High-strength wind power main shaft bearing and machining method thereof

Abstract

The invention discloses a high-strength wind power main shaft bearing and a processing method thereof, and the method comprises the following steps: S1, raw material preparation: a, blank selection: selecting high-strength alloy structural steel containing Cr, Ni and Mo elements as a bearing blank, wherein the content of the Cr element is 1.5%-2.0%, the content of the Ni element is 0.8%-1.2%, and the content of the Mo element is 0.2%-0.5%; high-strength alloy structural steel containing Cr, Ni and Mo is selected as a blank, the Cr element is used for improving abrasion resistance and hardenability, the Ni element is used for enhancing toughness and fatigue resistance, the Mo element is used for improving high-temperature strength and tempering-resistant stability, the performance bottleneck of a traditional material is broken through from the raw material level, meanwhile, through homogenizing annealing in the blank pretreatment stage, the hardness of the blank is improved, and the hardness of the blank is improved. The structure segregation in the blank is effectively eliminated, the uniformity of material components and structures is guaranteed, a stable material foundation is laid for subsequent machining procedures, and local stress concentration and early failure caused by uneven materials are avoided.

Description

Technical Field

[0001] This invention relates to the field of bearing manufacturing technology, specifically to a high-strength wind turbine main shaft bearing and its processing method. Background Technology

[0002] With the booming development of the wind power industry, wind turbine main shaft bearings, as the core components of wind turbine generators, are bearing increasingly enormous loads and operating conditions that are becoming increasingly complex. However, existing wind turbine main shaft bearings on the market have revealed many problems in practical applications. Among them, insufficient strength is one of the most prominent issues. Traditional wind turbine main shaft bearings are prone to fatigue wear and cracks under long-term high-load operation. This not only severely shortens the service life of the bearings but also frequently affects the normal operation of wind turbine generators. Ultimately, this is mainly due to the limitations of the performance of existing bearing materials and the imperfections in manufacturing processes, making it difficult for the bearings to effectively withstand complex loads. Summary of the Invention

[0003] The purpose of this invention is to provide a high-strength wind turbine main shaft bearing and its processing method. Through innovation across the entire chain of material selection, thermal processing, precision machining, surface strengthening, and assembly testing, the overall strength, fatigue resistance, wear resistance, and operational stability of the wind turbine main shaft bearing are systematically improved. This effectively meets the high-load and complex operating conditions required by the wind power industry, reduces the frequency of bearing replacement, lowers the operation and maintenance costs of wind turbine generator sets, and provides core component protection for the efficient and stable operation of wind power generation equipment.

[0004] To achieve the above objectives, the present invention provides the following technical solution: a processing method for a high-strength wind turbine main shaft bearing, the method comprising the following steps: S1. Raw material preparation: a. Raw material selection: High-strength alloy structural steel containing Cr, Ni, and Mo elements is selected as the bearing raw material, wherein the Cr element content is 1.5%-2.0%, the Ni element content is 0.8%-1.2%, and the Mo element content is 0.2%-0.5%; b. Pre-treatment of billet: The selected bearing billet is subjected to homogenization annealing at a temperature of 850-900℃ and a holding time of 4-6h. After being cooled in the furnace to below 300℃, it is removed from the furnace and air-cooled to eliminate segregation of the internal structure of the billet and ensure the uniformity of the material in subsequent processing. S2. Forging and shaping: The pretreated billet is heated to 1150-1200℃ and held for 2-3 hours before being forged in multiple passes. The deformation amount of each forging pass is controlled at 15%-25%. The final forging is a forging that matches the structure of the finished bearing. The grains are refined through multiple passes with small deformation forging, which improves the overall strength of the forging. S3. Quenching and tempering treatment: The forgings are quenched and tempered. First, the forgings are heated to 860-880℃ and held for 3-4 hours, then oil-cooled to room temperature, then heated to 580-620℃ and held for 5-6 hours, and air-cooled to room temperature to obtain a tempered sorbite structure with high strength and high toughness. S4. Precision machining: a. Inner and outer ring machining: The heat-treated inner and outer ring forgings are subjected to rough turning, semi-finish turning, finish turning and grinding in sequence to control the roundness error of the inner and outer ring raceways to be no greater than 0.005mm, the surface roughness Ra to be no greater than 0.8μm, and the parallelism error of the inner and outer ring end faces to be no greater than 0.003mm, so as to ensure the bearing assembly accuracy and operation stability. b. Rolling element processing: The tempered rolling element forgings are sequentially cold-headed, rough-grinded, semi-fine-grinded, and fine-grinded to control the spherical error of the rolling elements to be no greater than 0.002 mm, the surface roughness Ra to be no greater than 0.4 μm, and the diameter variation to be no greater than 0.001 mm, thereby reducing the concentration of contact stress during operation; S5. Surface strengthening treatment: a. Ion nitriding: The heat-treated bearing inner and outer rings and rolling elements are placed in an ion nitriding machine for surface strengthening treatment to improve surface wear resistance and fatigue strength. b. Hard chrome plating: Hard chrome plating is performed on the inner and outer rings and rolling elements of the bearing after ion nitriding to further enhance surface hardness and corrosion resistance; S6. Bearing Assembly and Inspection a. Bearing assembly: In an assembly workshop with a cleanliness level of not less than Class 8, use assembly equipment and tools with a coaxiality error of not more than 0.002mm to assemble parts such as inner and outer rings, rolling elements, and cages that have undergone machining and surface strengthening treatment; b. Finished product inspection: The assembled bearings are subjected to overall inspection, including dimensional accuracy inspection, rotational accuracy inspection, radial clearance inspection, surface hardness inspection and non-destructive testing. After passing the inspection, high-strength wind turbine main shaft bearings are obtained.

