A cold-state spin-riveting forming process for driving shaft housing end face spline

Abstract

This invention relates to the field of spline technology for drive shaft housings, and discloses a cold riveting forming process for end face splines of drive shaft housings. The process first involves a thorough cleaning of the workpiece end face and riveting area; then, the workpiece is placed on a special fixture for precise radial and circumferential positioning; subsequently, the riveting head's spindle angle is adjusted for tool calibration; during the riveting operation, the spindle drives the riveting head to rotate and revolve, coordinating with the revolution to compact the metal, allowing it to plastically flow and fill the tooth grooves. The spindle's axial feed is precisely controlled in three stages: rapid approach, working feed forming, and pressure holding and shaping. This three-stage feed mode effectively balances processing efficiency and forming quality, reduces metal elastic rebound, and improves spline dimensional accuracy and structural stability. Compared to traditional processes, this solution eliminates the need for large forging equipment, simplifies the process, reduces energy consumption, and increases material utilization. It also ensures continuous metal fiber structure, resulting in excellent mechanical properties of the finished product and enabling high-precision spline forming in a single step.

Description

Technical Field

[0001] This invention relates to the field of spline machining technology for drive shaft housings, specifically a cold riveting forming process for the spline on the end face of a drive shaft housing. Background Technology

[0002] The spline on the end face of the drive shaft housing is mainly used for torque transmission. At present, the mainstream processing technology in the industry includes three categories: forging machining, pure cutting machining, and conventional cold riveting. Each of these processes has obvious shortcomings.

[0003] In the forging machining process, spline blanks need to be prepared by die forging using large-tonnage equipment, and then the tooth profile is finished by precision forging and machining. It requires large forging equipment of 2,500 tons or more, resulting in high equipment investment and energy consumption; the tooth profile accuracy of the forgings is only IT10~IT11 grade, requiring a secondary finishing process; the life of the forging die is only 8,000~10,000 pieces, resulting in high die usage costs.

[0004] In pure cutting processes, milling, gear hobbing, planing, grinding, and other methods are used to directly shape the material, resulting in a large amount of material removal and a material utilization rate of less than 60%. Cutting processes cut off the continuous fibrous structure of metal, causing the fatigue strength of spline tooth surfaces to decrease by 15% to 20%. At the same time, tool wear is rapid, and the overall cost is high for mass production.

[0005] Cold riveting has been gradually applied due to its advantages of high efficiency and low energy consumption. There are also relevant solutions for using cold riveting in spline machining. However, existing cold riveting generally adopts a single uniform speed feed mode. The single feed mode is difficult to balance production efficiency and forming quality: high speed throughout the process can easily cause uneven workpiece extrusion deformation, cracks, material shortages and other defects; low speed throughout the process will greatly extend the processing time, making it difficult to improve production efficiency, and cannot effectively offset the elastic recovery of metal, resulting in poor dimensional stability of the finished product.

[0006] Furthermore, existing cold riveting processes are mostly only applicable to low-precision splines at the hub bearing opening, and have not been specifically optimized for the high-precision, high-load-bearing requirements of drive shaft housings. Therefore, a cold riveting forming process for the end face splines of drive shaft housings is proposed. Summary of the Invention

[0007] This invention provides a cold riveting forming process for the spline on the end face of a drive shaft housing. It adopts a three-stage graded feed, which balances processing efficiency and forming quality, suppresses metal springback, and meets the requirements of high-precision processing, thus solving the problems mentioned in the background art.

