A super-light series bearing ring forging machining process and a forging structure

Abstract

The application discloses a kind of ultra-light series bearing ring forging machining process and forging structure, belongs to bearing ring forging machining technical field, specifically includes the following operation: S1, forging forming;S2, one sequence unilateral profile integration turning;S3, two sequences without shielding full profile finishing;S4, heat treatment;S5, inner and outer diameter precision grinding;S6, finished product detection.The application adopts the above-mentioned ultra-light series bearing ring forging machining process and forging structure, the deformation resistance of blank is greatly improved;The coaxiality error is compensated by the centering clamp, and the stress is clamped uniformly by the full-pack spring clamp, so that elastic deformation is avoided during clamping;The machining precision is significantly improved;The machining process is simplified, and the production efficiency is improved;Most of the ultra-light series bearing rings can be batch adapted, without modifying existing lathe equipment, just replacing the clamp and tool can be landed, with low modification cost and strong landing performance.

Description

Technical Field

[0001] This invention relates to the field of bearing ring forging and machining technology, and in particular to a forging and machining process and forging structure for ultra-light series bearing rings. Background Technology

[0002] With the rapid development of new energy equipment, aviation drones, and lightweight transmission equipment, the market demand for ultra-light thin-walled bearings continues to rise. These bearings require extremely low weight and ultra-thin walls, with an outer diameter to inner diameter ratio (D / d) ≤ 1.25 and a wall thickness to outer diameter ratio (t / D) < 0.10. The actual wall thickness of the finished bearing ring is no more than 2mm, resulting in extremely poor structural rigidity and significantly higher processing difficulty than conventional standard bearings. The current mainstream processing technology for ultra-light bearings suffers from the following core challenges: like Figure 1 As shown, traditional ultralight bearings use hollow ring-shaped forgings with uniform wall thickness. The blanks lack overall reinforcement and rarely undergo sizing processes. After forging, the blanks are prone to elliptical deformation, which easily leads to elastic deformation under stress during subsequent machining, clamping, and cutting. This directly results in out-of-tolerance dimensions and roundness issues for the bearing's inner and outer diameters. Although the first machining stage uses a self-aligning fixture to hold the thin-walled bearing's outer wall, the extremely poor rigidity of the forgings means that the self-aligning fixture cannot completely solve the problem. The clamping force is difficult to control precisely. Excessive clamping force directly deforms the bearing, causing localized depressions, and the ellipticity and roundness are difficult to guarantee after the fixture is released. Insufficient clamping force causes the workpiece to move during cutting, resulting in unstable machining dimensions. The second-stage spring fixture, due to the poor foundation of the semi-finished product in the first stage, can only ensure that the ellipticity and roundness tolerances of its own machined parts are not amplified after adjustment. The inner and outer diameters, the radius arc surface, and the end face are machined in multiple stages, resulting in obvious tool marks from multiple tool changes and process changes. The surface roughness of the bearing cannot meet the high-precision assembly requirements of lightweight equipment, and the subsequent grinding workload is large. Poor tool compatibility: When conventional large-tip radius tools cut thin-walled workpieces, the cutting resistance is high, which easily produces vibration waves, further damaging the bearing surface accuracy and resulting in low machining efficiency.

[0003] Therefore, the existing ultralight bearing processing technology is not suitable for the processing requirements of thin-walled lightweight structures. There are a series of problems such as easy deformation of blanks, serious deformation during clamping, poor accuracy, and high scrap rate. It is urgent to optimize the matching process of forging structure with turning tooling and cutting tools to solve the common processing problems in the industry. Summary of the Invention

[0004] The purpose of this invention is to provide a forging and machining process and forging structure for ultra-light series bearing rings, which significantly improves the deformation resistance of the billet: the concave reinforced forging structure increases the rigidity of the billet, and the forging billet is calibrated to reduce deformation defects from the source; elastic deformation caused by clamping is avoided: the self-aligning fixture compensates for coaxiality errors and the fully enclosed spring fixture provides uniform stress clamping, reducing the deformation of the bearing during machining and fully meeting the precision requirements of thin-walled bearings; machining accuracy is significantly improved: the two-stage integrated forming eliminates tool marks caused by multiple tool changes and process changes, reduces the surface roughness and ellipticity / roundness errors of the inner and outer R-arc surfaces of the bearing, and improves the product qualification rate; the machining process is simplified, and production efficiency is improved: the turning process is reduced from three to two, shortening the machining time of a single bearing and increasing production capacity; it has wide adaptability: it can be batch adapted to the machining of most ultra-light series bearing rings, without the need to modify existing lathe equipment, only the fixtures and tools need to be changed, the modification cost is low, and the implementation is highly feasible.

