Bearing retainer machining process

Abstract

The invention discloses a bearing retainer machining process which comprises a pocket plunge milling mode and a pocket turning mode and belongs to the technical field of bearing part machining. According to the technology, the pocket machining precision, stability and production efficiency are effectively improved by optimizing pocket plunge milling and turning process parameters and technical management and control according to key machining links of a centrifugal tube material bearing retainer with the diameter of 1-1200 mm and focusing pockets. According to the pocket plunge milling mode, pockets are formed through layered efficient turning, the pocket size precision is guaranteed through precise turning in the pocket turning mode, roundness deformation can be strictly controlled through the two technologies, the contour precision and the pocket precision are guaranteed, and the quality consistency of products with different diameter specifications is improved.

Description

Technical Field

[0001] This invention relates to the field of bearing component processing technology, and in particular to a bearing retainer processing technology. Background Technology

[0002] The pocket in a bearing retainer is a critical functional component, and its machining accuracy directly affects the bearing's assembly performance and service life. Traditional pocket machining suffers from insufficient process specificity and poor accuracy stability, making it difficult to adapt to the machining requirements of products with different diameters. Pocket milling offers high-efficiency forming advantages, while pocket turning ensures dimensional accuracy through precise turning; however, existing technologies lack systematic specifications for both processes. This invention aims to provide two standardized process solutions focusing on pocket machining, improving the machining quality and efficiency of retainers with different diameters. Summary of the Invention

[0003] This invention provides two bearing retainer machining processes: pocket milling and pocket turning. For diameters ranging from 1 to 1200 mm, the invention improves the accuracy and efficiency of pocket machining by clarifying the key processes, parameters, and control requirements of pocket machining.

[0004] A bearing retainer machining process includes a broaching bearing retainer machining process, a milling bearing retainer machining process, and a turning bearing retainer machining process.

[0005] (1) The machining process of the bearing retainer in the broaching mode is as follows:

[0006] Step S1: Material preparation and incoming material inspection

[0007] Centrifugal tubing is used for material preparation using Dahe machine tools to obtain blanks of corresponding specifications for bearing retainers with diameters ranging from 1 to 1200 mm. A three-piece integrated clamping method is adopted, with a clamping distance of 20 mm for diameters ≤ 500 mm and 30-50 mm for diameters > 500 mm. The total length and inner and outer diameter allowances are measured using vernier calipers, and the material composition is inspected using a metallographic analyzer and compared with the factory composition to ensure material qualification.

[0008] Step S2: Material aging treatment

[0009] The aging treatment of the material was completed within 48 hours, specifically a high-temperature treatment of 120℃ for 8 hours and a low-temperature treatment of -20℃ for 16 hours, in order to stabilize the material properties.

[0010] Step S3: Molding Process

[0011] First, the inner and outer diameters are shaped using a Mazak machine tool to achieve a roundness tolerance of 0.005mm or 0.01mm.

[0012] Subsequently, a quick 4-axis machining center was used for roughing the pocket using a planing method, with TC4 carbide tools selected. The cutting speed was 90 m / min or 70-80 m / min, and the feed rate was 0.12 mm / r or 0.08-0.1 mm / r. The axial feed depth of the tool was 2-3 mm / stroke for diameters ≤ 500 mm and 1-2 mm / stroke for diameters > 500 mm. A finishing allowance was reserved for the pocket: 0.2 mm for diameters ≤ 500 mm and 0.3 mm for diameters > 500 mm.

[0013] Finally, the hole was precision shaped by inserting and shaping using a Yasuda 5-axis machining center. W18Cr4V high-speed steel tools were used, with a cutting speed of 130 m / min or 100-120 m / min and a feed rate of 0.06 mm / r or 0.04-0.05 mm / r. A layered inserting strategy was employed: for diameters ≤ 500 mm, the depth of cut per layer was 0.05-0.1 mm; for diameters > 500 mm, the depth of cut per layer was 0.03-0.08 mm, resulting in a surface roughness of Ra ≤ 1.6 μm or Ra ≤ 3.2 μm for the hole.

[0014] Step S4: Detection and Calibration

[0015] The contour accuracy and pocket R-value of the first piece are measured using a three-dimensional measuring machine. The allowable tolerance for contour accuracy is 0.003mm or 0.005mm, and the allowable tolerance for pocket R-value is 0.002mm or 0.003mm. Two first pieces are calibrated for each batch. The cutting tools are checked when processing 50 or 30 pieces in batch, and the cutting tools are replaced when processing 200 or 150 pieces or when quality abnormalities occur.

[0016] Step S5: Post-processing

[0017] Remove burrs with a copper wire brush, clean with ultrasonic cleaner, apply oil, then pack with kraft paper gloves and place in layers.

[0018] (2) The milling process for bearing retainers is as follows:

[0019] Step M1: Material preparation and incoming material inspection

[0020] The same step S1 as the cutting mode ensures that the billet specifications and quality meet the requirements;

[0021] Step M2: Material Aging Treatment

[0022] In step S2 of the same planing mode, the material properties are stabilized through high and low temperature treatment;

[0023] Step M3: Molding Process

[0024] The inner and outer diameters of the bearing retainer are milled using a high-precision milling machine to ensure that the roundness tolerance is ≤0.006mm;

[0025] For rough machining of the pocket, use a special milling cutter for rough milling. Select appropriate parameters according to the diameter of the bearing retainer: when the diameter is ≤500mm, the milling speed is 80-100m / min and the feed rate is 0.1-0.15mm / r; when the diameter is >500mm, the milling speed is 60-80m / min and the feed rate is 0.08-0.12mm / r.