[0008] This invention provides the following technical solution: a cold riveting forming process for the spline on the end face of a drive shaft housing, comprising the following steps: S1, workpiece surface treatment: cleaning the end face of the workpiece to be riveted, as well as the riveting pressure and pre-forming area of ​​the end face spline; after treatment, checking the surface cleanliness of the riveting area to ensure that there are no oil films, rust pits, or sharp burrs, thus ensuring that the riveting head and the end face of a single workpiece have uniform and controllable riveting deformation during the riveting process; S2, loading and positioning process: smoothly transferring the workpiece to be riveted and placing it in a special positioning fixture; relying on the positioning fixture to complete the radial limitation of the workpiece. The clamping and circumferential angle locking achieves bidirectional high-precision positioning of the workpiece, limiting the coaxiality and circumferential rotation deviation of the workpiece to within the allowable range of the process. After the limit locking, the radial runout of the workpiece is ≤0.02mm and the circumferential runout is ≤0.01mm, thereby avoiding workpiece offset and rotation during riveting and providing a reliable clamping reference for subsequent riveting operations; S3, Riveting head tool setting calibration: The lifting mechanism carries the riveting head vertically downward until the end of the riveting head is close to the end face of the workpiece to be riveted; and the riveting angle is set according to the number of spline teeth and the tooth groove depth after the workpiece is formed; S4, Riveting forming: The main spindle of the equipment starts. The riveting head rotates and slowly descends axially to apply extrusion force to the workpiece. Simultaneously, the riveting head and workpiece undergo relative revolution and rolling action. Under continuous extrusion, the metal at the workpiece end undergoes plastic flow, uniformly filling the tooth groove and completing the riveting integral forming. S5, Comprehensive Quality Inspection: Only after all inspection items pass can the next process be initiated. Unqualified workpieces are individually marked and isolated. In step S4, riveting forming, the feed process of the riveting head spindle adopts a three-stage graded control, which includes the following steps: S401, Rapid Approach Stage... S401, Section 1: Axial feed speed is set to 50-100 mm / s. The riveting head moves quickly to a position 1-2 mm away from the workpiece end face and then stops high-speed feed; S402, Section 2: Working feed stage: Switch to low-speed feed mode, feed speed is controlled at 0.5-2.0 mm / s, total axial feed displacement is the sum of spline design depth h and compression allowance δ, where compression allowance δ is 0.1-0.3 mm; S403, Section 3: Holding pressure and shaping stage: Axial feed speed is set to 0 mm / s, the riveting head position is locked and the clamping force is continuously applied, and the holding pressure time is maintained at 1-3 s.

[0009] Preferably, in step S5, comprehensive quality inspection, the inspection items include: S501, visual inspection: comprehensively inspect the riveting area for visible forming defects, and check for cracks, metal folds, missing material in the tooth groove, and extrusion deformation; S502, surface quality inspection: measure the surface roughness of the riveting end face with a testing instrument, and test the hardness of the spline tooth surface; S503, dimensional and positional inspection: use go / no-go gauges and gear measuring centers to check the various dimensions and positional tolerances of the workpiece; S504, non-destructive testing: use magnetic particle testing or penetrant testing to conduct flaw detection on the riveting pressure deformation area to detect fine hidden cracks on the surface of the workpiece.

[0010] Preferably, in step S1, the workpiece surface treatment, degreasing, derusting, and deburring operations are performed sequentially; wherein, oil stains are removed by wiping with organic solvents, dotted and flaky rust is removed by mechanical grinding, and radial and axial burrs generated by machining are chamfered and smoothed; after pretreatment, the surface roughness of the workpiece is controlled to Ra≤3.2μm.

[0011] Preferably, in the loading and positioning process of step S2, when the positioning fixture performs positioning, the inner raceway or outer race stop on the end face of the drive shaft housing is used as the positioning reference, and the positioning and clamping accuracy of the workpiece radial runout ≤0.02mm and end face runout ≤0.01mm is achieved by hydraulic or pneumatic clamping device.

[0012] Preferably, in step S4, the riveting forming, the riveting angle between the riveting head and the workpiece axis is determined based on the spline module m and the pitch circle diameter D, and the calculation formula is as follows: ,in, The riveting angle between the riveting head and the workpiece axis is denoted as . For correction coefficients, and Values ​​range from 1.2 to 1.5; In this context, θ is in degrees, and m and D use the same unit of length.

[0013] Preferably, in step S4, riveting, the total riveting pressure is based on the material's yield strength. Degree of deformation Calculate the forming pressure per unit area. Where p is the forming pressure per unit area, This is the correction value for the coefficient of friction, and The value should be between 1.5 and 2.5, with a 30% safety margin reserved for the total riveting pressure.

[0014] Preferably, in step S402, the workpiece forming stage, when the workpiece material is medium carbon steel, the value of the compression allowance δ is 0.1 to 0.2 mm; or when the workpiece material is alloy steel, the value of the compression allowance δ is 0.2 to 0.3 mm.

