Machining method for improving residual compressive stress of raceway surface of bearing ring

Abstract

A machining method for improving residual compressive stress of a raceway surface of a bearing ring relates to the technical field of bearing machining and comprises the following steps: turning a bearing ring blank, and then quenching and tempering a machined part; the surface of the ferrule raceway subjected to heat treatment is subjected to shot blasting machining strengthening; carrying out primary grinding processing on the surface of the reinforced ring raceway, and then carrying out additional tempering treatment; the surface of the ring raceway is subjected to fine grinding, and then the surface of the ring raceway is subjected to final grinding; and carrying out superfinishing on the surface of the ring raceway. According to the method, a machining procedure mutual matching strategy is adopted, the machining technological process is optimized, machining parameters of all procedures are strictly controlled in the machining process, through progressive machining of all the procedures, the surface residual compressive stress of the bearing ring raceway is gradually increased, good control over the residual compressive stress scattering difference is achieved, and the fatigue life of the bearing can be effectively prolonged. The residual compressive stress on the surface of the bearing ring raceway machined through the method is not smaller than 515 MPa, and the residual compressive stress range is not larger than 68 MPa.

Description

Technical Field

[0001] The invention relates to the technical field of bearing processing, and in particular to a processing method for improving residual compressive stress on a raceway surface of a bearing ring. Background Art

[0002] It is known that the life of the ring, as an important component of the bearing, directly determines the reliability of the bearing. Studies have shown that the residual stress distribution on the raceway surface of the bearing ring has an important influence on the initiation and expansion of cracks on the raceway surface, which in turn affects the fatigue life of the bearing. When there is residual compressive stress on the raceway surface of the bearing ring, it can effectively inhibit the initiation and expansion of cracks; conversely, residual tensile stress has a certain promoting effect on the generation of cracks. Therefore, controlling the residual compressive stress on the raceway surface of the bearing ring can improve the fatigue life of the bearing.

[0003] The existing bearing ring processing technology generally adopts the following operation process: turning the blank, and then quenching, tempering and cold treating in sequence, and then grinding to the product size for multiple times, but this type of process does not take into account the residual compressive stress generated on the raceway surface of the ring during the processing; therefore, the service life of the product does not meet the requirements. For example, Chinese patent document CN117283244A discloses a processing method for thin-walled bearing rings, which is achieved by turning the forging, and then quenching, tempering, cold treating and secondary tempering treatment steps, and grinding the heat-treated parts for multiple times, and finally finishing to obtain the bearing ring product. However, the main invention purpose of the above-mentioned bearing ring processing technology is to reduce the deformation of the ring during the processing and improve the processing accuracy of the raceway surface. It does not take into account the influence of the residual stress generated on the raceway surface of the ring during the processing, so it cannot improve the fatigue life of the bearing. Summary of the invention

[0004] The purpose of the present invention is to propose a processing method for improving the residual compressive stress on the raceway surface of a bearing ring, so that the residual compressive stress on the raceway surface of the bearing ring is gradually increased and good control of the residual compressive stress dispersion is achieved.

[0005] The technical solution adopted by the present invention is: a processing method for improving the residual compressive stress of the raceway surface of a bearing ring, comprising the following steps: S1. Turning the bearing ring blank, and then quenching and tempering the workpiece; S2. Strengthen the raceway surface of the heat-treated ferrule by shot peening, with the shot peening time being 0.5-1h; S3, performing preliminary grinding on the strengthened raceway surface of the ferrule, and then performing additional tempering treatment; performing fine grinding on the raceway surface of the ferrule, and then performing final grinding on the raceway surface of the ferrule; S4. Super finish the surface of the raceway of the ferrule to the product size and complete it.

[0006] The processing method for improving the residual compressive stress on the raceway surface of the bearing ring described in the present invention adopts a strategy of matching the processing steps, optimizes the processing process, strictly controls the processing parameters of each process during the processing, and gradually improves the residual compressive stress on the raceway surface of the bearing ring through the progressive processing of each process, and achieves good control of the residual compressive stress dispersion, which can effectively improve the fatigue life of the bearing. The residual compressive stress on the raceway surface of the bearing ring processed by the present invention is not less than 515 MPa, and the residual compressive stress range is not greater than 68 MPa.

[0007] As a preferred solution, in the present invention, the material of the bearing ring blank is GCr15SiMn steel.