[0005] As a preferred embodiment, in step S1b, before homogenization annealing, the bearing blank needs to be surface derusted by sandblasting, with a sandblasting pressure of 0.4-0.6 MPa and a sand particle size of 80-120 mesh.

[0006] As a preferred embodiment, in step S2, during the multi-pass forging process, the billet temperature between two adjacent forging passes is maintained at 950-1100℃. If the temperature is lower than 950℃, it is reheated to 1150-1200℃ before the next forging pass.

[0007] As a preferred embodiment, in step S3, the hardness of the forging after quenching and tempering is 28-32 HRC, and the impact toughness Akv is not less than 60 J.

[0008] As a preferred embodiment, in step S4a, the inner and outer rings are ground using a cubic boron nitride grinding wheel with a grinding speed of 30-40 m / s and a feed rate of 0.005-0.01 mm / r.

[0009] As a preferred embodiment, in step S4b, the rolling element is precision ground using a diamond grinding wheel at a grinding speed of 25-35 m / s and a feed rate of 0.002-0.005 mm / r. The cold heading pressure is 800-1000 MPa, and after cold heading, stress-relief annealing is performed at a temperature of 350-400℃ and a holding time of 1-2 hours.

[0010] As a preferred embodiment, in step S5a, the nitriding temperature is 520-560℃ and the holding time is 15-20h, so that a nitrided layer with a thickness of 0.15-0.3mm and a hardness of HV850-1000 is formed on the inner and outer rings and rolling element surfaces of the bearing.

[0011] As a preferred embodiment, in step S5b, the CrO3 concentration in the plating solution is 220-250 g / L, the current density is 15-25 A / dm², and the electroplating time is 60-90 min, so that the chromium plating layer thickness is 0.01-0.03 mm and the surface roughness Ra is not greater than 0.2 μm.

[0012] As a preferred embodiment, in step S6a, the temperature of the assembly workshop is controlled at 20-24℃ and the relative humidity is controlled at 40%-60% to ensure the cleanliness and dimensional stability of the parts during the assembly process.

[0013] A high-strength wind turbine main shaft bearing is obtained by processing a high-strength wind turbine main shaft bearing.

[0014] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention uses high-strength alloy structural steel containing Cr, Ni, and Mo as the billet. Cr enhances wear resistance and hardenability, Ni strengthens toughness and fatigue resistance, and Mo improves high-temperature strength and tempering stability. This breaks through the performance bottleneck of traditional materials at the raw material level. Simultaneously, the homogenization annealing during the billet pretreatment stage effectively eliminates internal microstructure segregation, ensuring the uniformity of material composition and microstructure. This lays a stable material foundation for subsequent processing steps, avoiding localized stress concentration and early failure caused by material inhomogeneity.