[0005] To achieve the above objectives, the present invention provides a forging and machining process for ultra-light series bearing rings, specifically including the following operations: S1, Forging and shaping; S2, One-way single-sided integrated turning; S3, two-stage unobstructed full-surface finishing; S4, heat treatment; S5, Precision grinding of inner and outer diameters; S6. Finished product inspection.

[0006] Preferably, in S1, an approximately U-shaped annular forged bearing blank is prepared, retaining the complete inner hole, and a wall thickness reinforcement section is provided on one side.

[0007] Preferably, in S2, a self-aligning fixture is selected as the tooling, and the clamping position is selected on the outer circle of the side with the larger wall thickness of the forged bearing blank. The clamping length is not greater than the sum of the single-sided allowance of the end face and the radial coordinate length of the outer R arc surface.

[0008] Preferably, in S2, a special precision turning tool with a small tip radius and high cutting edge sharpness is selected, with a tip radius ≤0.4mm.

[0009] Preferably, in S2, all surface machining of the forging, excluding the clamping area, including the outer diameter, inner diameter, single-sided end face, inner R arc surface, and outer R arc surface, is completed in one clamping operation without secondary correction. This ensures that the maximum wall thickness of the forging remains intact and guarantees the rigidity of the forging.

[0010] Preferably, in step S3, the workpiece processed in step S2 is flipped over, and a fully enclosed spring clamp is used for clamping, directly completing the finishing of all remaining areas of the other end face, inner R arc surface, and outer R arc surface of the workpiece.

[0011] Preferably, the S3 full-wrap spring clamp adopts an elastic wrap-around full-wrap structure, which evenly wraps the machined outer side wall of the workpiece, and has no radial or end face obstruction.

[0012] This invention provides a forging structure for machining ultra-light series bearing rings using a forging machine. It is applied to the aforementioned ultra-light series bearing ring forging machine processing technology. The forged bearing blank has a local wall thickness reinforcement structure reserved on one side to form a concave cross section. The ratio of the outer diameter to the inner diameter of the wall thickness reinforcement structure is greater than 1.25, and the ratio of the wall thickness to the outer diameter is greater than 0.1.

[0013] Therefore, the present invention, employing the above-mentioned forging and machining process and forging structure of an ultra-light series bearing ring, has the following beneficial effects: 1) Significantly improved resistance to deformation of billets: The concave-shaped reinforced forging structure improves the rigidity of billets, and the forging billets are sized to reduce deformation defects from the source. 2) Avoid elastic deformation during clamping: The self-aligning fixture compensates for coaxiality error and the fully enclosed spring fixture provides uniform stress clamping, reducing the deformation during bearing machining and fully meeting the precision requirements of thin-walled bearings. 3) Significantly improved machining accuracy: The two processes are integrated into one molding process, eliminating tool marks caused by multiple tool changes and process changes, reducing the surface roughness and ellipticity / roundness errors of the inner and outer R-arc surfaces of the bearing, and improving the product qualification rate; 4) Streamlined machining process and improved production efficiency: The turning process has been reduced from three steps to two, shortening the machining time for a single bearing and increasing production capacity; 5) Wide adaptability: It can be batch adapted to the processing of most ultra-light series bearing rings without modifying existing lathe equipment. Only the fixtures and tools need to be changed to implement the project. The modification cost is low and the project can be implemented with strong adaptability.

[0014] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0015] Figure 1 This is a structural diagram of a forging made using traditional techniques; Figure 2 This invention relates to a forging and machining process for ultra-light series bearing rings, specifically a single-sided profile integrated turning process, including clamping and machining area diagrams. Figure 3 This invention relates to a forging and machining process for ultra-light series bearing rings, specifically a two-stage unobstructed full-surface finishing process, including clamping and machining locations. Figure 4 This is a schematic diagram of the forging structure of an ultra-light series bearing ring forging machine according to the present invention. Detailed Implementation

[0016] The technical solution of the present invention will be further described below with reference to the accompanying drawings and embodiments.

[0017] Unless otherwise defined, the technical or scientific terms used in this invention shall have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains. The terms "first," "second," and similar terms used in this invention do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0018] Example 1 This invention provides a forging and machining process for ultra-light series bearing rings, specifically including the following operations: S1, Forging and shaping; Prepare a bearing blank with an approximately U-shaped annular forging, retaining the complete inner hole, and setting a wall thickness reinforcement section on one side.

[0019] S2, One-way single-sided integrated turning; like Figure 2 As shown, a self-aligning fixture is selected as the tooling. The clamping position is selected on the outer circle of the side with the larger wall thickness of the forged bearing blank. The clamping length is not greater than the sum of the single-sided allowance of the end face and the radial coordinate length of the outer R arc surface, so as to ensure that the clamping area completely covers the area of ​​the workpiece with the greatest force and improve the clamping stability.

