Repairing method for turntable bearing

Abstract

The invention relates to a turntable bearing repairing method which comprises the following steps: detecting the assembly height, clearance and matching surface size of a bearing to be repaired, and detecting the rotation precision of the bearing to be repaired; dismounting the bearing, detecting the damage conditions inside and on the surface of the bearing ring, and determining a repair scheme; determining the grinding amount of a raceway and a flange of the bearing ring according to the damage condition of the bearing ring, and then grinding the bearing ring; a new roller is selected according to the raceway grinding amount, the bearing ring and the selected roller are sleeved, the clearance value, the bearing assembly height and the matching face size are measured, and after the selected new roller and the ground bearing ring are assembled, the assembly height, the clearance and the matching face size of the bearing are kept consistent with those of the bearing before repairing; and assembling: detecting whether the rotation is stable after grease injection, and detecting whether the rotation precision is consistent with the rotation precision of the bearing before repairing. Therefore, it is guaranteed that the assembly height of the repaired bearing is high, the clearance and the rotating precision can meet the requirements, and the procedure is simple.

Description

Technical Field

[0001] The invention relates to the field of mechanical basic parts, and in particular to a turntable bearing repair method. Background Art

[0002] As a key component required by large-scale engineering machinery, turntable bearings are widely used in shield machines, wind turbines, radar transmitters and other products. Turntable bearings bear huge loads when working, so it is inevitable that noise and unstable operation will occur due to raceway damage. In addition, turntable bearings must also meet strict precision requirements. In order to respond to the country's call for sustainable development and reduce costs, timely repair of damaged bearings has become the only choice for host manufacturers.

[0003] Three-row cylindrical roller bearings are one of the most common slewing bearings. They are subjected to high loads during operation, which causes indentations on the raceway surface of the three-row cylindrical roller bearings. If the seal fails and impurities enter the bearing cavity, scratches will appear on the raceway and ribs, affecting the normal use of the raceway.

[0004] Existing bearing repair methods, such as the main bearing disassembly method and main bearing maintenance method of the shield machine main drive disclosed in the Chinese invention patent application with application publication number CN110238791A and application publication date September 17, 2019, the main bearing maintenance method in the invention is to first completely disassemble the bearing, and then check the wear of the inner and outer ring raceways to replace or repair the worn parts. If the depth of the groove worn on the raceway surface of the inner or outer ring is 3-5mm, the raceway surface is repaired. During the repair, the groove on the raceway surface is welded with a wear-resistant welding rod, and then the welded area is polished, and then the polished area is electroplated; if the depth of the groove worn on the raceway surface of the inner or outer ring is greater than 5mm, the component where the raceway surface is located is replaced.

[0005] The invention is used to repair the main bearings of the shield machine after operation, avoiding the direct scrapping of the damaged main bearings, which will increase the cost of use. By repairing the main bearings of the shield machine, the working efficiency of the main bearings when the shield machine is used again is improved, thereby improving the working efficiency of the entire shield machine. Through surfacing, grinding and electroplating treatments, the smoothness and wear resistance of the trimmed slide surface and raceway surface can be ensured. Since the main bearings of the shield machine are large, surfacing, grinding and electroplating require a long time. When using the invention to repair the bearings, there are many steps and the entire repair process is relatively complicated. Summary of the invention

[0006] The purpose of the present invention is to provide a turntable bearing repair method for solving the problem that there are many working steps and the whole repair process is relatively complicated when repairing the bearing in the prior art.

[0007] In order to solve the above technical problems, the present invention adopts the following technical solutions.