[0015] This invention employs heating and multi-pass forging during the forging stage to effectively refine grains, significantly improving the overall strength and structural density of the forgings. Combined with subsequent tempering treatment, the forgings achieve a uniform tempered sorbite structure, balancing high strength and high toughness. This meets the strength requirements of wind turbine main shaft bearings under long-term high loads while preventing crack initiation and propagation during operation due to insufficient toughness. Furthermore, through multi-stage progressive processing and high-precision parameter control, not only are the dimensional and positional accuracy of each bearing component guaranteed, but the optimization of surface quality and geometric accuracy also reduces stress concentration at the contact point between rolling elements and raceways, lowering the local wear rate and significantly improving the stability and smoothness of bearing operation. This prevents increased vibration and abnormal wear caused by insufficient precision.

[0016] This invention employs a dual-layer surface strengthening process of ion nitriding and hard chrome plating to form an effective nitriding layer on the inner and outer rings and rolling elements of the bearing, significantly improving surface fatigue strength and wear resistance. Simultaneously, the subsequent hard chrome plating further enhances surface hardness and corrosion resistance. The synergistic effect of the dual-layer strengthening layer enables the bearing surface to possess multiple properties of high wear resistance, fatigue resistance, and corrosion resistance, effectively resisting the complex loads and harsh environmental erosion under wind power conditions, and significantly reducing the risk of fatigue wear and corrosion failure. Attached Figure Description

[0017] Figure 1 This is a flowchart of the method of the present invention. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that is mutually exclusive with other embodiments.

[0020] Example 1: This invention provides a method for processing high-strength wind turbine main shaft bearings, the method comprising the following steps: S1. Raw material preparation: a. Raw material selection: High-strength alloy structural steel containing Cr, Ni, and Mo elements is selected as the bearing raw material, wherein the Cr element content is 1.5%, the Ni element content is 0.8%, and the Mo element content is 0.2%; b. Billet pretreatment: The selected bearing billet is subjected to homogenization annealing at a temperature of 850℃ and a holding time of 4h. After being cooled in the furnace to below 300℃, it is removed from the furnace and air-cooled to eliminate segregation of the internal structure of the billet and ensure the uniformity of the material in subsequent processing. S2. Forging and shaping: The pretreated billet is heated to 1150℃ and held for 2 hours before being forged in multiple passes. The deformation amount of each forging pass is controlled at 15%. The final forging is a forging that matches the structure of the bearing product. The grains are refined through multiple passes with small deformation forging, which improves the overall strength of the forging. S3. Quenching and tempering treatment: The forgings are quenched and tempered. First, the forgings are heated to 860℃ and held for 3 hours, then oil-cooled to room temperature, then heated to 580℃ and held for 5 hours, and air-cooled to room temperature to obtain a tempered sorbite structure with high strength and high toughness. S4. Precision machining: a. Inner and outer ring machining: The heat-treated inner and outer ring forgings are subjected to rough turning, semi-finish turning, finish turning and grinding in sequence to control the roundness error of the inner and outer ring raceways to be no greater than 0.005mm, the surface roughness Ra to be no greater than 0.8μm, and the parallelism error of the inner and outer ring end faces to be no greater than 0.003mm, so as to ensure the bearing assembly accuracy and operation stability. b. Rolling element processing: The tempered rolling element forgings are sequentially cold-headed, rough-grinded, semi-fine-grinded, and fine-grinded to control the spherical error of the rolling elements to be no greater than 0.002 mm, the surface roughness Ra to be no greater than 0.4 μm, and the diameter variation to be no greater than 0.001 mm, thereby reducing the concentration of contact stress during operation; S5. Surface strengthening treatment: a. Ion nitriding: The heat-treated bearing inner and outer rings and rolling elements are placed in an ion nitriding machine for surface strengthening treatment to improve surface wear resistance and fatigue strength. b. Hard chrome plating: Hard chrome plating is performed on the inner and outer rings and rolling elements of the bearing after ion nitriding to further enhance surface hardness and corrosion resistance; S6. Bearing Assembly and Inspection a. Bearing assembly: In an assembly workshop with a cleanliness level of not less than Class 8, use assembly equipment and tools with a coaxiality error of not more than 0.002mm to assemble parts such as inner and outer rings, rolling elements, and cages that have undergone machining and surface strengthening treatment; b. Finished product inspection: The assembled bearings are subjected to overall inspection, including dimensional accuracy inspection, rotational accuracy inspection, radial clearance inspection, surface hardness inspection and non-destructive testing. After passing the inspection, high-strength wind turbine main shaft bearings are obtained.

