubricating gasket prepared in Example 1 was used to prepare a bearing. The bearing was prepared by applying phenolic resin to the bonding surface of the gasket and then bonding it to the outer ring of the bearing. The outer ring was clamped with a hoop until the gap was closed, and then cured at 180°C for two hours to obtain the bearing.

[0067] Comparative Example 3

[0068] A method for preparing a pad includes: immersing a fabric in anhydrous ethanol / acetone and sonicating it for 1 hour, then drying it in an oven at 60°C for later use; pouring an impregnation solution onto the surface of the cleaned fabric, and continuously pressing and squeezing the fabric's friction surface with an extrusion plate to ensure the impregnation solution fully penetrates the fibers; the impregnation solution, by weight, consists of 10 parts ethyl acetate, 10 parts ethanol, 100 parts phenolic resin, and 6 parts silica; after the fabric has fully absorbed the impregnation solution, removing excess resin from the fabric surface with a scraper, and then semi-curing it at 90°C and 0.8 MPa for 60 minutes to obtain the pad.

[0069] The gasket prepared in Comparative Example 3 was used to prepare a bearing. The bearing was prepared by applying phenolic resin to the bonding surface of the gasket and then bonding it to the outer ring of the bearing. A PTFE buffer ring of the corresponding size was then inserted, and the outer ring was clamped with a sleeve until the gap was closed. An expansion sleeve was placed in the PTFE buffer ring and expanded. Then, it was cured at 180°C for two hours. The expansion sleeve was removed, the sleeve was loosened, the inner PTFE buffer ring was removed, and then it was inserted into the inner ring to obtain the bearing.

[0070] The bearings prepared in Examples 1-3 and Comparative Examples 1-3 were subjected to peel strength and service performance tests. The peel strength test was conducted according to the AS81820 standard. The service performance test involved 25,000 oscillations under conditions of 240 MPa pressure, 0.2 Hz oscillation frequency, and ±5° oscillation amplitude. After the test, the wear of the gasket was measured, and the surface morphology of the gasket was observed. Specific test results are shown in Table 1.

[0071] Table 1. Performance Test Results

[0072]

[0073]

[0074] As shown in Table 1, the self-lubricating gaskets prepared in Examples 1-3 exhibit higher peel strength, which is two to three times that of comparative examples 1-3. This demonstrates that the preparation methods for the self-lubricating gaskets and self-lubricating bearings described in this invention can significantly improve the bonding strength of the gaskets. Furthermore, as... Figure 4 As shown, the gaskets described in Examples 1-3 retain their complete morphology after peeling, exhibiting strong binding forces between surface fiber bundles and are not easily damaged. In contrast, the gaskets described in Comparative Examples 1-3 all exhibited varying degrees of unbonded areas after peeling, primarily due to insufficient adhesive performance and curing pressure.

[0075] As can be seen from the wear data in Table 1, the wear of the pads described in Examples 1-3 is significantly lower than that of Comparative Examples 1-3, and their surfaces remain intact after the wear test. Figure 5As shown, the pads prepared by this invention have excellent tribological properties. However, the wear amounts of Comparative Examples 1-3 were all above 0.1 mm, and there were instances of pad tearing and fiber bundle separation, indicating insufficient wear resistance, possibly due to inadequate adhesion.

[0076] In summary, the self-lubricating gasket preparation method of the present invention produces a gasket with good adhesive strength and tribological properties, which can avoid the shortened service life caused by insufficient adhesive strength of the gasket, and therefore has better application prospects.

[0077] It is understood that those skilled in the art can make equivalent substitutions or modifications to the technical solution and inventive concept of the present invention, and all such substitutions or modifications should fall within the protection scope of the appended claims.

Claims

1. A method for preparing a self-lubricating gasket, characterized in that, The method includes: The fabric is immersed in a first impregnation solution containing phenolic resin, allowing the phenolic resin to penetrate into the fiber bundles of the fabric, resulting in a fabric with phenolic resin attached. The fabric with phenolic resin attached is semi-cured to obtain a semi-cured fabric. Seal and protect the bonding surface of the semi-cured fabric; The second impregnation liquid containing phenolic resin and nanoparticles is repeatedly poured onto the friction surface of the first semi-cured fabric, and the friction surface of the fabric is repeatedly squeezed by the extrusion plate to allow the second impregnation liquid to fully penetrate into the fiber bundle. The fabric impregnated with the second impregnation solution is semi-cured to obtain a self-lubricating pad.

2. The method for preparing a self-lubricating gasket according to claim 1, characterized in that, The first impregnation solution also includes a diluent, the amount of which is 30% to 40% of the weight of the phenolic resin.

3. The method for preparing a self-lubricating gasket according to claim 1, characterized in that, In the second impregnation solution, the amount of nanoparticles added is 5% to 10% of the weight of the phenolic resin.

4. The method for preparing a self-lubricating gasket according to claim 3, characterized in that, The nanoparticles include one of nano-silica, graphite, and alumina.

5. The method for preparing a self-lubricating gasket according to claim 1, characterized in that, The second impregnation solution also includes a diluent, the amount of which is 20% to 25% of the weight of the phenolic resin.

6. The method for preparing a self-lubricating gasket according to claim 1, characterized in that, The conditions for the semi-curing step are: temperature of 90-95℃, pressure of 0.8-1MPa, and semi-curing time of 60-70min.

7. A self-lubricating gasket, characterized in that, The self-lubricating gasket is prepared by the self-lubricating gasket preparation method according to any one of claims 1-6.

8. A self-lubricating bearing, characterized in that, It includes an outer ring, an inner ring, and a gasket disposed between the outer ring and the inner ring, wherein the gasket is a self-lubricating gasket as described in claim 7.

9. A method for preparing a self-lubricating bearing as described in claim 8, characterized in that, The method includes: applying phenolic resin to the bonding surface of the self-lubricating liner and attaching it to the inner surface of the outer ring; inserting a PTFE buffer ring into the outer ring; clamping the outer ring with a sleeve until the gap is closed; inserting an expansion sleeve into the PTFE buffer ring and expanding it, then curing it for 2 hours; after curing, removing the expansion sleeve, PTFE buffer ring, and sleeve, and installing them into the inner ring to obtain a self-lubricating bearing.

10. The method for preparing a self-lubricating bearing according to claim 9, characterized in that, The curing temperature is 170–180℃.

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