[0015] Preferably, in step S403, the pressure holding and shaping stage, when the workpiece material is medium carbon steel, the workpiece is pressure held for 1 to 2 seconds; or when the workpiece material is alloy steel, the workpiece is pressure held for 2 to 3 seconds.

[0016] Preferably, in step S504, non-destructive testing, magnetic particle testing or penetrant testing is used to perform 100% full inspection of the riveting deformation area and the stress concentration area at the tooth root of the workpiece.

[0017] Preferably, the steps described are applicable to the cold riveting of end face splines on drive shaft housings and wheel hub bearings, where the outer diameter of the end face splines is 50–150 mm.

[0018] This invention offers the following advantages: By employing a three-stage, graded control strategy—rapid approach, feed forming, and pressure holding—in the riveting process, the plastic flow of metal is precisely regulated. The rapid approach stage significantly reduces non-processing time and improves overall efficiency. The low-speed feed forming stage provides a stable and uniform extrusion environment, allowing the metal to fully and smoothly fill the grooves, effectively preventing cracks, material shortages, or uneven deformation caused by instantaneous high strain rates. The subsequent pressure holding stage, through continuous pressure and position maintenance, provides time for stress relaxation and structural stabilization, effectively counteracting the elastic recovery effect of the metal. Through the synergistic effect of the three-stage feed, high forming quality is ensured while processing efficiency is improved, ultimately resulting in end-face splines with high dimensional accuracy, good stability, and the ability to meet the high load-bearing requirements of the drive shaft housing. Detailed Implementation

[0019] The technical solutions in the embodiments of the present invention will be clearly and completely described below. 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.

[0020] The main objective of this application is to provide a cold riveting forming process for end face splines of drive shaft housings. This process addresses a series of technical problems inherent in existing cold riveting processes, which generally employ a single uniform feed mode. These problems result in an inability to balance processing efficiency and forming quality, leading to uneven workpiece deformation, poor tooth groove filling, poor dimensional stability of finished products, and high metal springback. This process is specifically designed for cold riveting forming of end face splines in drive shaft housings and wheel bearing components. It is applicable to end face spline outer diameters ranging from 50mm to 150mm and can be matched with industrial production scenarios of different materials, precision levels, and batch sizes. It exhibits strong versatility and adaptability. Commonly used materials include alloy structural steels such as 40Cr and 42CrMo. For wheel bearing components, specialized carburizing steel or bearing steel is selected. To ensure the workpiece's cold deformation capability and avoid excessive hardness leading to product cracking, the workpiece should be made of a material with a hardness of HB≥280HB and a surface roughness of not less than Ra3.2.

[0021] The complete set of production equipment used in implementing this process includes a workpiece conveying device, a mechanical handling arm, a dedicated positioning fixture, and a hydraulic or pneumatic clamping mechanism. The conveying device is responsible for transferring the workpiece; an automated handling arm is mounted on one side of the conveying device, which can accurately grasp the workpiece to be processed on the conveying device and smoothly clamp and transfer it into the positioning fixture at the riveting station. The positioning fixture can comprehensively limit and constrain the radial displacement of the workpiece, while rigidly locking the circumferential angle of the workpiece. This achieves bidirectional high-precision positioning of the workpiece, strictly limiting the coaxiality and circumferential angle deviation of the workpiece within the allowable range of the process. After limiting and locking, the radial runout of the workpiece is ≤0.02mm, and the circumferential runout is ≤0.01mm, thus avoiding problems such as workpiece offset, rotation, and wobble during riveting, and establishing a stable and reliable clamping datum for subsequent riveting extrusion and metal plastic forming operations.

[0022] The equipment is also equipped with a CNC cold riveting main unit, a riveting head assembly, and a spindle for driving the riveting head to complete rotation and lifting actions. After the spindle starts running, it drives the riveting head to rotate at high speed, and at the same time, it works with the lifting mechanism to drive the riveting head to move downward along the axis to extrude the end face of the workpiece. During the processing, the riveting head and the workpiece form a relative revolution rolling motion. Under the action of continuous and uniform compound extrusion force, the metal at the end of the workpiece undergoes controllable cold plastic flow. The metal material gradually fills and compacts into the tooth groove, and finally uniformly fills the entire tooth groove cavity, completing the riveting of the end face spline in one go.

[0023] The following section provides a complete description of the cold riveting forming process of the spline on the end face of the drive shaft housing in this application, based on the equipment structure and process principles.