[0021] In step S1b, before homogenization annealing, the bearing blank needs to be surface derusted by sandblasting with a pressure of 0.4 MPa and a particle size of 80 mesh.

[0022] In step S2, during the multi-pass forging process, the billet temperature between two adjacent forging passes is maintained at 950°C. If the temperature is lower than 950°C, it is reheated to 1150°C before the next forging pass.

[0023] In step S3, the hardness of the forging after quenching and tempering is 28 HRC, and the impact toughness Akv is not less than 60 J.

[0024] In step S4a, the inner and outer rings are ground using a cubic boron nitride grinding wheel at a grinding speed of 30 m / s and a feed rate of 0.005 mm / r.

[0025] In step S4b, the rolling element is precision ground using a diamond grinding wheel at a grinding speed of 25 m / s and a feed rate of 0.002 mm / r. The cold heading pressure is 800 MPa. After cold heading, stress-relieving annealing is performed at a temperature of 350°C and a holding time of 1 hour.

[0026] In step S5a, the nitriding temperature is 520℃ and the holding time is 15h, so that a nitrided layer with a thickness of 0.15mm and a hardness of HV850 is formed on the inner and outer rings and rolling element surfaces of the bearing.

[0027] In step S5b, the CrO3 concentration in the plating solution is 220 g / L, the current density is 15 A / dm², and the electroplating time is 60 min, so that the chromium plating layer thickness is 0.01 mm and the surface roughness Ra is not greater than 0.2 μm.

[0028] In step S6a, the temperature in the assembly workshop is controlled at 20°C and the relative humidity is controlled at 40% to ensure the cleanliness and dimensional stability of the parts during the assembly process.

[0029] A high-strength wind turbine main shaft bearing is obtained by processing a high-strength wind turbine main shaft bearing.

[0030] Example 2: This invention provides a method for processing a high-strength wind turbine main shaft bearing, the method comprising the following steps: S1. Raw material preparation: a. Raw material selection: High-strength alloy structural steel containing Cr, Ni, and Mo elements is selected as the bearing raw material, wherein the Cr element content is 1.75%, the Ni element content is 1%, and the Mo element content is 0.35%; b. Billet pretreatment: The selected bearing billet is subjected to homogenization annealing at a temperature of 875℃ and a holding time of 5h. After being cooled in the furnace to below 300℃, it is removed from the furnace and air-cooled to eliminate segregation of the internal structure of the billet and ensure the uniformity of the material in subsequent processing. S2. Forging and forming: The pretreated billet is heated to 1175℃ and held for 2.5h before being forged in multiple passes. The deformation amount of each forging is controlled at 20%. Finally, the forging is made into a forging that matches the structure of the finished bearing. The grains are refined by forging with small deformation in multiple passes, which improves the overall strength of the forging. S3. Quenching and tempering treatment: The forgings are quenched and tempered by first heating them to 870℃ and holding them for 3.5 hours, then oil cooling them to room temperature, then heating them to 600℃ and holding them for 5.5 hours, and finally air cooling them to room temperature to obtain a tempered sorbite structure with high strength and high toughness. S4. Precision machining: a. Inner and outer ring machining: The heat-treated inner and outer ring forgings are subjected to rough turning, semi-finish turning, finish turning and grinding in sequence to control the roundness error of the inner and outer ring raceways to be no greater than 0.005mm, the surface roughness Ra to be no greater than 0.8μm, and the parallelism error of the inner and outer ring end faces to be no greater than 0.003mm, so as to ensure the bearing assembly accuracy and operation stability. b. Rolling element processing: The tempered rolling element forgings are sequentially cold-headed, rough-grinded, semi-fine-grinded, and fine-grinded to control the spherical error of the rolling elements to be no greater than 0.002 mm, the surface roughness Ra to be no greater than 0.4 μm, and the diameter variation to be no greater than 0.001 mm, thereby reducing the concentration of contact stress during operation; S5. Surface strengthening treatment: a. Ion nitriding: The heat-treated bearing inner and outer rings and rolling elements are placed in an ion nitriding machine for surface strengthening treatment to improve surface wear resistance and fatigue strength. b. Hard chrome plating: Hard chrome plating is performed on the inner and outer rings and rolling elements of the bearing after ion nitriding to further enhance surface hardness and corrosion resistance; S6. Bearing Assembly and Inspection a. Bearing assembly: In an assembly workshop with a cleanliness level of not less than Class 8, use assembly equipment and tools with a coaxiality error of not more than 0.002mm to assemble parts such as inner and outer rings, rolling elements, and cages that have undergone machining and surface strengthening treatment; b. Finished product inspection: The assembled bearings are subjected to overall inspection, including dimensional accuracy inspection, rotational accuracy inspection, radial clearance inspection, surface hardness inspection and non-destructive testing. After passing the inspection, high-strength wind turbine main shaft bearings are obtained.

