Processing method of graphene solid lubrication bearing

Abstract

The invention discloses a processing method of a graphene solid lubrication bearing. The processing method comprises the following steps: providing a pre-assembled bearing original part; sacrificial material layers are formed on the surfaces of the retainer and the rolling body of the original bearing; graphite powder is die-cast between the outer ring and the inner ring of the original bearing to form a graphite module wrapping the retainer and the rolling body, and the graphite module is sintered and solidified; and the sacrificial material layer is removed, so that gaps are formed between the graphite module and the retainer as well as between the graphite module and the rolling body, and the graphene solid-state lubrication bearing is obtained. According to the processing method of the graphene solid lubrication bearing, the sacrificial material layer is firstly formed and then removed, so that gaps can be formed between the graphite module and the retainer as well as between the graphite module and the rolling body. Therefore, in the subsequent use of the bearing, friction extrusion between the graphite module and the retainer and the rolling body of the bearing can be avoided as much as possible, so that the self-lubricating effect and the service life of the graphene solid-state lubrication bearing are ensured.

Description

Technical Field

[0001] The invention belongs to the technical field of bearing manufacturing, and in particular relates to a processing method of a graphene solid-state lubrication bearing. Background Art

[0002] Graphite is a self-lubricating material. Graphene solid lubrication bearings are bearings made of graphite or graphite composite materials. They are gradually being used in the field of bearing manufacturing due to their excellent self-lubricating properties, high temperature tolerance and chemical stability. Such bearings are often used in high temperature environments, vacuum environments or environments that need to avoid lubricant contamination, where traditional lubricants are not suitable.

[0003] The graphene structure in the graphene solid lubrication bearing usually requires powder die-casting due to the special nature of its material to ensure the processing accuracy of the bearing. When the bearing produced by powder die-casting is in use, the graphene structure may produce a certain amount of friction and extrusion between the bearing cage and the rolling element, resulting in poor self-lubrication effect and short service life of the graphene solid lubrication bearing.

[0004] Therefore, in view of the above technical problems, it is necessary to provide a processing method for a graphene solid-state lubrication bearing. Summary of the invention

[0005] The purpose of the present invention is to provide a processing method for a graphene solid-lubricating bearing, which can solve the problem that the graphene structure may generate certain friction and extrusion between the bearing retaining frame and the rolling element, resulting in poor self-lubricating effect and short service life of the graphene solid-lubricating bearing.

[0006] In order to achieve the above object, a technical solution provided by a specific embodiment of the present invention is as follows:

[0007] A method for processing a graphene solid lubrication bearing comprises the following steps:

[0008] Provide pre-assembled bearing parts;

[0009] forming a sacrificial material layer on the surfaces of the retaining frame and the rolling element of the bearing original component;

[0010] Die-casting graphite powder between the outer ring and the inner ring of the bearing original component to form a graphite mold that wraps the retaining frame and the rolling body, and sintering and curing the graphite mold;

[0011] The sacrificial material layer is removed to form a gap between the graphite module and the retaining frame and the rolling element, thereby obtaining a graphene solid lubrication bearing.

[0012] In one or more embodiments of the present invention, removing the sacrificial material layer to form a gap between the graphite module and the retaining frame and the rolling element specifically includes:

[0013] The sintering and curing temperature of the graphite mold is controlled to liquefy or vaporize the sacrificial material layer.

[0014] In one or more embodiments of the present invention, sintering and curing the graphite module specifically includes:

[0015] Carrying out the first sintering of the graphite module;

[0016] Cooling the graphite module and the bearing original component, and performing polishing and milling on the end surfaces of the graphite module and the bearing original component;

[0017] The graphite mold is sintered a second time.

[0018] In one or more embodiments of the present invention, the first sintering temperature range of the graphite module is 200°C to 250°C, and the sintering time range is 1 to 1.5 hours; the second sintering temperature range of the graphite module is 350°C to 400°C, and the sintering time range is 2.5 to 3 hours.

