Machining process of bearing cage

Abstract

This application relates to the field of bearing component processing, specifically disclosing a processing technology for a bearing cage, including the following steps: 1) degreasing and cleaning; 2) sandblasting; 3) electrostatic spraying; 4) pre-baking; 5) sintering and curing; 6) cleaning. This application employs a process of sandblasting the cage surface, followed by spraying a slurry, and finally sintering and curing. During spraying, the slurry penetrates into the microscopic pits formed by the sandblasting of the cage. After sintering and curing, the copper powder in the slurry undergoes atomic interdiffusion with the steel substrate surface, forming a diffusion layer to achieve metal bonding. The pore-forming agent decomposes and escapes during sintering, forming a three-dimensional interconnected pore network in situ. Simultaneously, the copper powder sintersties into a stable metal skeleton. After vacuum impregnation, the base lubricating oil is stored in the pores through capillary action. During bearing operation, frictional heat and centrifugal force drive the base oil in the pores to continuously and slowly seep out, replenishing the main grease in small amounts, compensating for the performance degradation caused by the loss of base oil, and extending the effective service life of the grease.

Description

Technical Field

[0001] This application relates to the field of bearing component processing, and more specifically, it relates to a processing technology for a bearing cage. Background Technology

[0002] As the core transmission component of mechanical equipment, the core function of bearings is to support the rotating body of the machine, reduce frictional resistance during movement, and ensure rotational accuracy. To achieve this function, lubrication is a key aspect of bearing design and use, and the reliability of bearing lubrication directly determines the operational stability and service life of the equipment.

[0003] In related technologies, the main processing steps of bearings include: turning, heat treatment, and grinding of the raceways (inner and outer rings); manufacturing of the rolling elements (steel balls or rollers); forming and processing of the cage; and finally, cleaning, assembling, clearance adjustment, grease injection, and sealing (or adding a dust cover) of the bearing. Among these, the grease injection process is usually carried out in the final assembly stage, where a specified type and amount of grease is filled into the raceway and cage space of the bearing using specialized equipment.

[0004] However, under complex working conditions such as long-term operation, high speed, high temperature, or heavy load, pre-filled grease will gradually undergo failure phenomena such as oxidation, oil separation, evaporation, contamination, and loss of base oil. This leads to a reduction in effective grease, increased friction and wear, and a shortened effective service life of the grease. Users must regularly stop the machine for maintenance and frequently replenish or replace the grease, which needs to be improved. Summary of the Invention

[0005] To address the issue of shortened effective service life of grease in bearings, this application provides a manufacturing process for a bearing cage.

[0006] The processing technology for a bearing cage provided in this application adopts the following technical solution:

[0007] A manufacturing process for a bearing cage includes the following steps:

[0008] 1) Degreasing and cleaning: Immerse the cage in an alkaline water-based cleaning agent with a concentration of 3-5% at 60-70℃ for ultrasonic degreasing for 5-8 minutes, then ultrasonically rinse in deionized water for 4-6 minutes, and finally immerse in a water-based dehydrating rust inhibitor for 1-2 minutes, and then dry at 80-100℃.

[0009] 2) Sandblasting: Use quartz sand to sandblast the surface of the cage to be coated under a pressure of 0.4-0.6MPa. After sandblasting, perform ultrasonic cleaning and then dry at 80-100℃.

[0010] 3) Electrostatic spraying: In a 30-40kV high-voltage electrostatic field, the slurry is sprayed onto the surface of the cage to be coated. The slurry is prepared by mixing a mixture of copper powder and pore-forming agent in a mass ratio of 7:3 with a binder solution in a liquid-solid ratio of 1:3.

[0011] 4) Pre-baking: Bake the coated cage at 80-120℃ for 10-30 minutes;

[0012] 5) Sintering and curing: The cage is sent into the sintering furnace, and a nitrogen-hydrogen mixture of 95% N2 + 5% H2 is introduced to raise the temperature to 300-400℃ at 2-5℃ / min and hold for 30-60min. Then the temperature is raised to 750-850℃ at 8-15℃ / min and held for 60-120min. The furnace is then cooled to room temperature under the protective gas.

[0013] 6) Cleaning: The sintered cage is ultrasonically cleaned and dried. The cage is then immersed in lubricating base oil at 80°C and kept under a vacuum of <0.1 bar for 30 minutes. After that, it is restored to normal pressure and soaked for 2 hours. The cage is then removed and left to stand at 80°C for 30-60 minutes to drain.