[0031] In step S1b, before homogenization annealing, the bearing blank needs to be surface derusted by sandblasting with a pressure of 0.5 MPa and a particle size of 100 mesh.

[0032] In step S2, during the multi-pass forging process, the billet temperature between two adjacent forging passes is maintained at 1025°C. If the temperature is lower than 950°C, it is reheated to 1175°C before the next forging pass.

[0033] In step S3, the hardness of the forging after quenching and tempering is 30 HRC, and the impact toughness Akv is not less than 60 J.

[0034] In step S4a, the inner and outer rings are ground using a cubic boron nitride grinding wheel at a grinding speed of 35 m / s and a feed rate of 0.0075 mm / r.

[0035] In step S4b, the rolling element is precision ground using a diamond grinding wheel at a grinding speed of 30 m / s and a feed rate of 0.0035 mm / r. The cold heading pressure is 900 MPa. After cold heading, stress-relief annealing is performed at a temperature of 375°C and a holding time of 1.5 h.

[0036] In step S5a, the nitriding temperature is 540℃ and the holding time is 17.5h, so that a nitrided layer with a thickness of 0.225mm and a hardness of HV925 is formed on the inner and outer rings and rolling element surfaces of the bearing.

[0037] In step S5b, the CrO3 concentration in the plating solution is 235 g / L, the current density is 20 A / dm², and the electroplating time is 75 min, so that the chromium plating layer thickness is 0.02 mm and the surface roughness Ra is not greater than 0.2 μm.

[0038] In step S6a, the temperature in the assembly workshop is controlled at 22°C and the relative humidity is controlled at 50% to ensure the cleanliness and dimensional stability of the parts during the assembly process.

[0039] A high-strength wind turbine main shaft bearing is obtained by processing a high-strength wind turbine main shaft bearing.

[0040] Example 3: This invention provides a method for processing a high-strength wind turbine main shaft bearing, the method comprising the following steps: S1. Raw material preparation: a. Raw material selection: High-strength alloy structural steel containing Cr, Ni, and Mo elements is selected as the bearing raw material, wherein the Cr element content is 2.0%, the Ni element content is 1.2%, and the Mo element content is 0.5%; b. Billet pretreatment: The selected bearing billet is subjected to homogenization annealing at a temperature of 900℃ and a holding time of 6h. After being cooled in the furnace to below 300℃, it is removed from the furnace and air-cooled to eliminate segregation of the internal structure of the billet and ensure the uniformity of the material in subsequent processing. S2. Forging and shaping: The pretreated billet is heated to 1200℃ and held for 3 hours before being forged in multiple passes. The deformation amount of each forging pass is controlled at 25%. The final forging is a forging that matches the structure of the finished bearing. The grains are refined through multiple passes with small deformation forging, which improves the overall strength of the forging. S3. Quenching and tempering treatment: The forgings are quenched and tempered. First, the forgings are heated to 880℃ and held for 4 hours, then oil-cooled to room temperature, then heated to 620℃ and held for 6 hours, and air-cooled to room temperature to obtain a tempered sorbite structure with high strength and high toughness. S4. Precision machining: a. Inner and outer ring machining: The heat-treated inner and outer ring forgings are subjected to rough turning, semi-finish turning, finish turning and grinding in sequence to control the roundness error of the inner and outer ring raceways to be no greater than 0.005mm, the surface roughness Ra to be no greater than 0.8μm, and the parallelism error of the inner and outer ring end faces to be no greater than 0.003mm, so as to ensure the bearing assembly accuracy and operation stability. b. Rolling element processing: The tempered rolling element forgings are sequentially cold-headed, rough-grinded, semi-fine-grinded, and fine-grinded to control the spherical error of the rolling elements to be no greater than 0.002 mm, the surface roughness Ra to be no greater than 0.4 μm, and the diameter variation to be no greater than 0.001 mm, thereby reducing the concentration of contact stress during operation; S5. Surface strengthening treatment: a. Ion nitriding: The heat-treated bearing inner and outer rings and rolling elements are placed in an ion nitriding machine for surface strengthening treatment to improve surface wear resistance and fatigue strength. b. Hard chrome plating: Hard chrome plating is performed on the inner and outer rings and rolling elements of the bearing after ion nitriding to further enhance surface hardness and corrosion resistance; S6. Bearing Assembly and Inspection a. Bearing assembly: In an assembly workshop with a cleanliness level of not less than Class 8, use assembly equipment and tools with a coaxiality error of not more than 0.002mm to assemble parts such as inner and outer rings, rolling elements, and cages that have undergone machining and surface strengthening treatment; b. Finished product inspection: The assembled bearings are subjected to overall inspection, including dimensional accuracy inspection, rotational accuracy inspection, radial clearance inspection, surface hardness inspection and non-destructive testing. After passing the inspection, high-strength wind turbine main shaft bearings are obtained.