[0024] A cold riveting forming process for the spline on the end face of a drive shaft housing includes the following steps: S1. Workpiece Surface Treatment: Clean the end face of the workpiece to be riveted, as well as the riveting pressure and end face spline pre-forming area. After treatment, check the surface cleanliness of the riveting area. This step is a preparatory process before riveting to avoid forming failures caused by unqualified raw materials or surface impurities. At the same time, check the material grade and product specifications of each workpiece.

[0025] In the preferred embodiment, the workpiece is sequentially subjected to degreasing, degreasing, rust removal, and deburring operations. Oil stains are removed by wiping with organic solvents, and dotted and flaky rust is removed by mechanical grinding. Radial and axial burrs generated during machining are chamfered and smoothed. After pretreatment, the surface roughness of the workpiece is controlled to Ra≤3.2μm. After cleaning, a designated person inspects the overall cleanliness of the riveting area, strictly requiring that the workpiece surface be free of residual oil film, rust pits, and sharp burrs generated during machining. This ensures that all mating surfaces of the workpiece are in close contact during the riveting operation, and that the cold-state riveting deformation of the metal is uniform and controllable throughout the process.

[0026] S2. Loading and positioning process: The workpiece to be riveted is smoothly transferred and placed in a special positioning fixture; relying on the inner raceway or outer ring stop of the wheel hub bearing as a reference, the radial limit constraint and circumferential angle locking of the workpiece are completed, realizing bidirectional high-precision positioning of the workpiece, limiting the coaxiality and circumferential rotation angle deviation of the workpiece within the allowable range of the process, avoiding workpiece offset and rotation during riveting, and providing a reliable clamping reference for subsequent riveting operations.

[0027] In a preferred embodiment, when the positioning fixture performs positioning, the inner raceway or outer stop of the drive shaft housing end face is used as the positioning reference. The positioning and clamping accuracy of the workpiece radial runout ≤0.02mm and end face runout ≤0.01mm is achieved by hydraulic or pneumatic clamping device. Thus, even under high extrusion pressure and long-term continuous processing conditions, the workpiece position will not be displaced during processing, ensuring the spline indexing accuracy and tooth profile consistency.

[0028] S3. Riveting Head Tool Setting and Calibration: After the workpiece is clamped, the riveting head tool setting and calibration process begins. The lifting mechanism carries the riveting head vertically downwards until the end of the riveting head is close to the workpiece's riveting end face. The equipment's built-in lifting mechanism drives the entire riveting head to move vertically downwards until the end of the riveting head is close to the workpiece's riveting end face, with a reasonable safety gap between them to avoid a hard collision between the riveting head and the workpiece during the downward movement, preventing damage to the mold and workpiece. The spinning angle is set according to the number of spline teeth and the tooth groove depth after the workpiece is formed. The operator, combining the total number of teeth and tooth groove depth of the workpiece after forming, accurately sets the spinning angle between the riveting head and the workpiece axis. After the parameters are set, the angle adjustment mechanism is locked, and the tool setting position and gap size are checked again. Only after confirming that everything is correct can the formal riveting process begin.

[0029] S4. Riveting Forming: The main shaft of the equipment starts and drives the riveting head to rotate. The riveting head slowly moves down along the axial direction to apply extrusion force to the workpiece. At the same time, the riveting head and the workpiece undergo relative revolution and rolling action. Under the continuous extrusion action, the metal at the end of the workpiece undergoes plastic flow, uniformly filling the tooth groove, and completing the riveting integral forming of the end face spline.

[0030] In a preferred embodiment, the riveting angle between the riveting head and the workpiece axis can be accurately calculated using a formula, which is: ,in, The riveting angle between the riveting head and the workpiece axis is denoted as . For correction coefficients, and The value is taken as 1.2 to 1.5; θ is in degrees, and m and D use the same unit of length. Based on actual production experience and considering the processing requirements of various specifications of spline workpieces, the tilt angle of the riveting head is generally controlled within the range of 15° to 30°. This angle range can ensure smooth metal flow and uniform rolling force.