[0014] By adopting the above technical solution, the slurry penetrates into the micro-pits formed by sandblasting on the surface of the cage during spraying. After sintering and curing, the copper powder in the slurry undergoes atomic interdiffusion with the steel substrate surface of the cage, forming a diffusion layer at the interface and achieving metal bonding. Meanwhile, the pore-forming agent in the slurry decomposes and escapes during sintering, leaving a three-dimensional interconnected pore network corresponding to the original particle morphology in situ. At the same time, the copper powder forms a stable metal skeleton after sintering. After vacuum impregnation, the skeleton stores the base lubricating oil in the pores through capillary action. During bearing operation, the base lubricating oil stored in the pores is continuously and slowly seeped out to the friction interface through capillary action under the drive of frictional heat and centrifugal force, realizing a micro-replenishment of the main grease. This effectively compensates for the performance degradation of the main grease caused by the loss of base oil and extends the effective service life of the grease.

[0015] Preferably, in step 6), the sintered retainer is placed in a vacuum chemical vapor deposition furnace, MoS2 gas is introduced at 280-320°C, and deposition is carried out at a pressure of 300Pa for 20-30 minutes. Then the sintered retainer is ultrasonically cleaned.

[0016] By adopting the above technical solution, a nanoscale molybdenum disulfide film is generated on the surface of the cage through chemical vapor deposition. The molybdenum disulfide film has extremely low shear strength, which can provide solid lubrication when the bearing encounters extreme conditions such as instantaneous high temperature causing grease loss or temporary depletion of grease after long-term operation. This reduces the risk of bearing failure due to untimely maintenance, reduces frictional loss of grease, reduces frictional heat generation, and slows down the oxidative decomposition of grease, thereby helping to extend the effective service life of grease on the bearing.

[0017] Preferably, in step 3), the copper powder comprises spherical fine copper powder and irregular coarse copper powder in a mass ratio of 4:6, wherein the particle size of the spherical fine copper powder is 15-25 μm and the particle size of the irregular coarse copper powder is 60-80 μm.

[0018] By adopting the above technical solution, fine copper powder fills the gaps between coarse copper powder, which increases the packing density of the slurry coating, improves the macroscopic strength of the metal skeleton, and reduces the sintering shrinkage rate. The pores of coarse copper powder serve as the main channels for lubricating oil, facilitating lubricating oil penetration. The secondary pores formed by the filling of fine copper powder provide capillary force for storing lubricating oil, thus achieving the optimal balance between oil storage and oil delivery.

[0019] Preferably, the pore-forming agent is urea.

[0020] By adopting the above technical solution, the decomposition products of urea are small molecule gases such as NH3, CO2, and H2O, without producing any solid or liquid residues. It is green and environmentally friendly. Urea is completely decomposed and vaporized at 300-400℃. At this time, the metal particles have not yet begun to sinter and bond. The skeleton will not be severely deformed due to gas escape. During subsequent high-temperature sintering, since the metal skeleton has been pre-arranged tightly, the sintering shrinkage mainly occurs at the contact points between particles, rather than overall densification. Therefore, the overall linear shrinkage rate can be controlled, ensuring the dimensional accuracy of the cage and avoiding coating cracking or deformation caused by uneven shrinkage.

[0021] Preferably, the adhesive solution is a 5-6% aqueous solution of polyvinyl alcohol.

[0022] By adopting the above technical solution, polyvinyl alcohol is soluble in water and is completely compatible with urea, which can form a uniform and stable slurry. The flexibility provided by the high molecular chain of polyvinyl alcohol can buffer the stress generated by temperature changes and organic decomposition in the early stage of sintering, and reduce the tendency to crack.

[0023] Preferably, the ultrasonic cleaning step involves immersing the cage in a deionized water solution containing 1% neutral surfactant, performing ultrasonic cleaning at 45°C for 5-8 minutes, then transferring it to a flowing deionized water tank for ultrasonic rinsing at room temperature for 3 minutes, and finally transferring it to a static deionized water tank for ultrasonic rinsing for 2 minutes.

[0024] By adopting the above technical solution, the surface of the cage can be thoroughly cleaned, avoiding the risk of failure such as blistering and premature peeling of the slurry coating caused by residual abrasive, oil or salt.

[0025] In summary, this application has the following beneficial effects:

[0026] 1. Because this application adopts the method of first sandblasting the surface of the cage, then spraying the slurry, and finally sintering and curing, the slurry penetrates into the micro-pits formed by the sandblasting of the cage during spraying. After sintering and curing, the copper powder in the slurry undergoes atomic interdiffusion with the surface of the steel substrate to form a diffusion layer and achieve metal bonding. The pore-forming agent decomposes and escapes during sintering, forming a three-dimensional interconnected pore network in situ. At the same time, the copper powder is sintered into a stable metal skeleton. After vacuum impregnation, the lubricating base oil is stored in the pores through capillary action. When the bearing is running, the frictional heat and centrifugal force drive the base oil in the pores to continuously and slowly seep out, replenishing the main grease in a small amount, compensating for the performance degradation caused by the loss of base oil, and extending the effective service life of the grease.