[0041] In step S1b, before homogenization annealing, the bearing blank needs to be surface derusted by sandblasting with a pressure of 0.6 MPa and a particle size of 120 mesh.

[0042] In step S2, during the multi-pass forging process, the billet temperature between two adjacent forging passes is maintained at 1100℃. If the temperature is lower than 950℃, it is reheated to 1200℃ before the next forging pass.

[0043] In step S3, the hardness of the forging after quenching and tempering is 32HRC, and the impact toughness Akv is not less than 60J.

[0044] In step S4a, the inner and outer rings are ground using a cubic boron nitride grinding wheel at a grinding speed of 40 m / s and a feed rate of 0.01 mm / r.

[0045] In step S4b, the rolling element is precision ground using a diamond grinding wheel at a grinding speed of 35 m / s and a feed rate of 0.005 mm / r. The cold heading pressure is 1000 MPa. After cold heading, stress-relief annealing is performed at a temperature of 400℃ and a holding time of 2 hours.

[0046] In step S5a, the nitriding temperature is 560℃ and the holding time is 20h, so that a nitrided layer with a thickness of 0.3mm and a hardness of HV1000 is formed on the inner and outer rings and rolling element surfaces of the bearing.

[0047] In step S5b, the CrO3 concentration in the plating solution is 250 g / L, the current density is 25 A / dm², and the electroplating time is 90 min, so that the chromium plating layer thickness is 0.03 mm and the surface roughness Ra is not greater than 0.2 μm.

[0048] In step S6a, the temperature in the assembly workshop is controlled at 24°C and the relative humidity is controlled at 60% to ensure the cleanliness and dimensional stability of the parts during the assembly process.

[0049] A high-strength wind turbine main shaft bearing is obtained by processing a high-strength wind turbine main shaft bearing.