[0008] As a preferred solution, in step S1, the quenching temperature is 810℃~820℃, the time is 50min~60min; the tempering temperature is 160℃±5℃, the time is 4h~5h. This solution improves the residual compressive stress and stress uniformity of the bearing ring raceway surface by strictly controlling the temperature and time parameters during heat treatment.

[0009] As a preferred solution, in order to improve processing efficiency and reduce processing costs, 100% water immersion ultrasonic testing is performed on the workpieces after machining to pick out products with internal defects in the bearing rings.

[0010] As a preferred solution, during the shot peening process of step S2, ceramic shots are used as the shot material, the shot diameter is 0.45-0.55mm, and the shot peening time is 0.5h~1h; the strengthening effect of the shot peening process on the raceway surface can effectively improve the basic compressive stress and stress uniformity of the ring.

[0011] As a preferred solution, in step S3, the tempering temperature of the additional tempering treatment is controlled at 140°C to 150°C, and the tempering time is 3h to 4h; this solution improves the residual compressive stress and stress uniformity on the raceway surface of the bearing ring by strictly controlling the temperature and time parameters during the additional tempering treatment.

[0012] As a preferred solution, in order to improve processing efficiency and reduce processing costs, after the initial grinding process, the rings are 100% pickled and checked for grinding burns, and the burned products are removed to obtain qualified products; after the final grinding process, the products are 100% magnetic particle inspected to pick out products with surface defects.

[0013] As a preferred solution, the machining process parameters are: the total cutting amount during machining is A1, the workpiece speed is 150r / min~450r / min, the feed speed is 0.2mm / r~0.4mm / r, and the cutting depth is 0.1mm~0.2mm; the initial grinding process parameters are: the total grinding amount during initial grinding is B1, the grinding wheel speed is 1000r / min~2000r / min, the workpiece speed is 400r / min~600r / min, the feed speed is 0.1mm / min~0.4mm / min, and the grinding wheel is WA60K6; the fine grinding process parameters are: the total grinding amount during fine grinding is C1, the grinding wheel speed is The speed is 1000r / min~2000r / min, the workpiece speed is 400r / min~600r / min, the feed speed is 0.05mm / min~0.15mm / min, and the grinding wheel is WA100K6; the final grinding parameters are: the total grinding amount during final grinding is D1, the grinding wheel speed is 1000r / min~2000r / min, the workpiece speed is 400r / min~600r / min, the feed speed is 0.01mm / min~0.1mm / min, and the grinding wheel is WA120K6; Among them, A1:B1:C1:D1=(0.4mm~0.5mm):(0.2 mm~0.25 mm):(0.15mm~0.2mm):(0.05 mm~0.08 mm); This scheme reasonably allocates the processing allowance of each process, and strictly controls the processing parameters of each process during the processing, so that the residual compressive stress on the surface of the bearing ring raceway is gradually increased and the stress uniformity is improved.

[0014] As a preferred solution, the superfinishing process parameters are: workpiece speed 150r / min~400r / min; coarse superfinishing oilstone pressure 0.9bar~1.3bar, fine superfinishing oilstone pressure 0.8bar~1.2bar, coarse superfinishing oilstone oscillation frequency 800 times / min~1600 times / min, fine superfinishing oilstone oscillation frequency 400 times / min~600 times / min; coarse superfinishing time 5s~10s, fine superfinishing time 3s~5s. DETAILED DESCRIPTION

[0015] The technical solution of the present invention is further described below in conjunction with specific embodiments.