[0027] 2. A nanoscale molybdenum disulfide film is generated on the cage surface by chemical vapor deposition. The molybdenum disulfide film has extremely low shear strength. When the bearing encounters extreme conditions such as instantaneous high temperature causing grease loss or temporary depletion of grease after long-term operation, it can provide solid lubrication, reduce the risk of bearing failure due to untimely maintenance, reduce frictional loss of grease, reduce frictional heat generation, and thus slow down the oxidative decomposition of grease, thereby helping to extend the effective service life of grease on the bearing.

[0028] 3. This application uses a mixture of fine copper powder and coarse copper powder. The fine copper powder fills the gaps between the coarse copper powder, which increases the packing density of the slurry coating, improves the macroscopic strength of the metal skeleton, and reduces the sintering shrinkage rate. The pores of the coarse copper powder serve as the main channels for lubricating oil, facilitating the penetration of lubricating oil. The secondary pores formed by the filling of fine copper powder provide capillary force for storing lubricating oil, thus achieving the optimal balance between oil storage and oil delivery. Detailed Implementation

[0029] The present application will be further described in detail below with reference to the embodiments.

[0030] information alkaline water-based cleaning agent Model: MLJ-3384L Cleaning Agent Water-based dehydrating rust inhibitor Model: Cortec VpCI-649 Lubricating base oil PAO 4 base oil Polyvinyl alcohol Degree of alcoholysis 87-89%, degree of polymerization 500-1800 neutral surfactants Alkylphenol polyoxyethylene ether Quartz sand Particle size: 16-60 mesh, Mohs hardness: 7.0±0.2

[0031] Unless otherwise specified, all raw materials used in the following embodiments are commercially available.

[0032] Preparation Example 1

[0033] The slurry is prepared as follows: irregular coarse copper powder and pore-forming agent with a mass ratio of 7:3 are weighed and mixed at 300 r / min for 6-8 min to obtain a mixture. The particle size of the irregular coarse copper powder is 60-80 μm, and the pore-forming agent is urea. While maintaining a speed of 300 r / min and stirring, a binder solution is added dropwise to the mixture. After each dropwise addition, the mixture is stirred for 2-3 min. The binder solution is a 5% polyvinyl alcohol aqueous solution, and the liquid-solid ratio of the binder solution to the mixture is 1:3. After the dropwise addition is completed, the speed is increased to 800 r / min and stirred for 20-30 min. Then, the mixture is transferred to a vacuum chamber and vacuumed (0.08–0.1 MPa) for degassing for 3-5 min.

[0034] Preparation Example 2

[0035] The slurry is prepared as follows: irregular coarse copper powder and pore-forming agent with a mass ratio of 7:3 are weighed and mixed at a speed of 300 r / min for 6-8 min to obtain a mixture. The particle size of the irregular coarse copper powder is 60-80 μm, and the pore-forming agent is urea. While maintaining a speed of 300 r / min and stirring, a binder solution is added dropwise to the above mixture. After each dropwise addition, the mixture is stirred for 2-3 min. The binder solution is a 6% polyvinyl alcohol aqueous solution, and the liquid-solid ratio of the binder solution to the mixture is 1:3. After the dropwise addition is completed, the speed is increased to 800 r / min and stirred for 20-30 min. Then, the mixture is transferred to a vacuum chamber and vacuumed (0.08–0.1 MPa) for degassing for 3-5 min.

[0036] Preparation Example 3

[0037] The preparation method of the slurry is as follows: Weigh out spherical fine copper powder and irregular coarse copper powder in a mass ratio of 4:6 and mix them evenly to obtain copper powder. The particle size of the spherical fine copper powder is 15-25μm and the particle size of the irregular coarse copper powder is 60-80μm. Then weigh out copper powder and pore-forming agent in a mass ratio of 7:3 and mix them at a speed of 300r / min for 6-8min to obtain a mixture. The pore-forming agent is urea. While maintaining a speed of 300r / min and stirring, add the binder solution dropwise to the above mixture. Stir for 2-3min after each drop. The binder solution is a 5% polyvinyl alcohol aqueous solution. The liquid-solid ratio of the binder solution to the mixture is 1:3. After the dropwise addition is completed, increase the speed to 800r / min and stir for 20-30min. Then transfer it to a vacuum chamber and degas (0.08–0.1MPa) for 3-5min.