[0050] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A method for processing a high-strength wind turbine main shaft bearing, characterized in that, The method includes the following steps: S1. Raw material preparation: a. Raw material selection: High-strength alloy structural steel containing Cr, Ni, and Mo elements is selected as the bearing raw material, wherein the Cr element content is 1.5%-2.0%, the Ni element content is 0.8%-1.2%, and the Mo element content is 0.2%-0.5%; b. Pre-treatment of billet: The selected bearing billet is subjected to homogenization annealing at a temperature of 850-900℃ and a holding time of 4-6h. After being cooled in the furnace to below 300℃, it is removed from the furnace and air-cooled to eliminate segregation of the internal structure of the billet and ensure the uniformity of the material in subsequent processing. S2. Forging and shaping: The pretreated billet is heated to 1150-1200℃ and held for 2-3 hours before being forged in multiple passes. The deformation amount of each forging pass is controlled at 15%-25%. The final forging is a forging that matches the structure of the finished bearing. The grains are refined through multiple passes with small deformation forging, which improves the overall strength of the forging. S3. Quenching and tempering treatment: The forgings are quenched and tempered. First, the forgings are heated to 860-880℃ and held for 3-4 hours, then oil-cooled to room temperature, then heated to 580-620℃ and held for 5-6 hours, and air-cooled to room temperature to obtain a tempered sorbite structure with high strength and high toughness. S4. Precision machining: a. Inner and outer ring machining: The heat-treated inner and outer ring forgings are subjected to rough turning, semi-finish turning, finish turning and grinding in sequence to control the roundness error of the inner and outer ring raceways to be no greater than 0.005mm, the surface roughness Ra to be no greater than 0.8μm, and the parallelism error of the inner and outer ring end faces to be no greater than 0.003mm, so as to ensure the bearing assembly accuracy and operation stability. b. Rolling element processing: The tempered rolling element forgings are sequentially cold-headed, rough-grinded, semi-fine-grinded, and fine-grinded to control the spherical error of the rolling elements to be no greater than 0.002 mm, the surface roughness Ra to be no greater than 0.4 μm, and the diameter variation to be no greater than 0.001 mm, thereby reducing the concentration of contact stress during operation; S5. Surface strengthening treatment: a. Ion nitriding: The heat-treated bearing inner and outer rings and rolling elements are placed in an ion nitriding machine for surface strengthening treatment to improve surface wear resistance and fatigue strength. b. Hard chrome plating: Hard chrome plating is performed on the inner and outer rings and rolling elements of the bearing after ion nitriding to further enhance surface hardness and corrosion resistance; S6. Bearing Assembly and Inspection a. Bearing assembly: In an assembly workshop with a cleanliness level of not less than Class 8, use assembly equipment and tools with a coaxiality error of not more than 0.002mm to assemble parts such as inner and outer rings, rolling elements, and cages that have undergone machining and surface strengthening treatment; b. Finished product inspection: The assembled bearings are subjected to overall inspection, including dimensional accuracy inspection, rotational accuracy inspection, radial clearance inspection, surface hardness inspection and non-destructive testing. After passing the inspection, high-strength wind turbine main shaft bearings are obtained.

2. The processing method of a high-strength wind turbine main shaft bearing according to claim 1, characterized in that: In step S1b, before homogenization annealing, the bearing blank needs to be surface derusted by sandblasting with a pressure of 0.4-0.6 MPa and a particle size of 80-120 mesh.

3. The processing method of a high-strength wind turbine main shaft bearing according to claim 1, characterized in that: In step S2, during the multi-pass forging process, the billet temperature between two adjacent forging passes is maintained at 950-1100℃. If the temperature is lower than 950℃, it is reheated to 1150-1200℃ before the next forging pass.

4. The processing method of a high-strength wind turbine main shaft bearing according to claim 1, characterized in that: In step S3, the hardness of the forging after quenching and tempering is 28-32 HRC, and the impact toughness Akv is not less than 60 J.

5. The processing method of a high-strength wind turbine main shaft bearing according to claim 1, characterized in that: In step S4a, the inner and outer rings are ground using a cubic boron nitride grinding wheel at a grinding speed of 30-40 m / s and a feed rate of 0.005-0.01 mm / r.

6. The processing method of a high-strength wind turbine main shaft bearing according to claim 1, characterized in that: In step S4b, the rolling element is precision ground using a diamond grinding wheel at a grinding speed of 25-35 m / s and a feed rate of 0.002-0.005 mm / r. The cold heading pressure is 800-1000 MPa. After cold heading, stress-relief annealing is performed at a temperature of 350-400℃ and a holding time of 1-2 hours.

7. The processing method of a high-strength wind turbine main shaft bearing according to claim 1, characterized in that: In step S5a, the nitriding temperature is 520-560℃ and the holding time is 15-20h, so that a nitrided layer with a thickness of 0.15-0.3mm and a hardness of HV850-1000 is formed on the inner and outer rings and rolling element surfaces of the bearing.

8. The processing method of a high-strength wind turbine main shaft bearing according to claim 1, characterized in that: In step S5b, the CrO3 concentration in the plating solution is 220-250 g / L, the current density is 15-25 A / dm², and the electroplating time is 60-90 min, so that the chromium plating layer thickness is 0.01-0.03 mm and the surface roughness Ra is not greater than 0.2 μm.

9. The processing method of a high-strength wind turbine main shaft bearing according to claim 1, characterized in that: In step S6a, the temperature in the assembly workshop is controlled at 20-24℃ and the relative humidity is controlled at 40%-60% to ensure the cleanliness and dimensional stability of the parts during the assembly process.

10. A high-strength wind turbine main shaft bearing, manufactured by the processing method of any one of claims 1-9.

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