[0026] The finishing of the pocket is carried out using a CNC milling machine with a high-performance carbide end mill. When the diameter is ≤500mm, the milling speed is 120-140m / min and the feed rate is 0.05-0.08mm / r; when the diameter is >500mm, the milling speed is 100-120m / min and the feed rate is 0.04-0.06mm / r, to ensure the accuracy and surface quality of the pocket.

[0027] Step M4: Detection and Calibration

[0028] The contour accuracy, pocket size, and positional accuracy of the first piece are inspected using a three-dimensional measuring instrument. The allowable tolerance for contour accuracy is 0.004mm, the allowable tolerance for pocket size is ±0.003mm, and the allowable tolerance for positional accuracy is ≤0.005mm. The first piece calibration quantity for each batch is 2 pieces. The cutting tool is inspected when 40 pieces are processed in a batch, and the cutting tool is replaced when 180 pieces are processed or when quality problems occur.

[0029] Step M5: Post-processing

[0030] First, deburr the material, then clean it with a special cleaning agent, then apply rust prevention treatment, and finally package it in a special packaging box.

[0031] (3) The machining process for bearing retainers in turning mode is as follows:

[0032] (3.1) Conventional turning method

[0033] Step a: Material preparation and incoming material inspection

[0034] Same as step S1 in the insertion and cutting mode;

[0035] Step b: Material aging treatment

[0036] Step S2 of the same insertion and cutting mode;

[0037] Step c: Molding and processing

[0038] The inner and outer diameters are formed by turning on a Mazak machine tool, so that the roundness tolerance can reach 0.005mm or 0.01mm;

[0039] Use CNC4 to pre-form the pocket. When the diameter is ≤500mm, leave 0.1-0.15mm on one side; when the diameter is >500mm, leave 0.15-0.2mm on one side.

[0040] The pocket finishing process is performed on a CNC5 machine using a carbide cutting tool at a turning speed of 150-200 m / min or 100-150 m / min and a feed rate of 0.08-0.12 mm / r or 0.06-0.09 mm / r. Before finishing the pocket, the accuracy of the pocket reference surface must be ensured by turning. For diameters > 500 mm, an additional turning process for the pocket positioning surface is added, with a flatness tolerance of ≤ 0.01 mm and radial runout of ≤ 0.005 mm. At the same time, the pocket turning adopts a circular interpolation turning strategy: single-edge turning is used for diameters ≤ 500 mm, and multi-edge segmented turning is used for diameters > 500 mm, with each segment having an arc length of ≤ 100 mm. After turning, the R-value deviation of the pocket is ≤ 0.003 mm.

[0041] Step d: Detection and calibration

[0042] The allowable tolerance for the contour accuracy of the first piece measured by three-dimensional coordinate measuring machine is 0.003mm or 0.005mm, and the allowable tolerance for the R value of the pocket is 0.002mm or 0.003mm. The first piece of each batch of 2 pieces is calibrated. When processing 40 pieces or 20-30 pieces in batch, check the tool. When processing 150 pieces or 100-120 pieces or when the quality is abnormal, replace the tool.

[0043] Step e: Post-processing

[0044] Step S5 of the same insertion and cutting mode;

[0045] (3.2) High-efficiency precision turning method

[0046] Step A: Material preparation and incoming material inspection

[0047] Based on step S1, eddy current testing is added to check for internal defects in blanks with a diameter > 800 mm to ensure that there are no defects such as cracks or inclusions that affect processing performance.

[0048] Step B: Material Aging Treatment

[0049] Based on step S2, for high-strength alloy materials, a medium-temperature tempering treatment of 200℃×4 hours is added to further stabilize the metallographic structure of the material and improve the uniformity of the material hardness.

[0050] Step C: Molding Processing

[0051] The inner and outer diameters are turned simultaneously using a dual-spindle linkage lathe, achieving a roundness tolerance of 0.004mm, which is 20% more accurate than the traditional method.

[0052] Specialized CNC lathes are used for pre-forming of the pockets. For diameters ≤500mm, a single-sided allowance of 0.08-0.12mm is provided, and for diameters >500mm, a single-sided allowance of 0.12-0.18mm is provided, resulting in more precise allowances.

[0053] High-precision CNC lathe for pocket turning, using ultra-fine grain carbide cutting tools, turning speed 220-280m / min, feed rate 0.05-0.1mm / r, with cutting fluid constant temperature control system, temperature is controlled at 20±2℃, reducing the impact of thermal deformation on machining accuracy;

[0054] In addition, the precision turning of the pocket adopts an adaptive feed adjustment system, which automatically adjusts the feed rate within the range of 50-150N based on the real-time detected changes in cutting force. When the cutting force exceeds 150N, the feed rate is automatically reduced by 10%-15%, and when the cutting force is below 50N, the feed rate is automatically increased by 5%-10% to ensure a balance between machining efficiency and surface quality. For bearing retainers with a diameter >1000mm, a split turning fixture is used to divide the workpiece into 3-4 fan-shaped areas for step-by-step turning. After each area is turned, the splicing accuracy is checked, and the allowable gap tolerance at the splicing point is ≤0.003mm to ensure the machining accuracy of large workpieces.