[0019] In one or more embodiments of the present invention, a sacrificial material layer is formed on the surface of the retainer and the rolling element of the bearing original component, specifically comprising:

[0020] Place the bearing assembly in a prefabricated mold;

[0021] Injecting liquid sacrificial material into the mold to form a sacrificial material layer on the surface of the cage and rolling elements of the bearing original component;

[0022] After the sacrificial material layer is solidified, it is trimmed and excess sacrificial material and dust are removed.

[0023] In one or more embodiments of the present invention, the sacrificial material layer is paraffin.

[0024] In one or more embodiments of the present invention, after providing the pre-assembled bearing component, the following steps are further included:

[0025] The dirt and impurities on the surface of the bearing original part are removed by an automatic oil-water separation and filtration system of an ultrasonic cleaning device;

[0026] The bearing components are transported to a drying area to remove moisture from the surface and interior of the bearing components.

[0027] In one or more embodiments of the present invention, after the step of obtaining the graphene solid lubrication bearing, the following steps are also included:

[0028] The processed bearings are subjected to rotation torque test and surface visual test respectively, and good products are selected based on the test results;

[0029] Among them, when the rotational torque test result and the surface visual test result of the bearing both meet the requirements, the bearing is judged to be a good product; if either the rotational torque test result or the surface visual test result does not meet the requirements or both do not meet the requirements, the bearing is judged to be a defective product.

[0030] In one or more embodiments of the present invention, torque detection and visual detection are respectively performed on the processed bearings, and good products are screened out based on the detection results, specifically including:

[0031] Grab the bearing to the preset torque detection position, rotate the bearing and calculate its torque value;

[0032] Based on the comparison between the torque value and the preset torque value, determining whether the bearing is defective;

[0033] and / or, grabbing the bearing to a preset visual inspection position and acquiring an image of the bearing surface through a camera;

[0034] Performing denoising on the surface image based on a deep learning algorithm;

[0035] Based on whether there are defects or cracks in the surface image, it is determined whether the bearing is a defective product.

[0036] In one or more embodiments of the present invention, before the step of performing torque detection and visual detection on the processed bearings and selecting good products based on the detection results, the following steps are also included:

[0037] Clamp the bearing and drive the bearing to rotate so that the forward and reverse concentricity of the bearing is within the range of 0.03 to 0.05 or -0.05 to -0.03;

[0038] And / or, after performing torque detection and visual detection on the processed bearings respectively and selecting good products based on the detection results, the following steps are also included:

[0039] The bearings are coated with anti-rust paint inside and outside by spraying oil on the surface and filling oil inside.

[0040] Press the end cover onto one side of the bearing, turn the bearing over and then press the end cover onto the other side.

[0041] Compared with the prior art, in the processing method of the graphene solid lubrication bearing of the present invention, a sacrificial material layer is first formed on the surface of the bearing original component cage and the rolling element, then the graphite module is die-cast and sintered, and finally the sacrificial material layer is removed, so that a gap can be formed between the graphite module and the cage and the rolling element. Therefore, in the subsequent use of the bearing, due to the existence of the above-mentioned gap, friction and extrusion between the graphite module and the cage and the rolling element can be avoided as much as possible, thereby ensuring the self-lubricating effect and service life of the graphene solid lubrication bearing. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0043] Figure 1 is a process flow chart of a method for processing a graphene solid lubrication bearing in one embodiment of the present invention;

[0044] Figure 2 It is a structural schematic diagram of a bearing original part in a method for processing a graphene solid lubrication bearing in one embodiment of the present invention;

[0045] Figure 3 The figure is a schematic structural diagram of a bearing original component and a graphite module in a method for processing a graphene solid-state lubrication bearing in one embodiment of the present invention.

[0046] Description of main reference numerals:

[0047] 1. Outer ring; 2. Inner ring; 3. Cage; 4. Rolling element; 5. Graphite module. DETAILED DESCRIPTION

[0048] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0049] Reference Figure 1 The processing method of the graphene solid lubrication bearing in one embodiment of the present invention comprises the following steps:

[0050] S1. Provide pre-assembled bearing parts. Figure 2 The bearing assembly includes an outer ring 1, an inner ring 2, a retaining frame 3 disposed between the outer ring 1 and the inner ring 2, and a rolling element 4 mounted on the retaining frame 3.