[0008] A method for repairing a turntable bearing, characterized in that it comprises the following steps: Step S1: Detecting the assembly dimensions of the bearing to be repaired, including assembly height, clearance and mating surface dimensions, and detecting the rotation accuracy of the bearing to be repaired; Step S2: disassemble the bearing, inspect the inside of the bearing ring, the raceway and the tooth surface. If there are defects inside the bearing ring or the raceway surface of the bearing ring is completely detached or the tooth surface is too worn to mesh, the ring needs to be replaced as a whole. Otherwise, proceed to the next step. Step S3: determining the grinding amount of the raceway and rib of the bearing ring according to the damage condition of the bearing ring, and then grinding the bearing ring; Step S4: selecting a new roller according to the grinding amount of the raceway, fitting the bearing ring and the selected roller, measuring the clearance value, the bearing assembly height and the matching surface size, so that after the selected new roller is assembled with the ground bearing ring, the bearing assembly height, clearance and matching surface size are consistent with those of the bearing before repair; Step S5: Assembling, checking whether the rotation is smooth after grease injection, and checking whether the rotation accuracy is consistent with the rotation accuracy of the bearing before repair.

[0009] Furthermore, in step S3, the grinding amount is consistent with the depth of the raceway at the point where the wear degree is the largest, and it is necessary to ensure that the depth of the hardened layer of the bearing ring after grinding meets the use requirements.

[0010] Furthermore, when grinding the raceway and the rib of the bearing ring in step S3, the grinding is performed based on the mutual reference principle.

[0011] Furthermore, between step S3 and step S4, the bearing ring is subjected to a magnetic particle inspection to determine whether the surface cracks of the raceway ribs have been completely removed.

[0012] Further, in step S4, a roller is selected according to the grinding amount of the raceway of the bearing ring, and the diameter of the roller is 10-20 microns larger than the calculated diameter value, so that the axial and radial clearance values ​​are smaller. By continuing to grind the raceway, the axial and radial clearance values ​​will gradually increase, thereby ensuring that the clearance value remains consistent with the clearance value of the bearing before repair.

[0013] Further, in step S4, when fitting, the ground rings are assembled, 10-15 rollers are evenly placed between the rings, and then the clearance, assembly height and mating surface size are measured.

[0014] Furthermore, between step S4 and step S5, the non-matching surface of the bearing is polished, and the bearing ring is soaked in kerosene to facilitate cleaning of grease, impurities and rust in the hole inside the bearing.

[0015] Furthermore, the external teeth are processed by gear grinding.

[0016] Furthermore, in step S1, the starting torque of the bearing to be repaired is also detected. In step S5, after assembly is completed, the repaired bearing is greased and idling, the bearing's operating condition is detected, and the bearing's friction torque is tested to ensure that the operating condition of the bearing after repair is consistent with the operating condition of the bearing before repair.

[0017] The above technical scheme has the following beneficial effects: the present invention innovatively proposes a turntable bearing repair method, by grinding the worn raceway surface and replacing the roller with a larger diameter, so as to ensure that the assembly height, clearance and rotation accuracy of the repaired bearing can meet the requirements, and the repair process is simple and convenient for maintenance. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a cross-sectional view of a three-row cylindrical roller bearing; Figure 2 It is a cross-sectional view of the outer ring of a three-row cylindrical roller bearing; Figure 3 It is a cross-sectional view of the first inner ring of a three-row cylindrical roller bearing; Figure 4 This is a cross-sectional view of the second inner ring of a three-row cylindrical roller bearing.

[0019] In the figure: 1, outer ring; 2, first inner ring; 3, second inner ring; 4, main thrust roller; 5, auxiliary thrust roller; 6, radial roller; h, bearing assembly height; 11, external teeth; 12, outer ring raceway; 13, outer ring rib; 14, outer diameter matching surface; 21, first inner ring inner diameter matching surface; 22, first inner ring raceway; 23, first inner ring rib; 31, second inner ring inner diameter matching surface; 32, second inner ring raceway; 33, second inner ring rib. DETAILED DESCRIPTION

[0020] The features and performance of the present invention are further described in detail below in conjunction with the embodiments.

[0021] The present invention provides a turntable bearing repair method. In view of the existing bearing repair method, when repairing the bearing, there are many procedures and the entire repair process is relatively complicated. The turntable bearing repair method of the present invention grinds the worn raceway surface and replaces the roller with a larger diameter, so as to ensure that the assembly height, clearance and rotation accuracy of the repaired bearing can meet the requirements, and the repair procedure is simple and convenient for maintenance.