[0020] Special precision turning tools with small tip radius and high cutting edge sharpness are selected, with a tip radius ≤0.4mm, to reduce the cutting contact area and reduce the cutting resistance of thin-walled workpieces.

[0021] In a single clamping operation, all surface machining processes, excluding the clamping area, are completed in one go, including the outer diameter, inner diameter, single-sided end face, inner radius arc surface, and outer radius arc surface. No secondary correction is required, and the maximum wall thickness of the forging is always preserved without damage, ensuring the rigidity of the forging.

[0022] S3, two-stage unobstructed full-surface finishing; Flip the workpiece processed in S2, such as... Figure 3 As shown, by replacing the full-enclosed spring clamp, the remaining areas of the other end face, inner R arc surface and outer R arc surface of the workpiece can be finished directly. The clamping stress is evenly distributed throughout the entire area, with no localized stress concentration, thus completely avoiding the deformation of thin-walled workpieces by clamping.

[0023] The fully enclosed spring clamp adopts an elastic, fully enclosed structure that evenly wraps around the machined outer wall of the workpiece without radial or end-face obstruction.

[0024] S4, heat treatment; After machining, conventional vacuum heat treatment is performed to ensure that the bearing hardness meets the standard.

[0025] S5, Precision grinding of inner and outer diameters; S6. Finished product inspection; Conduct comprehensive testing on dimensional accuracy, roundness, surface roughness, and geometric tolerances before warehousing finished products.

[0026] like Figure 4 As shown, this invention provides a forging structure for machining ultra-light series bearing rings using a forging machine. Applied to the aforementioned ultra-light series bearing ring forging machine machining process, the forged bearing blank has a local wall thickness reinforcement structure reserved on one side to form a concave cross section. At the same time, strict dimensional control is implemented: the axial height of the wall thickness reinforcement area is as small as possible less than the machining allowance on one side of the bearing end face, the ratio of the outer diameter to the inner diameter of the wall thickness reinforcement structure is greater than 1.25, and the ratio of the wall thickness to the outer diameter is greater than 0.1. The forging process simultaneously adds a forging outer diameter shaping step.

[0027] Example 2 Model number: 71919CV.01 Ultra-light custom bearing ring, outer diameter of the ring is 130mm, wall thickness is 6mm at the maximum and 4mm at the minimum, and the machining allowance on one side of the end face is 2.0mm.

[0028] Forging and shaping; Prepare an approximately U-shaped ring forging, basically retaining the complete inner hole, and setting a wall thickness reinforcement section on one side. Control the axial height (H) of the reinforcement section to be 1.9mm, which is less than the 2.0mm allowance on one side of the end face, to ensure that the thickened structure can be completely removed by turning; add a diameter adjustment process to the forging, and the overall blank ovality is ≤0.3mm.

[0029] One-step single-sided profile integrated turning; Equipment: Slant rail horizontal CNC lathe; Tooling: Floating self-aligning fixture; Clamping method: Clamp the outer circle of the thick-walled side of the bearing, with a clamping length of 5mm, which is less than 2.0mm (end face allowance) + 3.5mm (radial coordinate length of the outer R arc surface) = 5.5mm; Cutting tool: 0.4mm tip radius, P-type bearing steel CNC machine tool insert; Machining details (emphasis added): A single pass completes the integrated turning of the non-clamping side end face, the outer diameter radius (R) arc surface, and the inner cavity radius (R) surface. Roughing depth of cut is 0.6mm, feed rate is 0.2mm / rpm, and spindle speed is 300 rpm. Finishing depth of cut is 0.3mm, feed rate is 0.1-0.15mm / rpm, and spindle speed is 350 rpm. No intermediate clamping is required. The ovality and roundness of the machined products are generally within 0.03mm, and the defect rate is below 0.5%.

[0030] Second-order unobstructed full-surface finishing; Equipment: Slant rail horizontal CNC lathe; Tooling: Fully enclosed elastic spring clamp; Clamping method: The workpiece is clamped around the pre-machined outer wall, and the pressure is adjusted to 0.5MPa, with uniform pressure applied throughout the entire area; Cutting tool: 0.4mm tip radius, P-type bearing steel CNC machine tool insert; Machining content (heavy area): Complete the finishing of the other end face of the workpiece and the remaining inner and outer radius arc surfaces in one go. The machining parameters are set for the entire process: depth of cut 0.3mm, feed rate 0.1-0.15mm / rpm, spindle speed 350rpm, and no machining blind spots.