[0038] Example 1

[0039] This application discloses a method for preparing an antibacterial filter cloth, comprising the following steps:

[0040] 1) Degreasing and cleaning: Immerse the cage in a 3% alkaline water-based cleaning agent at 60℃ for ultrasonic degreasing for 8 minutes, then ultrasonically rinse in deionized water for 4 minutes, finally immerse in a water-based dehydrating rust inhibitor for 1 minute, and then dry at 80℃.

[0041] 2) Sandblasting: The surface of the cage to be coated is sandblasted with quartz sand at a pressure of 0.4 MPa. After sandblasting, ultrasonic cleaning is performed. The ultrasonic cleaning steps are as follows: the cage is immersed in a deionized water solution containing 1% neutral surfactant and ultrasonically cleaned at 45°C for 5 minutes. Then it is transferred to a flowing deionized water tank and ultrasonically rinsed at room temperature for 3 minutes. Then it is transferred to a static deionized water tank and ultrasonically rinsed for 2 minutes. Finally, it is dried at 80°C.

[0042] 3) Electrostatic spraying: In a 30kV high-voltage electrostatic field, the slurry is sprayed onto the surface of the cage to be coated. The slurry is prepared in Preparation Example 1.

[0043] 4) Pre-baking: Bake the coated cage at 80℃ for 30 minutes;

[0044] 5) Sintering and curing: The cage is sent into the sintering furnace, and a nitrogen-hydrogen mixture of 95% N2 + 5% H2 is introduced to raise the temperature to 300°C at 2°C / min and hold for 60 min. Then the temperature is raised to 750°C at 8°C / min and held for 20 min. The furnace is then cooled to room temperature under the protective gas.

[0045] 6) Cleaning: The sintered cage is ultrasonically cleaned. The ultrasonic cleaning steps are as follows: the cage is immersed in a deionized water solution containing 1% neutral surfactant and ultrasonically cleaned at 45°C for 5 minutes. Then it is transferred to a flowing deionized water tank and ultrasonically rinsed at room temperature for 3 minutes. Then it is transferred to a static deionized water tank and ultrasonically rinsed for 2 minutes. After drying, the cage is immersed in lubricating base oil at 80°C and kept under a vacuum of <0.1 bar for 30 minutes. Then it is restored to normal pressure and soaked for 2 hours. After that, it is taken out and left to stand at 80°C for 30 minutes to drain.

[0046] Example 2

[0047] This application discloses a method for preparing an antibacterial filter cloth, comprising the following steps:

[0048] 1) Degreasing and cleaning: Immerse the cage in a 5% alkaline water-based cleaning agent at 70℃ for ultrasonic degreasing for 5 minutes, then ultrasonically rinse in deionized water for 6 minutes, finally immerse in a water-based dehydrating rust inhibitor for 2 minutes, and then dry at 100℃.

[0049] 2) Sandblasting: The surface of the cage to be coated is sandblasted with quartz sand at a pressure of 0.6 MPa. After sandblasting, ultrasonic cleaning is performed. The ultrasonic cleaning steps are as follows: the cage is immersed in a deionized water solution containing 1% neutral surfactant and ultrasonically cleaned at 45°C for 8 minutes. Then it is transferred to a flowing deionized water tank and ultrasonically rinsed at room temperature for 3 minutes. Then it is transferred to a static deionized water tank and ultrasonically rinsed for 2 minutes. Finally, it is dried at 100°C.

[0050] 3) Electrostatic spraying: In a 40kV high-voltage electrostatic field, the slurry is sprayed onto the surface of the cage to be coated. The slurry is obtained from Preparation Example 2.

[0051] 4) Pre-baking: Bake the coated retainer at 120℃ for 10 minutes;

[0052] 5) Sintering and curing: The cage is sent into the sintering furnace, and a nitrogen-hydrogen mixture of 95% N2 + 5% H2 is introduced to raise the temperature to 400°C at 5°C / min and hold for 30 min. Then the temperature is raised to 850°C at 15°C / min and held for 60 min. The furnace is then cooled to room temperature under the protective gas.

[0053] 6) Cleaning: The sintered cage is ultrasonically cleaned. The ultrasonic cleaning steps are as follows: the cage is immersed in a deionized water solution containing 1% neutral surfactant and ultrasonically cleaned at 45°C for 8 minutes. Then it is transferred to a flowing deionized water tank and ultrasonically rinsed at room temperature for 3 minutes. Then it is transferred to a static deionized water tank and ultrasonically rinsed for 2 minutes. After drying, the cage is immersed in lubricating base oil at 80°C and kept under a vacuum of <0.1 bar for 30 minutes. Then it is restored to normal pressure and soaked for 2 hours. Finally, it is taken out and left to stand at 80°C for 60 minutes to drain.