[0055] Step D: Detection and Calibration

[0056] In addition to the inspection content in step d, a laser interferometer is added to check the position of the pocket, with a tolerance of ≤0.002mm; 5 sampling inspections are added to the first piece of each batch to cover pockets in different positions; the tool is checked when 30 or 15-25 pieces are processed in batches, and the tool is replaced when 120 or 80-100 pieces are processed or when the quality is abnormal. The tool replacement frequency is higher to ensure processing stability.

[0057] Step E: Post-processing

[0058] Based on step S5, a precision grinding process is added to grind the edge of the pocket with a precision of 0.005mm, further reducing the surface roughness to Ra≤0.8μm.

[0059] Furthermore, in step S3, the axial feed depth of the tool during rough milling of the pocket is 2-3 mm / time for diameters ≤ 500 mm and 1-2 mm / time for diameters > 500 mm; a finishing milling allowance of 0.2 mm for pockets with diameters ≤ 500 mm or 0.3 mm for pockets with diameters > 500 mm is reserved.

[0060] Furthermore, in step S3, a layered milling strategy is adopted when milling the pocket: for diameters ≤ 500mm, the cutting depth of each layer is 0.05-0.1mm; for diameters > 500mm, the cutting depth of each layer is 0.03-0.08mm; and the surface roughness of the pocket Ra is ≤ 1.6μm or Ra ≤ 3.2μm.

[0061] Furthermore, in step c, before precision turning of the pocket, the accuracy of the pocket reference surface needs to be ensured by turning. When the diameter is > 500 mm, a turning process for the pocket positioning surface is added. The flatness tolerance is ≤ 0.01 mm and the radial runout is ≤ 0.005 mm.

[0062] Furthermore, in step c, the pocket turning adopts a circular interpolation turning strategy: for diameters ≤500mm, single-edge turning is used; for diameters >500mm, multi-edge segmented turning is used, with each segment having an arc length ≤100mm, and the deviation of the pocket R value after turning is ≤0.003mm.

[0063] The beneficial effects of this invention are as follows:

[0064] 1. Highly targeted processing: For bearing retainers of different diameters (1-1200mm), different processing parameters are set for three modes: planing, milling, and turning. These parameters include cutting speed, feed rate, depth of cut, and allowance, ensuring that each diameter retainer can be processed with a suitable process, thus improving the accuracy of the machining.

[0065] 2. High precision and stability: Through strict material aging treatment processes, including high-temperature, low-temperature, and medium-temperature tempering, the material properties and metallographic structure are stabilized, reducing deformation during processing. In the inspection and correction stage, reasonable first-piece inspection quantities, tool inspection and replacement cycles are set. In particular, laser interferometer inspection and multi-point sampling inspection are added to the high-efficiency precision turning method, which can promptly detect and correct processing errors, ensuring the stability of product precision.

[0066] 3. Improved machining quality: Appropriate tool materials and types were selected for different process modes, such as TC4 carbide tools, W18Cr4V high-speed steel tools, high-performance carbide end mills, and ultra-fine grain carbide turning tools. Advanced machining strategies were also adopted, such as layered planing, circular interpolation turning, adaptive feed adjustment, and split turning fixtures, which effectively improved the dimensional accuracy, shape accuracy, positional accuracy, and surface quality of the pockets. The surface roughness can reach Ra≤0.8μm.

[0067] 4. Optimized machining efficiency: The high-efficiency forming advantage of the planing mode, the reasonable parameter settings of the milling mode, and the dual-spindle linkage turning and adaptive feed adjustment technologies in the turning mode improve machining efficiency while ensuring machining quality. At the same time, the precise allowance setting reduces the workload of subsequent machining, further improving the overall machining efficiency.

[0068] 5. Wide range of applications: It covers three machining modes: planing, milling and turning. The turning mode includes two methods: conventional turning and high-efficiency precision turning. It can meet the machining of bearing retainers with different production needs and different precision requirements. It is suitable for machining bearing retainers with various diameter specifications and material types. Attached Figure Description

[0069] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0070] Figure 1 This is a schematic diagram of the bearing retainer structure of the present invention;

[0071] Figure 2 This is a side view of the bearing retainer structure;

[0072] Figure 3 for Figure 2 Enlarged radial projection view of the relief groove in the middle I section.

[0073] In the diagram: 1-bearing retainer, 2-pocket. Detailed Implementation

[0074] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, 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. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0075] (I) Hole Milling Process

[0076] Step S1: Material preparation and incoming material inspection

[0077] Centrifugal tubing is used, and Dahe Machine Tool prepares the materials: blanks with diameters of 1-500mm are machined to the corresponding specifications; blanks with diameters of 501-1200mm have an added rigid support structure. A 3-piece integrated clamping system is used: 20mm clamping space for diameters ≤500mm, and 30-50mm clamping space for diameters >500mm (increasing the clamping space by 10mm for every 200mm increase in diameter). The total length is checked with vernier calipers (tolerance ±1mm), with inner diameter allowances of 2mm for diameters ≤500mm and 3-5mm for diameters >500mm, and outer diameter allowances of 2.5mm for diameters ≤500mm and 3-6mm for diameters >500mm. The composition is checked using a metallographic analyzer and compared with the factory report to ensure Al% 9-11%, Fe% 2-4%, and Mn% 1-2%.