[0016] Embodiment 1, The processing method for improving the residual compressive stress on the raceway surface of the bearing ring of this embodiment comprises the following specific steps: ①. According to the process requirements of bearing ring products, the ring blank is turned by CNC lathe. The ring blank is made of GCr15SiMn steel. After turning, the bearing ring workpiece is obtained. The workpiece speed during turning is 300r / min, the feed speed is 0.3mm / r, the cutting depth is 0.15mm, and the total cutting amount is 0.48mm. ② Use water immersion ultrasonic testing to inspect the workpieces and select the workpieces without cracks and other defects for subsequent processing; ③. Heat treatment is performed on the bearing ring turning workpiece to obtain a heat-treated part; the heat treatment is to quench and temper the bearing ring turning workpiece in sequence; wherein, the quenching temperature is 815°C, the time is 55min, the quenching cooling rate is 100°C / min, and the coolant used is quenching oil; the tempering temperature is 160°C, the time is 4.5h, the cooling rate after tempering is 20°C / min, and the coolant used is air; ④. Strengthen the heat-treated parts to obtain strengthened parts. The strengthening process is performed by shot peening, the shot diameter is 0.5mm, and the shot peening time is 0.7h. ⑤. Perform preliminary grinding on the raceway surface of the strengthened part to obtain the preliminary grinding part; the raceway is initially ground using a plunge grinder, the grinding wheel used is WA60K6, the grinding wheel speed is 1500r / min, the workpiece speed is 500r / min, the feed speed is 0.25mm / min, and the total grinding amount is 0.2mm; ⑥ Pickle the initially ground parts in turn, check whether there is grinding burn, remove the burnt products, and obtain qualified initially ground parts; ⑦. The qualified primary grinding parts are subjected to additional tempering treatment and fine grinding of the raceway in turn to obtain fine grinding parts; the tempering temperature is 145℃, the time is 3.5h, the cooling rate after tempering is 20℃ / min, and the coolant used is air; the raceway surface is finely ground using a plunge grinder, the grinding wheel is WA100K6, the grinding wheel speed is 1500r / min, the workpiece speed is 500r / min, the feed speed is 0.1mm / min, and the total grinding amount is 0.2mm; ⑧. The raceway surface of the finely ground parts is subjected to final grinding and magnetic particle flaw detection in turn to obtain qualified final ground parts, and finally the raceway surface of the qualified final ground parts is super-finished to obtain bearing rings; the raceway surface is final ground using a plunge grinder, the grinding wheel is WA120K6, the grinding wheel speed is 1500r / min, the workpiece speed is 500r / min, the feed speed is 0.05mm / min, and the total grinding amount is 0.07mm; the final ground parts are inspected by magnetic particle flaw detection, and qualified final ground parts without defects such as cracks are selected for subsequent processing; the raceway surface of the qualified final ground parts is super-finished using a plunge super-finishing machine, the workpiece speed is 300r / min, the coarse super-finishing oilstone pressure is 1.1bar, the fine super-finishing oilstone pressure is 1bar, the coarse super-finishing oilstone oscillation frequency is 1200 times / min, the fine super-finishing oilstone oscillation frequency is 500 times / min, the coarse super-finishing time is 8s, and the fine super-finishing time is 4s.

[0017] Embodiment 2, ①. According to the process requirements of bearing ring products, the ring blank is turned by CNC lathe. The ring blank is made of GCr15SiMn steel. After turning, the bearing ring workpiece is obtained. The workpiece speed during turning is 150r / min, the feed speed is 0.2mm / r, the cutting depth is 0.1mm, and the total cutting amount is 0.5mm. ② Use water immersion ultrasonic testing to inspect the workpieces and select the workpieces without cracks and other defects for subsequent processing; ③. Heat treatment is performed on the bearing ring turning workpiece to obtain a heat-treated part; the heat treatment is to quench and temper the bearing ring turning workpiece in sequence; wherein, the quenching temperature is 810°C, the time is 50min, the quenching cooling rate is 100°C / min, and the coolant used is quenching oil; the tempering temperature is 155°C, the time is 4h, the cooling rate after tempering is 20°C / min, and the coolant used is air; ④. Strengthen the heat-treated parts to obtain strengthened parts. The strengthening process is performed by shot peening, the shot diameter is 0.45mm, and the shot peening time is 0.5h; ⑤. Perform preliminary grinding on the raceway surface of the strengthened part to obtain the preliminary grinding part; the raceway is initially ground using a plunge grinder, the grinding wheel used is WA60K6, the grinding wheel speed is 1000r / min, the workpiece speed is 400r / min, the feed speed is 0.1mm / min, and the total grinding amount is 0.25mm; ⑥ Pickle the initially ground parts in turn, check whether there is grinding burn, remove the burnt products, and obtain qualified initially ground parts; ⑦. The qualified primary grinding parts are subjected to additional tempering treatment and fine grinding of the raceway in turn to obtain fine grinding parts; the tempering temperature is 140℃, the time is 3h, the cooling rate after tempering is 20℃ / min, and the coolant used is air; the raceway surface is finely ground using a plunge grinder, the grinding wheel is WA100K6, the grinding wheel speed is 1000r / min, the workpiece speed is 400r / min, the feed speed is 0.05mm / min, and the total grinding amount is 0.15mm; ⑧. The fine-grinded parts are subjected to final grinding of the raceway surface and magnetic particle flaw detection in turn to obtain qualified final-grinded parts, and finally the raceway surface of the qualified final-grinded parts is super-finished to obtain bearing rings; wherein, the raceway surface is final-grinded by a plunge grinder, the grinding wheel is WA120K6, the grinding wheel speed is 1000r / min, the workpiece speed is 400r / min, the feed speed is 0.01mm / min, and the total grinding amount is 0.05mm; the final-grinded parts are inspected by magnetic particle flaw detection, and qualified final-grinded parts without defects such as cracks are selected for subsequent processing; the raceway surface of the qualified final-grinded parts is super-finished by a plunge-type super-finishing machine, the workpiece speed is 150r / min, the coarse super-finishing oilstone pressure is 0.9bar, the fine super-finishing oilstone pressure is 0.8bar, the coarse super-finishing oilstone oscillation frequency is 800 times / min, the fine super-finishing oilstone oscillation frequency is 400 times / min, the coarse super-finishing time is 5s, and the fine super-finishing time is 3s.