[0054] Example 3

[0055] This application discloses a method for preparing an antibacterial filter cloth, comprising the following steps:

[0056] 1) Degreasing and cleaning: Immerse the cage in a 4% alkaline water-based cleaning agent at 65℃ for ultrasonic degreasing for 7 minutes, then ultrasonically rinse in deionized water for 5 minutes, finally immerse in a water-based dehydrating rust inhibitor for 2 minutes, and then dry at 90℃.

[0057] 2) Sandblasting: The surface of the cage to be coated is sandblasted with quartz sand at a pressure of 0.5 MPa. After sandblasting, ultrasonic cleaning is performed. The ultrasonic cleaning steps are as follows: the cage is immersed in a deionized water solution containing 1% neutral surfactant and ultrasonically cleaned at 45°C for 7 minutes. Then it is transferred to a flowing deionized water tank and ultrasonically rinsed at room temperature for 3 minutes. Then it is transferred to a static deionized water tank and ultrasonically rinsed for 2 minutes. Finally, it is dried at 90°C.

[0058] 3) Electrostatic spraying: In a 35kV high-voltage electrostatic field, the slurry is sprayed onto the surface of the cage to be coated. The slurry is prepared in Preparation Example 1.

[0059] 4) Pre-baking: Bake the coated cage at 100℃ for 20 minutes;

[0060] 5) Sintering and curing: The cage is sent into the sintering furnace, and a nitrogen-hydrogen mixture of 95% N2 + 5% H2 is introduced to raise the temperature to 400°C at 4°C / min and hold for 45 min. Then the temperature is raised to 800°C at 10°C / min and held for 90 min. The furnace is then cooled to room temperature under the protective gas.

[0061] 6) Cleaning: The sintered cage is ultrasonically cleaned. The ultrasonic cleaning steps are as follows: the cage is immersed in a deionized water solution containing 1% neutral surfactant and ultrasonically cleaned at 45°C for 7 minutes. Then it is transferred to a flowing deionized water tank and ultrasonically rinsed at room temperature for 3 minutes. Then it is transferred to a static deionized water tank and ultrasonically rinsed for 2 minutes. After drying, the cage is immersed in lubricating base oil at 80°C and kept under a vacuum of <0.1 bar for 30 minutes. Then it is restored to normal pressure and soaked for 2 hours. After that, it is taken out and left to stand at 80°C for 45 minutes to drain.

[0062] Example 4

[0063] The difference from Example 1 is that in step 6), the sintered cage is placed in a vacuum chemical vapor deposition furnace, MoS2 gas is introduced at 280°C, and deposition is carried out at a pressure of 300Pa for 30 minutes. Then the sintered cage is ultrasonically cleaned.

[0064] It should be noted that, based on the above process parameters, the pores formed on the coating are at the micrometer level, and the nanoscale MoS2 thin film formed by chemical vapor deposition only covers the inner wall of the pores and does not block the pore channels.

[0065] Example 5

[0066] The difference from Example 1 is that the slurry was prepared by Preparation Example 3.

[0067] Example 6

[0068] 1) Degreasing and cleaning: Immerse the cage in a 3% alkaline water-based cleaning agent at 60℃ for ultrasonic degreasing for 8 minutes, then ultrasonically rinse in deionized water for 4 minutes, finally immerse in a water-based dehydrating rust inhibitor for 1 minute, and then dry at 80℃.

[0069] 2) Sandblasting: The surface of the cage to be coated is sandblasted with quartz sand at a pressure of 0.4 MPa. After sandblasting, ultrasonic cleaning is performed. The ultrasonic cleaning steps are as follows: the cage is immersed in a deionized water solution containing 1% neutral surfactant and ultrasonically cleaned at 45°C for 5 minutes. Then it is transferred to a flowing deionized water tank and ultrasonically rinsed at room temperature for 3 minutes. Then it is transferred to a static deionized water tank and ultrasonically rinsed for 2 minutes. Finally, it is dried at 80°C.

[0070] 3) Electrostatic spraying: In a 30kV high-voltage electrostatic field, the slurry is sprayed onto the surface of the cage to be coated. The slurry is prepared from Preparation Example 3.

[0071] 4) Pre-baking: Bake the coated cage at 80℃ for 30 minutes;

[0072] 5) Sintering and curing: The cage is sent into the sintering furnace, and a nitrogen-hydrogen mixture of 95% N2 + 5% H2 is introduced to raise the temperature to 300°C at 2°C / min and hold for 60 min. Then the temperature is raised to 750°C at 8°C / min and held for 20 min. The furnace is then cooled to room temperature under the protective gas.