[0051] S2. Remove dirt and impurities from the surface of the bearing original part through the automatic oil-water separation and filtration system of the ultrasonic cleaning equipment; transport the bearing original part to the drying area to blow away the moisture on the surface and inside of the bearing original part. In this embodiment, the ultrasonic cleaning equipment is equipped with the above-mentioned automatic oil-water separation and filtration system, which can ensure the recycling of cleaning water and reduce pollution to the environment.

[0052] S3, forming a sacrificial material layer on the surface of the retainer 3 and the rolling element 4 of the original bearing. Specifically, the original bearing is placed in a prefabricated mold; liquid sacrificial material is injected into the mold to form a sacrificial material layer on the surface of the retainer 3 and the rolling element 4 of the original bearing; after the sacrificial material layer is solidified, it is trimmed and excess sacrificial material and dust are removed.

[0053] In this embodiment, the sacrificial material layer is paraffin. When the paraffin is heated to melt, the wax liquid can flow and evenly cover the surface of the retaining frame 3 and the rolling element 4 in the bearing original component, and the sacrificial material layer is formed after the paraffin solidifies. At the same time, by trimming the sacrificial material layer, the uniformity of the thickness of the sacrificial material layer at different positions can be ensured.

[0054] S4, die-cast graphite powder between the outer ring 1 and the inner ring 2 of the original bearing to form a graphite mold 5 that wraps the cage 3 and the rolling element 4 (see Figure 3 ), and sintering and solidifying the graphite module 5. Specifically, the graphite powder can be die-casted between the outer ring 1 and the inner ring 2 of the bearing original by powder die-casting equipment. The servo hydraulic system of the powder die-casting equipment is adjusted to ensure the uniformity of the upper and lower mold pressures, so that the graphite powder is evenly filled around the cage 3 and the rolling element 4 between the two end surfaces of the bearing original, forming the graphite module 5.

[0055] The sintered and solidified graphite module 5 specifically comprises:

[0056] S41, performing the first sintering on the graphite module 5.

[0057] S42, cooling the graphite module 5 and the bearing original part, and polishing and milling the end faces of the graphite module 5 and the bearing original part. During the cooling process, the cooling speed and cooling time are controlled to ensure the uniformity and stability of the internal structure of the bearing original part and the graphite module 5. The purpose of the polishing process is to remove the burrs and irregular parts remaining on the surface so that the surface quality of the bearing meets the standard requirements. The purpose of the milling process is to ensure the concentricity of the end faces of the outer ring 1 and the inner ring 2 of the bearing.

[0058] S43, performing a second sintering on the graphite module 5.

[0059] The first sintering and second sintering steps of the graphite module 5 specifically include placing the bearing original part provided with the graphite module 5 in a high-temperature oven, setting the sintering temperature and sintering time, and taking out the bearing original part after sintering. Among them, the first sintering temperature range of the graphite module is 200℃~250℃, and the sintering time range is 1~1.5 hours; the second sintering temperature range of the graphite module is 350℃~400℃, and the sintering time range is 2.5~3 hours. The first sintering can preliminarily improve the material density and strength of the graphite module 5, and the second sintering can further strengthen the material density and strength of the graphite module 5 to ensure the performance of the graphite module 5.

[0060] In this embodiment, the first sintering temperature of the graphite module 5 is 200° C., the sintering time is 1 hour, and the second sintering temperature is 350° C., the sintering time is 2.5 hours. In other embodiments, the first sintering temperature of the graphite module 5 is 250° C., the sintering time is 1.5 hours; the second sintering temperature is 400° C., the sintering time is 3 hours. It can be understood that the sintering temperature and sintering time of the first sintering and the second sintering of the graphite module 5 can be set according to actual conditions.

[0061] S5, removing the sacrificial material layer, so that a gap is formed between the graphite module 5 and the retaining frame 3 and the rolling element 4, and a graphene solid lubrication bearing is obtained. In this embodiment, the sintering and curing temperature of the graphite module 5 is controlled so that the sacrificial material layer is liquefied or gasified, that is, sintering and curing the graphite module 5 and removing the sacrificial material layer are performed simultaneously. In other embodiments, sintering and curing the graphite module 5 and removing the sacrificial material layer may also be performed at different times.