[0018] Embodiment 3, ①. According to the process requirements of bearing ring products, the ring blank is turned by CNC lathe. The ring blank is made of GCr15SiMn steel. After turning, the bearing ring workpiece is obtained. The workpiece speed during turning is 450r / min, the feed speed is 0.4mm / r, the cutting depth is 0.2mm, and the total cutting amount is 0.45mm. ② Use water immersion ultrasonic testing to inspect the workpieces and select the workpieces without cracks and other defects for subsequent processing; ③, heat treatment is performed on the bearing ring turning workpiece to obtain a heat-treated part; the heat treatment is to quench and temper the bearing ring turning workpiece in sequence; wherein, the quenching temperature is 820°C, the time is 60min, the quenching cooling rate is 100°C / min, and the coolant used is quenching oil; the tempering temperature is 165°C, the time is 5h, the cooling rate after tempering is 20°C / min, and the coolant used is air; ④. Strengthen the heat-treated parts to obtain strengthened parts. The strengthening process is performed by shot peening, the shot diameter is 0.55mm, and the shot peening time is 1h; ⑤. Perform preliminary grinding on the raceway surface of the strengthened treated part to obtain the preliminary ground part; the raceway is initially ground using a plunge grinder, the grinding wheel used is WA60K6, the grinding wheel speed is 2000r / min, the workpiece speed is 600r / min, the feed speed is 0.4mm / min, and the total grinding amount is 0.24mm; ⑥ Pickle the initially ground parts in turn, check whether there is grinding burn, remove the burnt products, and obtain qualified initially ground parts; ⑦. The qualified primary grinding parts are subjected to additional tempering treatment and fine grinding of the raceway in turn to obtain fine grinding parts; the tempering temperature is 150℃, the time is 4h, the cooling rate after tempering is 20℃ / min, and the coolant used is air; the raceway surface is finely ground using a plunge grinder, the grinding wheel is WA100K6, the grinding wheel speed is 2000r / min, the workpiece speed is 600r / min, the feed speed is 0.15mm / min, and the total grinding amount is 0.18mm; ⑧. The raceway surface of the finely ground parts is subjected to final grinding and magnetic particle flaw detection in turn to obtain qualified final ground parts, and finally the raceway surface of the qualified final ground parts is super-finished to obtain bearing rings; wherein, the raceway surface is final ground using a plunge grinder, the grinding wheel is WA120K6, the grinding wheel speed is 2000r / min, the workpiece speed is 600r / min, the feed speed is 0.0=1mm / min, and the total grinding amount is 0.08mm; the final ground parts are inspected using magnetic particle flaw detection, and qualified final ground parts without defects such as cracks are selected for subsequent processing; the raceway surface of the qualified final ground parts is super-finished using a plunge super-finishing machine, the workpiece speed is 400r / min, the coarse super-finishing oilstone pressure is 1.3bar, the fine super-finishing oilstone pressure is 1.2bar, the coarse super-finishing oilstone oscillation frequency is 1600 times / min, the fine super-finishing oilstone oscillation frequency is 600 times / min, the coarse super-finishing time is 10s, and the fine super-finishing time is 5s.

[0019] Comparative Example 1: The difference between the processing method for improving the residual compressive stress on the bearing ring raceway surface of this comparative example and the processing method for improving the residual compressive stress on the bearing ring raceway surface of Example 1 is that the processing method for improving the residual compressive stress on the bearing ring raceway surface of this comparative example omits step ④ of the strengthening treatment process.