[0073] 6) Cleaning: The sintered cage is placed in a vacuum chemical vapor deposition furnace, and MoS2 gas is introduced at 280°C. Deposition is carried out at a pressure of 300Pa for 30 minutes. Then, the sintered cage is ultrasonically cleaned. The ultrasonic cleaning steps are as follows: the cage is immersed in a deionized water solution containing 1% neutral surfactant and ultrasonically cleaned at 45°C for 5 minutes. Then, it is transferred to a flowing deionized water tank and ultrasonically rinsed at room temperature for 3 minutes. Then, it is transferred to a static deionized water tank and ultrasonically rinsed for 2 minutes. After drying, the cage is immersed in lubricating base oil at 80°C and kept under a vacuum of <0.1 bar for 30 minutes. Then, it is restored to normal pressure and soaked for 2 hours. Finally, it is taken out and left to stand at 80°C for 30 minutes to drain.

[0074] It should be noted that, based on the above process parameters, the pores formed on the coating are at the micrometer level, and the nanoscale MoS2 thin film formed by chemical vapor deposition only covers the inner wall of the pores and does not block the pore channels.

[0075] Example 7

[0076] This application discloses a method for preparing an antibacterial filter cloth, comprising the following steps:

[0077] 1) Degreasing and cleaning: Immerse the cage in a 5% alkaline water-based cleaning agent at 70℃ for ultrasonic degreasing for 5 minutes, then ultrasonically rinse in deionized water for 6 minutes, finally immerse in a water-based dehydrating rust inhibitor for 2 minutes, and then dry at 100℃.

[0078] 2) Sandblasting: The surface of the cage to be coated is sandblasted with quartz sand at a pressure of 0.6 MPa. After sandblasting, ultrasonic cleaning is performed. The ultrasonic cleaning steps are as follows: the cage is immersed in a deionized water solution containing 1% neutral surfactant and ultrasonically cleaned at 45°C for 8 minutes. Then it is transferred to a flowing deionized water tank and ultrasonically rinsed at room temperature for 3 minutes. Then it is transferred to a static deionized water tank and ultrasonically rinsed for 2 minutes. Finally, it is dried at 100°C.

[0079] 3) Electrostatic spraying: In a 40kV high-voltage electrostatic field, the slurry is sprayed onto the surface of the cage to be coated. The slurry is obtained from Preparation Example 3.

[0080] 4) Pre-baking: Bake the coated retainer at 120℃ for 10 minutes;

[0081] 5) Sintering and curing: The cage is sent into the sintering furnace, and a nitrogen-hydrogen mixture of 95% N2 + 5% H2 is introduced to raise the temperature to 400°C at 5°C / min and hold for 30 min. Then the temperature is raised to 850°C at 15°C / min and held for 60 min. The furnace is then cooled to room temperature under the protective gas.

[0082] 6) Cleaning: The sintered cage is placed in a vacuum chemical vapor deposition furnace, and MoS2 gas is introduced at 320°C. Deposition is carried out at a pressure of 300Pa for 20 minutes. Then, the sintered cage is ultrasonically cleaned. The ultrasonic cleaning steps are as follows: the cage is immersed in a deionized water solution containing 1% neutral surfactant and ultrasonically cleaned at 45°C for 8 minutes. Then, it is transferred to a flowing deionized water tank and ultrasonically rinsed at room temperature for 3 minutes. Then, it is transferred to a static deionized water tank and ultrasonically rinsed for 2 minutes. After drying, the cage is immersed in lubricating base oil at 80°C and kept under a vacuum of <0.1 bar for 30 minutes. Then, it is immersed at normal pressure for 2 hours. Finally, it is taken out and left to stand at 80°C for 60 minutes to drain.

[0083] It should be noted that, based on the above process parameters, the pores formed on the coating are at the micrometer level, and the nanoscale MoS2 thin film formed by chemical vapor deposition only covers the inner wall of the pores and does not block the pore channels.

[0084] Example 8

[0085] This application discloses a method for preparing an antibacterial filter cloth, comprising the following steps:

[0086] 1) Degreasing and cleaning: Immerse the cage in a 4% alkaline water-based cleaning agent at 65℃ for ultrasonic degreasing for 7 minutes, then ultrasonically rinse in deionized water for 5 minutes, finally immerse in a water-based dehydrating rust inhibitor for 2 minutes, and then dry at 90℃.

[0087] 2) Sandblasting: The surface of the cage to be coated is sandblasted with quartz sand at a pressure of 0.5 MPa. After sandblasting, ultrasonic cleaning is performed. The ultrasonic cleaning steps are as follows: the cage is immersed in a deionized water solution containing 1% neutral surfactant and ultrasonically cleaned at 45°C for 7 minutes. Then it is transferred to a flowing deionized water tank and ultrasonically rinsed at room temperature for 3 minutes. Then it is transferred to a static deionized water tank and ultrasonically rinsed for 2 minutes. Finally, it is dried at 90°C.