[0062] Therefore, during the sintering process of the graphite module 5, the sacrificial material layer can be removed synchronously by utilizing the sintering and curing temperature, thereby enabling a gap to be formed between the graphite module 5 and the cage 3 and the rolling element 4. In the subsequent application of the bearing, due to the existence of the above-mentioned gap, friction and extrusion between the graphite module 5 and the cage 3 and the rolling element 4 of the bearing can be avoided as much as possible, thereby ensuring the self-lubricating effect and service life of the graphene solid lubrication bearing.

[0063] S6. Clamp the bearing and drive the bearing to rotate so that the forward and reverse concentricity of the bearing is within the range of 0.03 to 0.05 or -0.05 to -0.03. In the process of driving the bearing to rotate, the forward and reverse concentricity of the bearing can be further corrected so that the forward and reverse concentricity of the bearing is within the set range to ensure the overall accuracy and performance of the product.

[0064] S7, performing rotation torque inspection and surface visual inspection on the processed bearings, and selecting good products based on the inspection results;

[0065] Among them, when the rotational torque test result and the surface visual test result of the bearing both meet the requirements, the bearing is judged to be a good product; if either the rotational torque test result or the surface visual test result does not meet the requirements or both do not meet the requirements, the bearing is judged to be a defective product.

[0066] In this embodiment, there is no distinction between the order of rotational torque detection and surface visual detection, that is, the bearing can be subjected to rotational torque detection first and then surface visual detection; or it can be subjected to surface visual detection first and then rotational torque detection.

[0067] Specifically include:

[0068] S71, grab the bearing to a preset torque detection position, rotate the bearing and calculate its torque value;

[0069] Based on the comparison between the torque value and the preset torque value, it is determined whether the bearing is a defective product. In this embodiment, if the tested torque value is greater than the preset torque value, the bearing is judged to be a defective product and is automatically transferred to the unqualified area. No surface visual inspection is performed. Only after the inspection is qualified, surface visual inspection is performed again.

[0070] S72, grab the bearing to a preset visual inspection position, and obtain a bearing surface image through a camera;

[0071] De-noising of surface images based on deep learning algorithms;

[0072] Whether the bearing is defective is determined based on whether there are defects or cracks in the surface image. If defects or cracks are detected in the surface image, the bearing is judged as unqualified and automatically sent to the unqualified area. The rotation torque test will not be performed until the test is qualified.

[0073] Therefore, the bearing must meet both the rotation torque test and the surface visual test to be a good product. Through the above testing process, the accuracy and efficiency of bearing testing can be effectively improved to ensure the quality of the final product.

[0074] S8. Anti-rust coating is applied to the bearings by spraying oil on the surface and injecting oil inside. This step is to ensure that the bearings will not be corroded during storage.

[0075] S9. Press the end cover on one side of the bearing, turn the bearing over, and then press the end cover on the other side. The installation of the end cover on both sides of the bearing can be completed by automated equipment.

[0076] The processing method of the graphene solid-state lubrication bearing of the present invention can automatically control the processing of the bearing, improve the production efficiency of the graphene solid-state lubrication bearing, ensure the product quality, and is suitable for mass production of high-quality graphene solid-state lubrication bearings.

[0077] Among them, the formation and removal of the sacrificial material layer can avoid friction and extrusion between the graphite module 5 and the retaining frame 3 and the rolling element 4 when the bearing is in use as much as possible, thereby ensuring the self-lubricating effect and service life of the graphene solid-state lubrication bearing, while also increasing the flexibility of the bearing.

[0078] The secondary sintering of the graphite module 5 effectively improves the material density and structural strength of the bearing, providing a guarantee for the long-term use of the bearing under complex working conditions. Rotational torque detection and surface visual inspection can ensure the quality of the bearing products. Anti-rust coating can ensure that the bearing will not be corroded during processing and storage.