[0078] Step S2: Material aging treatment

[0079] The billet is placed in a heating machine and a freezer, and undergoes a high-temperature cycle of 120℃ for 8 hours and a low-temperature cycle of -20℃ for 16 hours within 48 hours. For diameters > 500mm, an additional temperature cycle is added (6 hours of high temperature + 12 hours of low temperature) to release internal stress, stabilize the material structure, and reduce deformation after hole processing.

[0080] Step S3: Molding Process

[0081] Mazak machine tool inner and outer diameter forming: for diameters ≤500mm, the roundness tolerance is 0.005mm; for diameters >500mm, the roundness tolerance is 0.01mm. Verified by a roundness tester, it provides a precise benchmark for hole processing.

[0082] For roughing and milling of holes in a 4-axis machining center: For diameters ≤500mm, use TC4 carbide tools, cutting speed 80-100m / min, feed rate 0.08-0.12mm / r, axial feed depth 2-3mm / pass, with a 0.2mm finish milling allowance; For diameters >500mm, use reinforced TC4 tools, cutting speed 70-80m / min, feed rate 0.08-0.1mm / r, axial feed depth 1-2mm / pass, with a 0.3mm finish milling allowance.

[0083] Yasuda 5-axis machining center pocket milling precision forming: For diameters ≤500mm, use W18Cr4V high-speed steel tools, cutting speed 110-130m / min, feed rate 0.05-0.07mm / r, layer milling 0.05-0.1mm per layer; For diameters >500mm, use coated W18Cr4V tools, cutting speed 100-120m / min, feed rate 0.04-0.05mm / r, layer milling 0.03-0.08mm per layer, ensuring pocket surface roughness Ra≤1.6μm (diameter ≤500mm) or Ra≤3.2μm (diameter >500mm).

[0084] Step S4: Detection and Calibration

[0085] Roundness tester and 3D coordinate measuring machine (CMM) inspection of the first piece: For diameters ≤ 500mm, the allowable tolerance for contour accuracy is 0.003mm, and the allowable tolerance for pocket radius (R) is 0.002mm; for diameters > 500mm, the allowable tolerance for contour accuracy is 0.005mm, and the allowable tolerance for pocket radius (R) is 0.003mm. After the first two pieces pass calibration for each batch, mass production begins. During batch processing, for diameters ≤ 500mm, tool wear is checked every 50 pieces, and the tool is replaced after a cumulative total of 200 pieces; for diameters > 500mm, the tool is checked every 30 pieces, and the tool is replaced after a cumulative total of 150 pieces. The tool is replaced immediately if surface quality deteriorates or dimensional deviations occur.

[0086] Step S5: Post-processing

[0087] For diameters ≤500mm, use a copper wire brush to remove burrs from the edges of the pockets. For diameters >500mm, use a pneumatic tool to assist in deburring. Visually inspect for burrs and sharp edges. Ultrasonic cleaning: for diameters ≤500mm, use 500W power for 5 minutes; for diameters >500mm, use 800-1200W power for 8-12 minutes. Apply anti-rust oil afterwards. Pack in kraft paper. For diameters >500mm, use reinforced wooden crates. Wear powder-free latex gloves during handling. Place batches in layers with partitions to prevent crushing.

[0088] (II) Hole-cutting turning process

[0089] Step M1: Material preparation and incoming material inspection

[0090] The same step S1 as the cutting mode ensures that the billet specifications and quality meet the requirements;

[0091] Step M2: Material Aging Treatment

[0092] In step S2 of the same planing mode, the material properties are stabilized through high and low temperature treatment;

[0093] Step M3: Molding Process

[0094] The inner and outer diameters of the bearing retainer are milled using a high-precision milling machine to ensure that the roundness tolerance is ≤0.006mm;

[0095] For rough machining of the pocket, use a special milling cutter for rough milling. Select appropriate parameters according to the diameter of the bearing retainer: when the diameter is ≤500mm, the milling speed is 80-100m / min and the feed rate is 0.1-0.15mm / r; when the diameter is >500mm, the milling speed is 60-80m / min and the feed rate is 0.08-0.12mm / r.

[0096] The finishing of the pocket is carried out using a CNC milling machine with a high-performance carbide end mill. When the diameter is ≤500mm, the milling speed is 120-140m / min and the feed rate is 0.05-0.08mm / r; when the diameter is >500mm, the milling speed is 100-120m / min and the feed rate is 0.04-0.06mm / r, to ensure the accuracy and surface quality of the pocket.

[0097] Step M4: Detection and Calibration

[0098] The contour accuracy, pocket size, and positional accuracy of the first piece are inspected using a three-dimensional measuring instrument. The allowable tolerance for contour accuracy is 0.004mm, the allowable tolerance for pocket size is ±0.003mm, and the allowable tolerance for positional accuracy is ≤0.005mm. The first piece calibration quantity for each batch is 2 pieces. The cutting tool is inspected when 40 pieces are processed in a batch, and the cutting tool is replaced when 180 pieces are processed or when quality problems occur.

[0099] Step M5: Post-processing

[0100] First, deburr the material, then clean it with a special cleaning agent, then apply rust prevention treatment, and finally package it in a special packaging box.