[0088] 3) Electrostatic spraying: In a 35kV high-voltage electrostatic field, the slurry is sprayed onto the surface of the cage to be coated. The slurry is prepared from Preparation Example 3.

[0089] 4) Pre-baking: Bake the coated cage at 100℃ for 20 minutes;

[0090] 5) Sintering and curing: The cage is sent into the sintering furnace, and a nitrogen-hydrogen mixture of 95% N2 + 5% H2 is introduced to raise the temperature to 400°C at 4°C / min and hold for 45 min. Then the temperature is raised to 800°C at 10°C / min and held for 90 min. The furnace is then cooled to room temperature under the protective gas.

[0091] 6) Cleaning: The sintered cage is placed in a vacuum chemical vapor deposition furnace, and MoS2 gas is introduced at 300°C. Deposition is carried out at 300Pa pressure for 25 minutes. Then, the sintered cage is ultrasonically cleaned. The ultrasonic cleaning steps are as follows: the cage is immersed in a deionized water solution containing 1% neutral surfactant and ultrasonically cleaned at 45°C for 7 minutes. Then, it is transferred to a flowing deionized water tank and ultrasonically rinsed at room temperature for 3 minutes. Then, it is transferred to a static deionized water tank and ultrasonically rinsed for 2 minutes. After drying, the cage is immersed in lubricating base oil at 80°C and kept under a vacuum of <0.1 bar for 30 minutes. Then, it is restored to normal pressure and soaked for 2 hours. Finally, it is taken out and left to stand at 80°C for 45 minutes to drain.

[0092] It should be noted that, based on the above process parameters, the pores formed on the coating are at the micrometer level, and the nanoscale MoS2 thin film formed by chemical vapor deposition only covers the inner wall of the pores and does not block the pore channels.

[0093] Comparative Example 1

[0094] The difference from Example 1 is that a cage that has not been processed in this application was used as a blank control group.

[0095] (1) Base oil slow release rate test: The oil-impregnated cages obtained in Examples 1-8 and Comparative Example 1 were placed in an 80℃ constant temperature oven (simulating the frictional heat of bearing operation). The mass loss of the cage was measured every 24 hours, and the base oil slow release rate was recorded. The test results are shown in Table 1 below.

[0096] (2) Lubricating grease performance degradation test: The cages of Examples 1-8 and Comparative Example 1 were respectively assembled onto bearings of the same model for testing. The bearing accelerated life test machine was used, with a speed of 5000 r / min, an ambient temperature of 80℃, and a radial load of 50% of the rated dynamic load. The machine was stopped and sampled every 200 hours until the lubricating grease was determined to be ineffective. The lubricating grease used was No. 2 general-purpose lithium-based grease, and the filling amount was 20% of the internal space of the bearing.

[0097] Sampling Procedure: After the bearing is shut down, wait for the temperature to drop to room temperature ±5℃. Clean the bearing end face with anhydrous ethanol. Use a syringe-type micro-sampler to extract grease samples from the gap between the bearing rolling elements and the cage. The sample size for each group should be ≥5g. Immediately after sampling, put the grease into a sealed sample bottle, label the group, sampling time, and cumulative running time, and store it at 4℃. After sampling, add an equal amount of new grease to the bearing to ensure that the total amount of grease is consistent in subsequent tests. Determine the acid value of the grease (characterizing the degree of oxidation and deterioration of the grease) according to the standard GB / T7304-2014 "Determination of Acid Value of Petroleum Products by Potentiometric Titration". When the increase in the acid value of the grease is >0.5mgKOH / g, record the cumulative running time at this time, which is the effective life of the bearing grease for that group. The test results are shown in Table 1 below.

[0098] Table 1 Performance Test Results

[0099] Base oil sustained-release rate (mg / day, 80℃) Cumulative running time (h) when the increase in acid value of lubricating grease is >0.5 mg KOH / g Example 1 18.2 1150 Example 2 16.8 1183 Example 3 17.5 1168 Example 4 16.5 1420 Example 5 12.5 1652 Example 6 11.8 1885 Example 7 11.6 1911 Example 8 12.0 1823 Comparative Example 1 / 845

[0100] In conclusion, the following conclusions can be drawn:

[0101] 1. As can be seen from Example 1 and Comparative Example 1, and Table 1, the bearing assembled with this cage can effectively extend the service life of the grease by performing a composite process of sandblasting pretreatment, specific slurry spraying, and sintering curing on the cage surface. The reason may be that: during spraying, the slurry penetrates into the micro-pits formed by the sandblasting of the cage. After sintering and curing, the copper powder in the slurry undergoes atomic interdiffusion with the surface of the steel substrate to form a diffusion layer and achieve metal bonding. The pore-forming agent decomposes and escapes during sintering, forming a three-dimensional interconnected pore network in situ. At the same time, the copper powder is sintered into a stable metal skeleton. After vacuum impregnation, the base oil is stored in the pores through capillary action. When the bearing is running, the frictional heat and centrifugal force drive the base oil in the pores to continuously and slowly seep out, replenishing the main grease in small amounts, compensating for the performance degradation caused by the loss of base oil, and extending the effective service life of the grease.