[0022] In a basic embodiment, to repair Figure 1 The three-row cylindrical roller bearing shown in the figure is taken as an example, comprising an outer ring 1, a first inner ring 2 and a second inner ring 3, and a main thrust roller 4, an auxiliary thrust roller 5 and a radial roller 6 are arranged between the outer ring 1 and the first inner ring 2 and the second inner ring 3.

[0023] Before repair, it is necessary to determine the maximum grinding amount of the raceway, ensure the surface hardness and hardened layer depth of the raceway, and eliminate the surface damage of the raceway, so as to formulate a repair plan.

[0024] When the repair plan is feasible, the bearing to be repaired is first cleaned to remove impurities on its surface to ensure that the assembly dimensions of the bearing to be repaired can be accurately measured, and then the following steps are used to repair the three-row cylindrical roller bearing.

[0025] Step S1: Detecting the assembly dimensions of the bearing to be repaired, including assembly height, clearance and mating surface dimensions, and detecting the rotation accuracy of the bearing to be repaired; Step S2: disassemble the bearing, inspect the inside of the bearing ring, the raceway and the tooth surface. If there are defects inside the bearing ring or the raceway surface of the bearing ring is completely detached or the tooth surface is too worn to mesh, the ring needs to be replaced as a whole. Otherwise, proceed to the next step. Step S3: determining the grinding amount of the raceway and rib of the bearing ring according to the damage condition of the bearing ring, and then grinding the bearing ring; Step S4: selecting a new roller according to the grinding amount of the raceway, fitting the bearing ring and the selected roller, measuring the clearance value, the bearing assembly height and the matching surface size, so that after the selected new roller is assembled with the ground bearing ring, the bearing assembly height, clearance and matching surface size are consistent with those of the bearing before repair; Step S5: Assembling, checking whether the rotation is smooth after grease injection, and checking whether the rotation accuracy is consistent with the rotation accuracy of the bearing before repair.

[0026] In the above embodiment, after the bearing is disassembled in step S2, the components are first cleaned, and then the bearing ring is inspected. When the raceway surface of the bearing ring is subjected to magnetic particle inspection, the possibility of repair is judged by observing the defect level of the raceway surface. If the repairable conditions are not met, the bearing ring needs to be replaced as a whole.

[0027] On the basis of the above-mentioned embodiment, when determining the grinding amount of the raceway, according to the flaw detection results of the raceway, the point where the raceway wears the most is taken as the depth required for grinding, and it is necessary to ensure that the depth of the hardened layer of the bearing ring after grinding meets the use requirements. If the depth of the hardened layer of the bearing ring after grinding cannot meet the use requirements, it is necessary to replace the bearing ring as a whole or use secondary surface quenching treatment of the raceway.

[0028] Based on the above embodiments, Figure 1 As shown, the main matching dimensions of the three-row cylindrical roller bearing are the diameter of the outer diameter matching surface 14, the diameter of the first inner ring inner diameter matching surface 21 and the diameter of the second inner ring inner diameter matching surface 31, the bearing assembly height h, the parameters of the outer teeth 11 and the clearance value. The damage of the three-row roller turntable bearing is mostly reflected in the damage of the raceway. Therefore, the repair of the raceways of the outer ring 1, the first inner ring 2 and the second inner ring 3 is an important factor to ensure the repair result. When grinding the bearing ring, the principle of datum coincidence can be adopted for grinding, so that the positioning datum is the design datum, or the unified datum principle can be adopted for grinding. In a preferred embodiment, the principle of mutual datum is adopted when grinding the raceway and the rib of the bearing ring.

[0029] When grinding the outer ring 1, Figure 2 As shown, firstly, the outer diameter matching surface 14 is ground based on the outer ring rib 13, and then the outer ring rib 13 and the outer ring raceway 12 are ground based on the outer diameter matching surface 14.