[0101] (III) Machining process of bearing retainers by turning

[0102] (3.1) Conventional turning method

[0103] Step a: Material preparation and incoming material inspection

[0104] Same as step S1 in the insertion and cutting mode;

[0105] Step b: Material aging treatment

[0106] Step S2 of the same insertion and cutting mode;

[0107] Step c: Molding and processing

[0108] The inner and outer diameters are formed by turning on a Mazak machine tool, so that the roundness tolerance can reach 0.005mm or 0.01mm;

[0109] Use CNC4 to pre-form the pocket. When the diameter is ≤500mm, leave 0.1-0.15mm on one side; when the diameter is >500mm, leave 0.15-0.2mm on one side.

[0110] The pocket finishing process is performed on a CNC5 machine using a carbide cutting tool at a turning speed of 150-200 m / min or 100-150 m / min and a feed rate of 0.08-0.12 mm / r or 0.06-0.09 mm / r. Before finishing the pocket, the accuracy of the pocket reference surface must be ensured by turning. For diameters > 500 mm, an additional turning process for the pocket positioning surface is added, with a flatness tolerance of ≤ 0.01 mm and radial runout of ≤ 0.005 mm. At the same time, the pocket turning adopts a circular interpolation turning strategy: single-edge turning is used for diameters ≤ 500 mm, and multi-edge segmented turning is used for diameters > 500 mm, with each segment having an arc length of ≤ 100 mm. After turning, the R-value deviation of the pocket is ≤ 0.003 mm.

[0111] Step d: Detection and calibration

[0112] The allowable tolerance for the contour accuracy of the first piece measured by three-dimensional coordinate measuring machine is 0.003mm or 0.005mm, and the allowable tolerance for the R value of the pocket is 0.002mm or 0.003mm. The first piece of each batch of 2 pieces is calibrated. When processing 40 pieces or 20-30 pieces in batch, check the tool. When processing 150 pieces or 100-120 pieces or when the quality is abnormal, replace the tool.

[0113] Step e: Post-processing

[0114] Step S5 of the same insertion and cutting mode;

[0115] (3.2) High-efficiency precision turning method

[0116] Step A: Material preparation and incoming material inspection

[0117] Based on step S1, eddy current testing is added to check for internal defects in blanks with a diameter > 800 mm to ensure that there are no defects such as cracks or inclusions that affect processing performance.

[0118] Step B: Material Aging Treatment

[0119] Based on step S2, for high-strength alloy materials, a medium-temperature tempering treatment of 200℃×4 hours is added to further stabilize the metallographic structure of the material and improve the uniformity of the material hardness.

[0120] Step C: Molding Processing

[0121] The inner and outer diameters are turned simultaneously using a dual-spindle linkage lathe, achieving a roundness tolerance of 0.004mm, which is 20% more accurate than the traditional method.

[0122] Specialized CNC lathes are used for pre-forming of the pockets. For diameters ≤500mm, a single-sided allowance of 0.08-0.12mm is provided, and for diameters >500mm, a single-sided allowance of 0.12-0.18mm is provided, resulting in more precise allowances.

[0123] High-precision CNC lathe for pocket turning, using ultra-fine grain carbide cutting tools, turning speed 220-280m / min, feed rate 0.05-0.1mm / r, with cutting fluid constant temperature control system, temperature is controlled at 20±2℃, reducing the impact of thermal deformation on machining accuracy;

[0124] In addition, the precision turning of the pocket adopts an adaptive feed adjustment system, which automatically adjusts the feed rate within the range of 50-150N based on the real-time detected changes in cutting force. When the cutting force exceeds 150N, the feed rate is automatically reduced by 10%-15%, and when the cutting force is below 50N, the feed rate is automatically increased by 5%-10% to ensure a balance between machining efficiency and surface quality. For bearing retainers with a diameter >1000mm, a split turning fixture is used to divide the workpiece into 3-4 fan-shaped areas for step-by-step turning. After each area is turned, the splicing accuracy is checked, and the allowable gap tolerance at the splicing point is ≤0.003mm to ensure the machining accuracy of large workpieces.

[0125] Step D: Detection and Calibration

[0126] In addition to the inspection content in step d, a laser interferometer is added to check the position of the pocket, with a tolerance of ≤0.002mm; 5 sampling inspections are added to the first piece of each batch to cover pockets in different positions; the tool is checked when 30 or 15-25 pieces are processed in batches, and the tool is replaced when 120 or 80-100 pieces are processed or when the quality is abnormal. The tool replacement frequency is higher to ensure processing stability.

[0127] Step E: Post-processing

[0128] Based on step S5, a precision grinding process is added to grind the edge of the pocket with a precision of 0.005mm, further reducing the surface roughness to Ra≤0.8μm.

[0129] Example 1: Pocket milling mode (diameter 100mm)

[0130] Step S3: Rough milling of the pocket: TC4 tool, cutting speed 90m / min, feed rate 0.1mm / r, axial depth 2.5mm / pass, leave 0.2mm allowance;

[0131] Precision forming: W18Cr4V tool, cutting speed 120m / min, feed rate 0.06mm / r, delamination depth 0.08mm;

[0132] In batch processing, the tool is inspected for 50 pieces, and a forced tool change is performed for 200 pieces.