[0020] Comparative Example 2: The difference between the processing method for improving the residual compressive stress on the bearing ring raceway surface of this comparative example and the processing method for improving the residual compressive stress on the bearing ring raceway surface of Example 1 is that the quenching temperature in step ③ of the processing method for improving the residual compressive stress on the bearing ring raceway surface of this comparative example is adjusted to 870°C.

[0021] Comparative Example 3: The difference between the processing method for improving the residual compressive stress on the bearing ring raceway surface of this comparative example and the processing method for improving the residual compressive stress on the bearing ring raceway surface of Example 1 is that this comparative example omits the additional tempering treatment in step ⑦, and adjusts the tempering treatment process parameters in step ③ to control the tempering temperature at 145°C and the time at 3.5h.

[0022] Comparative Example 4: The difference between the processing method for improving the residual compressive stress of the bearing ring raceway surface of this comparative example and the processing method for improving the residual compressive stress of the bearing ring raceway surface of Example 1 is that the feed speeds of turning, initial grinding, fine grinding and final grinding of the raceway surface in steps ① ⑤ ⑦ ⑧ are 0.5mm / r, 0.5mm / min, 0.2mm / min and 0.15mm / min respectively, the coarse super oilstone pressure is 1.4bar, and the fine super oilstone pressure is 1.3bar.

[0023] Comparative Example 5: The difference between the processing method for improving the residual compressive stress of the bearing ring raceway surface in this comparative example and the processing method for improving the residual compressive stress of the bearing ring raceway surface in Example 1 is that the turning amount of the turning, the grinding amount of the initial grinding, the grinding amount of the fine grinding and the grinding amount of the final grinding in steps ① ⑤ ⑦ ⑧ are 0.38mm, 0.27mm, 0.21mm and 0.09mm respectively.

[0024] Test example: In order to evaluate the residual compressive stress of bearing rings prepared by different processing methods, the residual compressive stress of the raceway surface of the bearing rings prepared by Examples 1-3 and Comparative Examples 1-5 was tested according to the same method (the number of bearing rings processed by the above methods was 30), and then the range of residual compressive stress was calculated. The results are shown in Table 1. The "-" sign in the residual compressive stress value in Table 1 only represents the residual compressive stress. The range of residual compressive stress in Table 1 is equal to the difference between the maximum and minimum values ​​of the residual compressive stress tested on the same sample. It should be noted that the residual compressive stress in Table 1 represents the minimum value of the residual compressive stress of 30 bearing rings processed by different processing methods.

[0025] Table 1 Residual compressive stress and residual compressive stress range of bearing rings prepared by different processing methods It can be seen from Table 1 that Examples 1-3 strictly adopt the process flow and process parameters defined in the present invention, and the residual compressive stress on the raceway surface of the processed bearing ring is as low as 515 MPa, the extreme difference of residual compressive stress is not more than 68MPa; Comparative Example 1 cancels the strengthening treatment process, resulting in poor stress uniformity on the ring roller surface, which can be seen from the data in Table 1 that the final performance of the product is greatly affected; in Comparative Example 2, the quenching temperature in step ③ is adjusted to 870℃, while the optimal quenching temperature is 810℃~820℃, which deviates from the optimal temperature range, and ultimately affects the performance of the product; in Comparative Example 3, the additional tempering treatment is omitted, so that the residual compressive stress and stress uniformity on the surface of the bearing ring raceway cannot be improved. At the same time, the tempering treatment process parameters in step ③ are adjusted to control the tempering temperature at 145℃ and the time at 3.5h, while the optimal tempering temperature is 160℃±5℃ and the time is 4h~5h, which makes it out of the optimal treatment temperature and time range, thereby affecting the performance of the product; Comparative Examples 4 and 5 respectively change the feed speed and grinding amount in the four processing processes of turning, primary grinding, fine grinding and final grinding, which also affect the performance of the final product to a certain extent; However, due to the unreasonable process flow, the bearing rings of the same material and specification on the market have a minimum residual compressive stress of 430MPa on the raceway surface of the processed bearing rings, and the range of residual compressive stress is no more than 90MPa. By comparing the residual compressive stress and compressive stress range data in Table 1, it can be known that the product prepared by the method defined in the present invention has obvious advantages. At the same time, it can be seen from Table 1 that the roughness parameter of the bearing ring raceway surface prepared by the process method defined in the present invention is not greater than 0.07μm, the roughness parameter of the bearing ring raceway surface prepared in Comparative Examples 1-5 is not greater than 0.08μm, and the roughness parameter of the commercially available ring raceway surface is not greater than 0.08μm. It can be seen that the bearing ring raceway surface accuracy processed by the present invention is slightly improved.