[0079] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

[0080] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A method for processing a graphene solid lubrication bearing, characterized in that: The following steps are involved: Provide pre-assembled bearing parts; forming a sacrificial material layer on the surfaces of the retaining frame and the rolling element of the bearing original component; Die-casting graphite powder between the outer ring and the inner ring of the bearing original component to form a graphite mold that wraps the retaining frame and the rolling body, and sintering and curing the graphite mold; The sacrificial material layer is removed to form a gap between the graphite module and the retaining frame and the rolling element, thereby obtaining a graphene solid lubrication bearing.

2. The method for processing a graphene solid lubrication bearing according to claim 1, characterized in that: Removing the sacrificial material layer to form a gap between the graphite module and the retaining frame and the rolling element specifically includes: The sintering and curing temperature of the graphite mold is controlled to liquefy or vaporize the sacrificial material layer.

3. The method for processing a graphene solid lubrication bearing according to claim 1, characterized in that: Sintering and curing the graphite module specifically comprises: Carrying out the first sintering of the graphite module; Cooling the graphite module and the bearing original component, and performing polishing and milling on the end surfaces of the graphite module and the bearing original component; The graphite mold is sintered a second time.

4. The method for processing a graphene solid lubrication bearing according to claim 3, characterized in that: The first sintering temperature range of the graphite module is 200°C to 250°C, and the sintering time range is 1 to 1.5 hours; the second sintering temperature range of the graphite module is 350°C to 400°C, and the sintering time range is 2.5 to 3 hours.

5. The method for processing a graphene solid lubrication bearing according to claim 1, characterized in that: Forming a sacrificial material layer on the surface of the retaining frame and the rolling element of the bearing original component specifically includes: Place the bearing assembly in a prefabricated mold; Injecting liquid sacrificial material into the mold to form a sacrificial material layer on the surface of the cage and rolling elements of the bearing original component; After the sacrificial material layer is solidified, it is trimmed and excess sacrificial material and dust are removed.

6. The method for processing a graphene solid lubrication bearing according to claim 1, characterized in that: The sacrificial material layer is paraffin.

7. The method for processing a graphene solid lubrication bearing according to claim 1, characterized in that: After providing the pre-assembled bearing components, the following steps are also included: The dirt and impurities on the surface of the bearing original part are removed by an automatic oil-water separation and filtration system of an ultrasonic cleaning device; The bearing components are transported to a drying area to remove moisture from the surface and interior of the bearing components.

8. The method for processing a graphene solid lubrication bearing according to claim 1, characterized in that: After the step of obtaining the graphene solid lubrication bearing, the method further includes the following steps: The processed bearings are subjected to rotation torque test and surface visual test respectively, and good products are selected based on the test results; Among them, when the rotational torque test result and the surface visual test result of the bearing both meet the requirements, the bearing is judged to be a good product; if either the rotational torque test result or the surface visual test result does not meet the requirements or both do not meet the requirements, the bearing is judged to be a defective product.

9. The method for processing a graphene solid lubrication bearing according to claim 8, characterized in that: The processed bearings are subjected to torque and visual inspections, and good products are selected based on the inspection results, including: Grab the bearing to the preset torque detection position, rotate the bearing and calculate its torque value; Based on the comparison between the torque value and the preset torque value, determining whether the bearing is defective; and / or, grabbing the bearing to a preset visual inspection position and acquiring an image of the bearing surface through a camera; Performing denoising on the surface image based on a deep learning algorithm; Based on whether there are defects or cracks in the surface image, it is determined whether the bearing is a defective product.

10. The method for processing a graphene solid lubrication bearing according to claim 8, characterized in that: Before the step of performing torque test and visual test on the processed bearings and selecting good products based on the test results, the following steps are also included: Clamp the bearing and drive the bearing to rotate so that the forward and reverse concentricity of the bearing is within the range of 0.03 to 0.05 or -0.05 to -0.03; And / or, after performing torque detection and visual detection on the processed bearings respectively and selecting good products based on the detection results, the following steps are also included: The bearings are coated with anti-rust paint inside and outside by spraying oil on the surface and filling oil inside. Press the end cover onto one side of the bearing, turn the bearing over and then press the end cover onto the other side.

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