[0133] Example 2: Pocket milling mode (diameter 800mm)

[0134] Step S3: Rough milling of the hole: reinforced TC4 tool, cutting speed 75m / min, feed rate 0.09mm / r, axial depth 1.5mm / pass, with a 0.3mm allowance;

[0135] Precision forming: W18Cr4V coated tool, cutting speed 110m / min, feed rate 0.045mm / r, delamination depth 0.06mm;

[0136] In batch processing, 30 pieces require tool inspection, and 150 pieces require forced tool replacement.

[0137] Example 3: Hole-cutting method (diameter 300mm)

[0138] Step S3: Pre-forming the pocket: Leave a 0.12mm allowance;

[0139] Finishing: CCMT09T304 cutting tool, circular interpolation speed 180m / min, feed rate 0.1mm / r, single-edge turning;

[0140] During batch processing, 40 pieces require tool inspection, and 150 pieces require forced tool replacement.

[0141] Example 4: Hole-turning method (diameter 1000mm)

[0142] Step S3: Pocket preforming: Leave a 0.18mm allowance;

[0143] Finishing: CCMT12T304 cutting tool, segmented turning speed 120m / min, feed rate 0.08mm / r, arc length of each segment 80mm;

[0144] During batch processing, 25 pieces were inspected using cutting tools, and 110 pieces were forced to have their tools changed.

[0145] The bearing retainers processed in all four embodiments passed the precision test: the roundness of the corresponding diameter was ≤0.005mm (small diameter) / 0.01mm (large diameter), and the R-value deviation of the pocket was ≤0.002mm (small diameter) / 0.003mm (large diameter), meeting the requirements for high-precision bearing assembly.

[0146] The bearing retainer in this application is made of aluminum bronze. The aluminum content generally does not exceed 11.5%, and sometimes appropriate amounts of iron, nickel, manganese, and other elements are added to further improve performance. Aluminum bronze can be heat-treated for strengthening; its strength is higher than tin bronze, and it also has better resistance to high-temperature oxidation.

[0147] Aluminum bronze has high strength and good wear resistance, and is used for high-strength screws, nuts, copper sleeves, sealing rings, and wear-resistant parts. Its most prominent feature is its excellent wear resistance.

[0148] Aluminum bronze possesses many excellent properties. It has high strength, hardness, and wear resistance, making it commonly used to manufacture gear blanks, threaded parts, and other components. Aluminum bronze exhibits excellent corrosion resistance, making it suitable for manufacturing corrosion-resistant parts such as propellers and valves. Aluminum bronze does not generate sparks under impact, making it suitable for manufacturing spark-free tool materials. It has excellent thermal conductivity and stable stiffness, making it a promising mold material when used in the stretching and rolling of stainless steel plate heat exchangers, preventing sticking and workpiece scratches. Aluminum bronze also exhibits shape memory effect and has been developed as a shape memory alloy. Aluminum bronze alloys are relatively inexpensive, making them a partial substitute for some expensive metals, such as tin bronze, stainless steel, and nickel-based alloys. Due to its superior properties, aluminum bronze is increasingly favored and plays an important role in both civilian and military industries.

[0149] The influence of chemical composition on the microstructure and properties of aluminum bronze has always been a focus of attention. Firstly, there is no clear definition of whether chemical composition has a positive or negative effect on alloys. For example, iron added to aluminum bronze generally refines the grain, reduces spontaneous temper brittleness, and improves mechanical properties. However, when the iron content is high, iron will precipitate as Fe3Al2 compounds, worsening the mechanical properties of the alloy; therefore, the iron content should not exceed 5%. Zinc is another element; many studies suggest that it can improve the plasticity of the metal after solid solution with the base metal, while others consider it an impurity element. This shows that the role of alloying elements cannot be generalized. It is generally believed that adding appropriate amounts of alloying elements can improve the mechanical properties of the alloy; for example, adding appropriate amounts of iron forms aluminum-iron bronze, adding manganese forms aluminum-manganese bronze, and adding nickel forms aluminum-nickel bronze. Secondly, there is no clear definition of the requirements for the content of impurity elements. It is precisely because of the variation in chemical composition that aluminum bronzes have different types and applications.

[0150] Strengthening processes are typically employed to improve the microstructure of aluminum bronze alloys in order to achieve the desired performance and processing characteristics.

[0151] The following is the material testing report:

[0152] Test item: Chemical composition GB / T1176-1987;

[0153] Vickers hardness GB / T 4340.1-1999;

[0154] Temperature / humidity tested: 23.2℃ / 10%RH;

[0155] Test results:

[0156] Table 1 Hardness Test

[0157]

[0158] Table 2 Chemical Composition Unit:wt%

[0159]

[0160] Note: The chemical composition of the materials is based on GB / T1176-1987 standard;

[0161] Testing items and specifications: tensile strength / yield strength / elongation;

[0162] Testing instrument and serial number: Universal testing machine;

[0163] Temperature / humidity test: (20+5)℃, (40~70)%RH;

[0164] Sample Description: Aluminum Bronze (ZCuA1) 10Tensile testing of Fe3Mn2 material was conducted on 2 pieces.