[0102] 2. As can be seen from Examples 1 and 4 and Table 1, the formation of a nano-scale molybdenum disulfide film on the cage surface by chemical vapor deposition is beneficial to extending the effective service life of the grease on the bearing equipped with the above-mentioned cage. The reason may be that the nano-scale molybdenum disulfide film formed on the cage surface by chemical vapor deposition has extremely low shear strength. When the bearing encounters extreme conditions such as instantaneous high temperature causing grease loss or temporary depletion of grease after long-term operation, it can provide solid lubrication, reduce the risk of bearing failure due to untimely maintenance, reduce frictional loss of grease, reduce the generation of frictional heat, and thus slow down the oxidative decomposition of grease, thereby helping to extend the effective service life of the grease on the bearing.

[0103] 3. Combining Examples 1 and 5 with Table 1, it can be seen that using mixed copper powders of different particle sizes can extend the effective service life of the grease on the bearing of the cage after assembly and processing. The reason may be that the pores of coarse copper powder serve as the main delivery channel for lubricating oil, which facilitates the penetration of lubricating oil. The secondary pores formed by the filling of fine copper powder provide capillary force for storing lubricating oil, thus achieving the optimal balance between oil storage and oil delivery.

[0104] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A manufacturing process for a bearing cage, characterized in that, Includes the following steps: 1) Degreasing and cleaning: Immerse the cage in an alkaline water-based cleaning agent with a concentration of 3-5% at 60-70℃ for ultrasonic degreasing for 5-8 minutes, then ultrasonically rinse in deionized water for 4-6 minutes, and finally immerse in a water-based dehydrating rust inhibitor for 1-2 minutes, and then dry at 80-100℃. 2) Sandblasting: Use quartz sand to sandblast the surface of the cage to be coated under a pressure of 0.4-0.6MPa. After sandblasting, perform ultrasonic cleaning and then dry at 80-100℃. 3) Electrostatic spraying: In a 30-40kV high-voltage electrostatic field, the slurry is sprayed onto the surface of the cage to be coated. The slurry is prepared by mixing a mixture of copper powder and pore-forming agent in a mass ratio of 7:3 with a binder solution in a liquid-solid ratio of 1:

3. 4) Pre-baking: Bake the coated cage at 80-120℃ for 10-30 minutes; 5) Sintering and curing: The cage is sent into the sintering furnace, and a nitrogen-hydrogen mixture of 95% N2 + 5% H2 is introduced to raise the temperature to 300-400℃ at 2-5℃ / min and hold for 30-60min. Then the temperature is raised to 750-850℃ at 8-15℃ / min and held for 60-120min. The furnace is then cooled to room temperature under the protective gas. 6) Cleaning: The sintered cage is ultrasonically cleaned and dried. The cage is then immersed in lubricating base oil at 80°C and kept under a vacuum of <0.1 bar for 30 minutes. After that, it is restored to normal pressure and soaked for 2 hours. The cage is then removed and left to stand at 80°C for 30-60 minutes to drain.

2. The processing technology of the bearing cage according to claim 1, characterized in that: In step 6), the sintered cage is placed in a vacuum chemical vapor deposition furnace, and MoS2 gas is introduced at 280-320°C. Deposition is carried out at a pressure of 300Pa for 20-30 minutes, and then the sintered cage is ultrasonically cleaned.

3. The processing technology of the bearing cage according to claim 1, characterized in that: In step 3), the copper powder includes spherical fine copper powder and irregular coarse copper powder in a mass ratio of 4:

6. The particle size of the spherical fine copper powder is 15-25 μm, and the particle size of the irregular coarse copper powder is 60-80 μm.

4. The processing technology of the bearing cage according to claim 3, characterized in that: The pore-forming agent is urea.

5. The processing technology of the bearing cage according to claim 3, characterized in that: The adhesive solution is a 5-6% aqueous solution of polyvinyl alcohol.

6. The processing technology of the bearing cage according to claim 1, characterized in that: The ultrasonic cleaning process involves immersing the cage in a deionized water solution containing 1% neutral surfactant, performing ultrasonic cleaning at 45°C for 5-8 minutes, then transferring it to a flowing deionized water tank for ultrasonic rinsing at room temperature for 3 minutes, and finally transferring it to a static deionized water tank for ultrasonic rinsing for 2 minutes.