[0031] At the same time, the total riveting pressure is precisely calculated based on the material properties of the workpiece, combined with the material's yield strength. Degree of deformation Calculate the forming pressure per unit area. Where p is the forming pressure per unit area, This is the correction value for the coefficient of friction, and The value should be between 1.5 and 2.5, with a 30% safety margin for the total riveting pressure. After calculating the theoretical total riveting pressure based on the pressure per unit area and the contact area, an additional 30% safety margin is reserved to cope with load fluctuations during processing and ensure the safe operation of the equipment and workpiece.

[0032] To address the drawbacks of the traditional single-feed mode, this process employs a three-stage, graded control for the axial feed of the riveting head spindle throughout the entire process. Different operating parameters are matched to each stage, balancing production efficiency and forming quality. Specifically, it is divided into three stages: S401, Rapid Approach Phase; The axial feed speed is uniformly set to 50-100 mm / s. The riveting head moves axially at high speed until it reaches a position 1-2 mm away from the workpiece end face, at which point the high-speed feed is immediately stopped. This stage is mainly used to shorten the idle travel time and improve the overall production cycle time.

[0033] S402, Infeed forming stage; The system automatically switches to low-speed feed mode, with the feed speed stably controlled between 0.5 and 2.0 mm / s. This stage is the core forming stage of the spline. The total axial feed displacement of the riveting head is equal to the sum of the spline design depth h and the compression allowance δ, where the compression allowance δ is generally taken in the range of 0.1 to 0.3 mm.

[0034] In a preferred embodiment, the compression allowance can be set according to the differences in workpiece material: when the workpiece material is medium carbon steel, the compression allowance δ is 0.1 to 0.2 mm; when the workpiece material is alloy steel with higher comprehensive strength, the compression allowance δ is 0.2 to 0.3 mm, matching the deformation characteristics of different materials to ensure that the tooth groove is fully filled and the forming dimensions are accurate.

[0035] S403, Pressure holding and shaping stage; The axial feed speed of the riveting head is set to 0 mm / s, the riveting head position is fully locked, and a static clamping force is continuously applied to the workpiece, with the overall pressure holding time maintained at 1–3 seconds. Continuous static pressure is used to suppress the elastic recovery of the metal after forming, stabilizing the dimensional and positional accuracy of the finished product.

[0036] In a preferred embodiment, the holding time can be differentiated based on the elastic properties of the material: when the workpiece material is medium carbon steel, the holding time is set to 1 to 2 seconds; when the workpiece material is alloy steel, because the elastic recovery of the material is greater, the holding time is set to 2 to 3 seconds to reduce and eliminate the dimensional deviation caused by springback.

[0037] After all three feed stages are completed, the lifting mechanism drives the riveting head to rise rapidly and return to the initial standby position, thus ending the single-workpiece riveting process.

[0038] S5. Comprehensive quality inspection; After the workpieces are riveted and formed, they are transferred to the quality inspection station for comprehensive quality inspection. This process implements full-process inspection control; only workpieces that pass all inspection items can be transferred to the next process such as assembly and warehousing. Workpieces deemed unqualified are uniformly labeled with defect tags, stored in separate areas, and then classified as rework parts or scrap parts according to defect type for further disposal. This process includes four parallel inspection items, as detailed below: S501, Visual inspection; Inspectors conduct a comprehensive visual inspection of the riveting and forming area, focusing on identifying various forming defects that can be seen with the naked eye. These defects mainly include surface cracks, metal folds, missing material in the tooth groove, local extrusion deformation, and flash. Workpieces with visual defects are directly judged as unqualified.

[0039] S502. Surface quality inspection: Inspection work is carried out with the help of professional testing instruments. The surface roughness of the riveted end face is measured with a surface roughness meter, and the hardness of the spline working tooth surface is tested with a hardness testing device. The measured data are compared with the process standards to ensure that the surface quality and mechanical properties meet the design requirements.

[0040] S503. Dimensional and positional inspection: Go / no-go gauges are used to quickly screen the basic dimensions of the spline. Then, precision equipment such as gear measuring centers are used to comprehensively inspect key dimensions and geometric tolerances such as the cumulative error of the tooth profile, tooth direction, and tooth pitch to ensure that the finished product meets the accuracy standards.

[0041] S504 Non-destructive testing uses either magnetic particle testing or penetrant testing to detect defects in the riveting deformation area, accurately identifying minute hidden cracks on the workpiece surface and preventing defective workpieces from flowing into downstream processes.