[0165] Table 3 Tensile / Yield Strength / Elongation

[0166] Sample identification Yield strength (Rpo.2) / MPa Tensile strength (Rm) / MPa <![CDATA[Elongation (A 50 ) / %]]> Reduction of area / % 1 297 699 34.8 44 2 295 697 34.9 44

[0167] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A bearing retainer processing technology, characterized in that: This includes bearing retainer machining processes using the cutting method, milling method, and turning method. (1) The machining process of the bearing retainer in the broaching mode is as follows: Step S1: Material preparation and incoming material inspection Centrifugal tubing is used for material preparation using Dahe machine tools to obtain blanks of corresponding specifications for bearing retainers with diameters ranging from 1 to 1200 mm. A three-piece integrated clamping method is adopted, with a clamping distance of 20 mm for diameters ≤ 500 mm and 30-50 mm for diameters > 500 mm. The total length and inner and outer diameter allowances are measured using vernier calipers, and the material composition is inspected using a metallographic analyzer and compared with the factory composition to ensure material qualification. Step S2: Material aging treatment The aging treatment of the material was completed within 48 hours, specifically a high-temperature treatment of 120℃ for 8 hours and a low-temperature treatment of -20℃ for 16 hours, in order to stabilize the material properties. Step S3: Molding Process First, the inner and outer diameters are shaped using a Mazak machine tool to achieve a roundness tolerance of 0.005mm or 0.01mm. Subsequently, a quick 4-axis machining center was used for roughing the pocket using a planing method, with TC4 carbide tools selected. The cutting speed was 90 m / min or 70-80 m / min, and the feed rate was 0.12 mm / r or 0.08-0.1 mm / r. The axial feed depth of the tool was 2-3 mm / stroke for diameters ≤ 500 mm and 1-2 mm / stroke for diameters > 500 mm. A finishing allowance was reserved for the pocket: 0.2 mm for diameters ≤ 500 mm and 0.3 mm for diameters > 500 mm. Finally, the hole was precision shaped by inserting and shaping using a Yasuda 5-axis machining center. W18Cr4V high-speed steel tools were used, with a cutting speed of 130 m / min or 100-120 m / min and a feed rate of 0.06 mm / r or 0.04-0.05 mm / r. A layered inserting strategy was employed: for diameters ≤ 500 mm, the depth of cut per layer was 0.05-0.1 mm; for diameters > 500 mm, the depth of cut per layer was 0.03-0.08 mm, resulting in a surface roughness of Ra ≤ 1.6 μm or Ra ≤ 3.2 μm for the hole. Step S4: Detection and Calibration The contour accuracy and pocket R-value of the first piece are measured using a three-dimensional measuring machine. The allowable tolerance for contour accuracy is 0.003mm or 0.005mm, and the allowable tolerance for pocket R-value is 0.002mm or 0.003mm. Two first pieces are calibrated for each batch. The cutting tools are checked when processing 50 or 30 pieces in batch, and the cutting tools are replaced when processing 200 or 150 pieces or when quality abnormalities occur. Step S5: Post-processing Remove burrs with a copper wire brush, clean with ultrasonic cleaner, apply oil, then pack with kraft paper gloves and place in layers. (2) The milling process for bearing retainers is as follows: Step M1: Material preparation and incoming material inspection The same step S1 as the cutting mode ensures that the billet specifications and quality meet the requirements; Step M2: Material Aging Treatment In step S2 of the same planing mode, the material properties are stabilized through high and low temperature treatment; Step M3: Molding Process The inner and outer diameters of the bearing retainer are milled using a high-precision milling machine to ensure that the roundness tolerance is ≤0.006mm; For rough machining of the pocket, use a special milling cutter for rough milling. Select appropriate parameters according to the diameter of the bearing retainer: when the diameter is ≤500mm, the milling speed is 80-100m / min and the feed rate is 0.1-0.15mm / r; when the diameter is >500mm, the milling speed is 60-80m / min and the feed rate is 0.08-0.12mm / r. The finishing of the pocket is carried out using a CNC milling machine with a high-performance carbide end mill. When the diameter is ≤500mm, the milling speed is 120-140m / min and the feed rate is 0.05-0.08mm / r; when the diameter is >500mm, the milling speed is 100-120m / min and the feed rate is 0.04-0.06mm / r, to ensure the accuracy and surface quality of the pocket. Step M4: Detection and Calibration The contour accuracy, pocket size, and positional accuracy of the first piece are inspected using a three-dimensional measuring instrument. The allowable tolerance for contour accuracy is 0.004mm, the allowable tolerance for pocket size is ±0.003mm, and the allowable tolerance for positional accuracy is ≤0.005mm. The first piece calibration quantity for each batch is 2 pieces. The cutting tool is inspected when 40 pieces are processed in a batch, and the cutting tool is replaced when 180 pieces are processed or when quality problems occur. Step M5: Post-processing First, deburr the material, then clean it with a special cleaning agent, then apply rust prevention treatment, and finally package it in a special packaging box. (3) The machining process for bearing retainers in turning mode is as follows: (3.1) Conventional turning method Step a: Material preparation and incoming material inspection Same as step S1 in the insertion and cutting mode; Step b: Material aging treatment Same as step S2 in the insertion and cutting mode; Step c: Molding and processing The inner and outer diameters are formed by turning on a Mazak machine tool, so that the roundness tolerance can reach 0.005mm or 0.01mm; Use CNC4 to pre-form the pocket. When the diameter is ≤500mm, leave 0.1-0.15mm on one side; when the diameter is >500mm, leave 0.15-0.2mm on one side. The pocket finishing process is performed on a CNC5 machine using a carbide cutting tool at a turning speed of 150-200 m / min or 100-150 m / min and a feed rate of 0.08-0.12 mm / r or 0.06-0.09 mm / r. Before finishing the pocket, the accuracy of the pocket reference surface must be ensured by turning. For diameters > 500 mm, an additional turning process for the pocket positioning surface is added, with a flatness tolerance of ≤ 0.01 mm and radial runout of ≤ 0.005 mm. At the same time, the pocket turning adopts a circular interpolation turning strategy: single-edge turning is used for diameters ≤ 500 mm, and multi-edge segmented turning is used for diameters > 500 mm, with each segment having an arc length of ≤ 100 mm. After turning, the R-value deviation of the pocket is ≤ 0.003 mm. Step d: Detection and calibration The allowable tolerance for the contour accuracy of the first piece measured by three-dimensional coordinate measuring machine is 0.003mm or 0.005mm, and the allowable tolerance for the R value of the pocket is 0.002mm or 0.003mm. The first piece of each batch of 2 pieces is calibrated. When processing 40 pieces or 20-30 pieces in batch, check the tool. When processing 150 pieces or 100-120 pieces or when the quality is abnormal, replace the tool. Step e: Post-processing Step S5 is the same as the insertion and cutting mode; (3.2) High-efficiency precision turning method Step A: Material preparation and incoming material inspection Based on step S1, eddy current testing is added to check for internal defects in blanks with a diameter > 800 mm to ensure that there are no defects such as cracks or inclusions that affect processing performance. Step B: Material Aging Treatment Based on step S2, for high-strength alloy materials, a medium-temperature tempering treatment of 200℃×4 hours is added to further stabilize the metallographic structure of the material and improve the uniformity of the material hardness. Step C: Molding Processing The inner and outer diameters are turned simultaneously using a dual-spindle linkage lathe, achieving a roundness tolerance of 0.004mm, which is 20% more accurate than the traditional method. Specialized CNC lathes are used for pre-forming of the pockets. For diameters ≤500mm, a single-sided allowance of 0.08-0.12mm is provided, and for diameters >500mm, a single-sided allowance of 0.12-0.18mm is provided, resulting in more precise allowances. High-precision CNC lathe for pocket turning, using ultra-fine grain carbide cutting tools, turning speed 220-280m / min, feed rate 0.05-0.1mm / r, with cutting fluid constant temperature control system, temperature is controlled at 20±2℃, reducing the impact of thermal deformation on machining accuracy; In addition, the precision turning of the pocket adopts an adaptive feed adjustment system, which automatically adjusts the feed rate within the range of 50-150N based on the real-time detected changes in cutting force. When the cutting force exceeds 150N, the feed rate is automatically reduced by 10%-15%, and when the cutting force is below 50N, the feed rate is automatically increased by 5%-10% to ensure a balance between machining efficiency and surface quality. For bearing retainers with a diameter >1000mm, a split turning fixture is used to divide the workpiece into 3-4 fan-shaped areas for step-by-step turning. After each area is turned, the splicing accuracy is checked, and the allowable gap tolerance at the splicing point is ≤0.003mm to ensure the machining accuracy of large workpieces. Step D: Detection and Calibration In addition to the inspection content in step d, a laser interferometer is added to check the position of the pocket, with a tolerance of ≤0.002mm; 5 sampling inspections are added to the first piece of each batch to cover pockets in different positions; the tool is checked when 30 or 15-25 pieces are processed in batches, and the tool is replaced when 120 or 80-100 pieces are processed or when the quality is abnormal. The tool replacement frequency is higher to ensure processing stability. Step E: Post-processing Based on step S5, a precision grinding process is added to grind the edge of the pocket with a precision of 0.005mm, further reducing the surface roughness to Ra≤0.8μm.