[0031] The bearing undergoes quenching and tempering heat treatment to ensure a hardness of HRC60~62; the surface and inner and outer diameters are ground; dimensional accuracy, roundness, surface roughness, and geometric tolerances are fully inspected; and the qualified bearings are then put into the assembly warehouse.

[0032] Comparative Example 1 We manufacture the same 71919CV.01 ultralight bearing rings.

[0033] Traditional craftsmanship: It adopts ring forgings with equal wall thickness, three turning processes, and conventional standard tool tip radius of 1.2-0.8.

[0034] Test results: maximum ovality of blank is 0.8mm, machining and clamping deformation is 0.05mm, maximum ovality is 0.10mm, maximum edge roundness is 0.12mm, and the defect rate is 20%.

[0035] The processing technology provided by this invention: Two turning operations are completed, and the radius of the CNC machine tool with a clipped insert is 0.4 for turning P-type bearing steel.

[0036] Test results: The maximum ellipticity of the blank was 0.3mm, the deformation during machining and clamping was 0.01mm, the ellipticity was 0.03mm, the edge roundness was 0.04mm, the defect rate was 0.5%, and the processing efficiency was improved by 10%.

[0037] Therefore, this invention adopts the above-mentioned ultra-light series bearing ring forging machining process and forging structure, which greatly improves the blank's resistance to deformation: the concave-shaped reinforced forging structure increases the rigidity of the blank, and the forging blank is calibrated to reduce blank deformation defects from the source; elastic deformation caused by clamping is avoided: the self-aligning fixture compensates for coaxiality errors and the fully enclosed spring fixture provides uniform stress clamping, reducing the amount of bearing machining clamping deformation and fully meeting the precision requirements of thin-walled bearings; machining accuracy is significantly improved: the two processes are integrated into one forming process, eliminating tool marks caused by multiple tool changes and process changes, reducing the surface roughness and ellipticity / roundness errors of the inner and outer R-surfaces of the bearing, and improving the product qualification rate; the machining process is simplified, and production efficiency is improved: the turning process is reduced from three to two, shortening the machining time of a single bearing and increasing production capacity; it has wide adaptability: it can be batch adapted to the machining of most ultra-light series bearing rings, without the need to modify existing lathe equipment, only the fixtures and tools need to be changed, the modification cost is low, and the implementation is strong.

[0038] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. 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 still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A forging and machining process for ultra-light series bearing rings, characterized in that: Specifically, the following operations are included: S1, Forging and shaping; S2, One-way single-sided integrated turning; S3, two-stage unobstructed full-surface finishing; S4, heat treatment; S5, Precision grinding of inner and outer diameters; S6. Finished product inspection.

2. The forging and machining process for ultra-light series bearing rings according to claim 1, characterized in that: In S1, an approximately U-shaped annular forged bearing blank is prepared, retaining the complete inner hole, and a wall thickness reinforcement section is set on one side.

3. The forging and machining process for ultra-light series bearing rings according to claim 2, characterized in that: In S2, a self-aligning fixture is selected as the tooling. The clamping position is selected on the outer circle of the forged bearing blank with the larger wall thickness. The clamping length is not greater than the sum of the single-sided allowance of the end face and the radial coordinate length of the outer R arc surface.

4. The forging and machining process for ultra-light series bearing rings according to claim 3, characterized in that: S2 uses a special precision turning tool with a small tip radius and high cutting edge sharpness, with a tip radius ≤0.4mm.

5. The forging and machining process for ultra-light series bearing rings according to claim 4, characterized in that: In S2, all surface machining of the forging, excluding the clamping area, including the outer diameter, inner diameter, single-sided end face, inner R arc surface, and outer R arc surface, is completed in one clamping operation without secondary correction. This ensures that the maximum wall thickness of the forging remains intact and guarantees the rigidity of the forging.

6. The forging and machining process for ultra-light series bearing rings according to claim 5, characterized in that: In S3, the workpiece processed in S2 is flipped over, and a fully enclosed spring clamp is used for clamping, directly completing the finishing of all remaining areas of the other end face, inner R arc surface, and outer R arc surface of the workpiece.

7. The forging and machining process for ultra-light series bearing rings according to claim 6, characterized in that: The S3 full-wrap spring clamp adopts an elastic wrap-around full-wrap structure, which evenly wraps around the machined outer wall of the workpiece, without radial or end face obstruction.

8. A forging structure for machining ultra-light series bearing rings by forging and turning, applied to the forging and turning process for ultra-light series bearing rings as described in any one of claims 1-7, characterized in that: The forged bearing blank has a local wall thickness reinforcement structure reserved on one side to form a concave cross section. The ratio of the outer diameter to the inner diameter of the wall thickness reinforcement structure is greater than 1.25, and the ratio of the wall thickness to the outer diameter is greater than 0.1.

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