[0026] The parts not described in detail in the above embodiments are prior art.

[0027] It should be noted that although the various steps of the present invention are described through the above embodiments, the present invention may also have other various embodiments. Without departing from the spirit and scope of the present invention, it is obvious that those skilled in the art may make various corresponding changes and deformations to the present invention, but these changes and deformations should all fall within the scope of protection of the appended claims of the present invention and their equivalents.

Claims

1. A processing method for improving the residual compressive stress of the raceway surface of a bearing ring, characterized in that: The steps include: S1. Turning the bearing ring blank, and then quenching and tempering the machined part; S2. Strengthen the raceway surface of the heat-treated ferrule by shot peening, with the shot peening time being 0.5-1h; S3, performing preliminary grinding on the strengthened raceway surface of the ferrule, and then performing additional tempering treatment; performing fine grinding on the raceway surface of the ferrule, and then performing final grinding on the raceway surface of the ferrule; S4. Super finish the surface of the raceway of the ferrule to the product size and complete it.

2. A processing method for improving residual compressive stress on a bearing ring raceway surface according to claim 1, characterized in that: In step S1, the quenching temperature is 810°C to 820°C, and the time is 50min to 60min.

3. A processing method for improving residual compressive stress on a bearing ring raceway surface according to claim 1, characterized in that: In step S1, the tempering temperature is 160°C ± 5°C, and the time is 4h to 5h.

4. A processing method for improving residual compressive stress on a bearing ring raceway surface according to claim 1, characterized in that: In step S2, during the shot peening process, the shot material is ceramic shot, the shot diameter is 0.45-0.55 mm, and the shot peening time is 0.5h to 1h.

5. A processing method for improving residual compressive stress on a bearing ring raceway surface according to claim 1, characterized in that: In step S3, the additional tempering treatment is performed at a tempering temperature of 140°C to 150°C and a tempering time of 3h to 4h.

6. A processing method for improving residual compressive stress on a bearing ring raceway surface according to claim 1, characterized in that: Step S1 also includes the step of performing water immersion ultrasonic flaw detection on the workpiece after machining.

7. A processing method for improving residual compressive stress on a bearing ring raceway surface according to claim 1, characterized in that: In step S3, after the initial grinding process, the step of pickling the processed ring is also included; after the final grinding process, the step of flaw detection of the processed ring is also included.

8. A processing method for improving residual compressive stress on a bearing ring raceway surface according to any one of claims 1 to 7, characterized in that: The machining process parameters are: workpiece speed: 150r / min~450r / min, feed speed: 0.2mm / r~0.4mm / r, cutting depth: 0.1mm~0.2mm; The initial grinding process parameters are: grinding wheel speed 1000r / min~2000r / min, workpiece speed 400r / min~600r / min, feed speed 0.1mm / min~0.4mm / min; Fine grinding process parameters are: grinding wheel speed 1000r / min~2000r / min, workpiece speed 400r / min~600r / min, feed speed 0.05mm / min~0.15mm / min; Final grinding parameters are: grinding wheel speed 1000r / min~2000r / min, workpiece speed 400r / min~600r / min, feed speed 0.01mm / min~0.1mm / min.

9. A processing method for improving residual compressive stress on a bearing ring raceway surface according to claim 8, characterized in that: The total cutting amount during turning is A1, the total grinding amount during initial grinding is B1, the total grinding amount during fine grinding is C1, and the total grinding amount during final grinding is D1, among which A1:B1:C1:D1=(0.4mm~0.5mm):(0.2 mm~0.25 mm):(0.15mm~0.2mm):(0.05 mm~0.08 mm).

10. A processing method for improving residual compressive stress on a bearing ring raceway surface according to claim 8, characterized in that: The super finishing process parameters are: workpiece speed 150r / min~400r / min; rough super finishing oilstone pressure 0.9bar~1.3bar, fine super finishing oilstone pressure 0.8bar~1.2bar, rough super finishing oilstone oscillation frequency 800 times / min~1600 times / min, fine super finishing oilstone oscillation frequency 400 times / min~600 times / min; rough super finishing time 5s~10s, fine super finishing time 3s~5s.

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