2. The bearing retainer processing technology according to claim 1, characterized in that: In step S3, when roughing the pocket by insert milling, the axial feed depth of the tool is 2-3 mm / time for diameters ≤ 500 mm and 1-2 mm / time for diameters > 500 mm; leave a finishing allowance of 0.2 mm for pockets with diameters ≤ 500 mm or 0.3 mm for pockets with diameters > 500 mm.

3. The bearing retainer processing technology according to claim 1, characterized in that: In step S3, a layered milling strategy is adopted when milling the pocket: for diameters ≤ 500mm, the cutting depth of each layer is 0.05-0.1mm; for diameters > 500mm, the cutting depth of each layer is 0.03-0.08mm; and the surface roughness of the pocket Ra is ≤ 1.6μm or Ra ≤ 3.2μm.

4. The bearing retainer processing technology according to claim 1, characterized in that: Before precision machining of the pocket in step c, the accuracy of the pocket reference surface must be ensured by turning. When the diameter is > 500 mm, a turning process for the pocket positioning surface is added. The flatness tolerance is ≤ 0.01 mm and the radial runout is ≤ 0.005 mm.

5. The bearing retainer processing technology according to claim 1, characterized in that: In step c, the pocket turning adopts the circular interpolation turning strategy: for diameters ≤500mm, single-edge turning is used; for diameters >500mm, multi-edge segmented turning is used, with each segment having an arc length ≤100mm. After turning, the deviation of the pocket R value is ≤0.003mm.

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