[0030] When grinding the first inner ring 2, if Figure 3 As shown, the first inner ring inner diameter matching surface 21 is ground based on the first inner ring rib 23, and then the first inner ring rib 23 and the first inner ring raceway 22 are ground based on the first inner ring inner diameter matching surface 21.

[0031] When grinding the second inner ring 3, Figure 4 As shown, the second inner ring inner diameter matching surface 31 is firstly ground with the second inner ring rib 33 as a reference, and then the second inner ring rib 33 and the second inner ring raceway 32 are ground with the second inner ring inner diameter matching surface 31 as a reference.

[0032] After the grinding of the bearing ring is completed, magnetic particle inspection is performed to confirm that the raceway and flange of the bearing ring are completely cleaned. Grinding the bearing ring in this way can ensure the coaxiality of the bearing ring. The ring is placed in a kerosene pool for soaking and cleaning to clean the impurities on the surface of the bearing ring and the rust in the hole. In particular, it is necessary to pay attention to the fact that no impurities can be attached to the surface of the raceway to prevent impurities from being left in the cavity after assembly to damage the rollers and raceways.

[0033] Preferably, the two mating end faces where the bearing assembly height h is located are precisely matched with the external connecting parts, impurities are difficult to enter, the surface is relatively smooth, and polishing is sufficient. The tooth surface meshing of the external teeth 11 can also be processed by grinding to ensure the surface quality. At the same time, it is necessary to control the grinding amount and the tooth normal deviation to ensure that the external teeth 11 can mesh normally.

[0034] On the basis of the above embodiment, the grinding amount of the outer ring raceway 12, the first inner ring raceway 22 and the second inner ring raceway 32 is recorded respectively, and the diameter of the roller to be replaced is accurately calculated according to the grinding amount of the raceway, so as to select a new roller, so that the bearing assembly height h, clearance and matching surface size after the repair are consistent with those before the repair. The increased diameter of the main thrust roller 4 and the auxiliary thrust roller 5 is used to compensate for the grinding amount in the axial direction, and the radial roller 6 is used to compensate for the grinding amount in the radial direction, so as to ensure that the bearing assembly height h, the diameter of the outer diameter matching surface 14, the diameter of the first inner ring inner diameter matching surface 21 and the diameter of the second inner ring inner diameter matching surface 31 of the bearing after the repair are consistent with those before the repair.

[0035] Since there are errors when grinding the raceways of the bearing rings, in a preferred embodiment, in order to ensure that the clearance value remains the same as before repair, the diameter of the replaced roller needs to be 10-20 microns larger than the roller diameter calculated by the grinding amount, so that the clearance value of the bearing can be easily adjusted.

[0036] When the roller diameter is too large, the axial and radial clearance values ​​of the bearing will be small. By continuing to grind the raceway, the axial and radial clearance values ​​will gradually increase. According to the clearance value measured during assembly, the raceway of the ferrule is ground twice to ensure the clearance value. By evenly grinding the outer ring raceway 12, the first inner ring raceway 22 and the second inner ring raceway 32, the axial clearance and radial clearance are increased to ensure that the clearance value is consistent with the clearance value of the bearing before repair.

[0037] On the basis of the above embodiment, when fitting, the outer ring 1, the first inner ring 2 and the second inner ring 3 which have been ground are assembled, and a plurality of new rollers can be evenly placed between each raceway, and then the clearance value, the bearing assembly height h and the assembly surface size of the bearing are measured. In a preferred embodiment, 10-15 new rollers are evenly placed along the circumferential direction between each raceway, so that it is convenient to measure the clearance value, the bearing assembly height h and the assembly surface size of the bearing.

[0038] In a preferred embodiment, in step S1, the starting torque of the bearing to be repaired is also detected. In step S6, after assembly is completed, the repaired bearing is greased and idling, the operating condition of the bearing is detected, and the friction torque of the bearing is tested to ensure that the operating condition of the bearing after repair is consistent with that of the bearing before repair.

[0039] The bearing rings that have been finally ground are soaked in kerosene again to clean the impurities and rust on their surfaces, especially the raceway surface. The bearing rings and the selected new rollers are then assembled together for testing. The clearance value, bearing assembly height h and assembly surface size of the assembled bearing are measured to see if they are consistent with those of the bearing before repair. At the same time, the rotation accuracy and grease injection friction torque of the bearing after assembly are tested to ensure that the operating condition of the bearing after repair is consistent with that of the bearing before repair. Finally, a final report is generated to complete the repair.

[0040] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. The patent protection scope of the present invention shall be based on the claims. All equivalent structural changes made using the contents of the description and drawings of the present invention should also be included in the protection scope of the present invention.

Claims

1. A method for repairing a turntable bearing, characterized in that: The following steps are involved: Step S1: Detecting the assembly dimensions of the bearing to be repaired, including assembly height, clearance and mating surface dimensions, and detecting the rotation accuracy of the bearing to be repaired; Step S2: disassemble the bearing, inspect the inside of the bearing ring, the raceway and the tooth surface. If there are defects inside the bearing ring or the raceway surface of the bearing ring is completely detached or the tooth surface is too worn to mesh, the ring needs to be replaced as a whole. Otherwise, proceed to the next step. Step S3: determining the grinding amount of the raceway and rib of the bearing ring according to the damage condition of the bearing ring, and then grinding the bearing ring; Step S4: selecting a new roller according to the grinding amount of the raceway, fitting the bearing ring and the selected roller, measuring the clearance value, the bearing assembly height and the matching surface size, so that after the selected new roller is assembled with the ground bearing ring, the bearing assembly height, clearance and matching surface size are consistent with those of the bearing before repair; Step S5: Assembling, checking whether the rotation is smooth after grease injection, and checking whether the rotation accuracy is consistent with the rotation accuracy of the bearing before repair.

2. The turntable bearing repair method according to claim 1, characterized in that: In step S3, the grinding amount is consistent with the depth of the raceway where the wear degree is the largest, and it is necessary to ensure that the depth of the hardened layer of the bearing ring after grinding meets the use requirements.

3. The turntable bearing repair method according to claim 1, characterized in that: When grinding the raceway and rib of the bearing ring in step S3, the grinding is performed based on the mutual reference principle.

4. The turntable bearing repair method according to claim 1, characterized in that: Between step S3 and step S4, the bearing ring is subjected to another magnetic particle inspection to determine whether the surface cracks of the raceway ribs have been completely removed.

5. The turntable bearing repair method according to claim 1, characterized in that: In step S4, a roller is selected according to the grinding amount of the raceway of the bearing ring. The diameter of the roller is 10-20 microns larger than the calculated diameter value so that the axial and radial clearance values ​​are smaller. By continuing to grind the raceway, the axial and radial clearance values ​​will gradually increase, thereby ensuring that the clearance value remains consistent with the clearance value of the bearing before repair.

6. The turntable bearing repair method according to claim 1, characterized in that: In step S4, when fitting, the ground rings are assembled, 10-15 rollers are evenly placed between the rings, and then the clearance, assembly height and mating surface size are measured.

7. The turntable bearing repair method according to any one of claims 1 to 6, characterized in that: Between step S4 and step S5, the non-matching surface of the bearing is polished, and the bearing ring is soaked in kerosene to facilitate cleaning of grease, impurities and rust in the hole inside the bearing.

8. The turntable bearing repair method according to claim 7, characterized in that: The external teeth are processed by grinding.

9. The turntable bearing repair method according to any one of claims 1 to 6, characterized in that: In step S1, the starting torque of the bearing to be repaired is also detected. In step S5, after assembly is completed, the repaired bearing is greased and idling, the bearing's operating condition is detected, and the bearing's friction torque is tested to ensure that the operating condition of the bearing after repair is consistent with the operating condition of the bearing before repair.

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