[0042] In the preferred embodiment, for key transmission components such as drive shaft housing and wheel hub bearing, the S504 non-destructive testing process is subject to 100% full inspection requirements. The inspection scope covers the riveting and deformation areas of the workpiece and the tooth root where stress concentration is most obvious, so as to comprehensively control the internal quality of the product and improve the reliability and service life of the components. In some embodiments, for defect detection The workpiece is considered to be of acceptable quality if its appearance is observed visually or with a 5x magnifying glass and there are no cracks, folds, scratches, under-pressure, or burrs on the surface. The tooth profile accuracy is measured using a gear measuring center or CMM, and the tooth profile error is ≤0.02mm, and the tooth direction error is ≤0.015mm. The cumulative pitch difference measured using a gear measuring center should achieve an accuracy of grade 8 or higher (including grade 8) according to the national standard GB / T 10095.1. The surface roughness was measured using a profilometer, and the surface roughness Ra ≤ 1.6 μm; The surface hardness was measured using a Vickers hardness tester, and its surface hardness HV≥280.

[0043] Those skilled in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of the invention (including the claims) is limited to these examples; within the framework of the invention, the technical features of the above embodiments or different embodiments can also be combined, the order of some auxiliary steps can be adjusted without violating the process logic, and there are many other variations of different aspects of the invention as described above, which are not provided in the details for the sake of brevity.

[0044] This invention is intended to cover all such substitutions, modifications, and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A cold riveting forming process for the spline on the end face of a drive shaft housing, characterized in that, Includes the following steps: S1. Workpiece surface treatment: Clean the end face of the workpiece to be riveted, as well as the riveting pressure and end face spline pre-forming area. After treatment, check the surface cleanliness of the riveting area. S2. Loading and positioning process: The workpiece to be riveted is smoothly transferred and placed into a special positioning fixture; the positioning fixture completes the radial limit constraint and circumferential angle locking of the workpiece, realizing bidirectional high-precision positioning of the workpiece. After the limit is locked, the radial runout of the workpiece is ≤0.02mm and the circumferential runout is ≤0.01mm. S3. Riveting head tool setting and calibration: The lifting mechanism carries the riveting head vertically downward until the end of the riveting head is close to the end face of the workpiece to be riveted; and the riveting angle is set according to the number of spline teeth and the tooth groove depth after the workpiece is formed. S4. Riveting Forming: The main shaft of the equipment starts and drives the riveting head to rotate. The riveting head slowly moves down along the axial direction to apply extrusion force to the workpiece. At the same time, the riveting head and the workpiece undergo relative revolution and rolling action. Under the continuous extrusion action, the metal at the end of the workpiece undergoes plastic flow, uniformly filling the tooth groove and completing the riveting integral forming. S5. Comprehensive quality inspection: Non-conforming workpieces are individually marked and isolated. In step S4, the riveting process, the feed process of the riveting head spindle adopts a three-stage graded control, which includes the following steps: S401, Rapid Approach Stage: The axial feed speed is set to 50-100 mm / s. The riveting head quickly moves to a position 1-2 mm away from the end face of the workpiece and then stops the high-speed feed. S402, Working feed stage: Switch to low-speed feed mode, and control the feed speed between 0.5 and 2.0 mm / s. The total axial feed displacement is the sum of the spline design depth h and the compression allowance δ, where the compression allowance δ is 0.1 to 0.3 mm. S403, Pressure Holding and Shaping Stage: Set the axial feed speed to 0 mm / s, lock the riveting head position and continuously apply clamping force, and maintain the pressure holding time for 1 to 3 seconds.

2. The cold riveting forming process for the spline on the end face of a drive shaft housing according to claim 1, characterized in that, In step S5, the comprehensive quality inspection, the inspection items include: S501. Visual inspection: For visible forming defects, conduct a comprehensive inspection of the riveted parts to check for cracks, metal folds, missing material in the tooth grooves, and extrusion deformation. S502 Surface quality inspection: Use testing instruments to determine the surface roughness of the riveted end face and test the hardness of the spline tooth surface; S503, Dimensional and Geometric Inspection: Use go / no-go gauges and gear measuring centers to inspect the various dimensions and geometric tolerances of the workpiece; S504. Non-destructive testing: Magnetic particle testing or penetrant testing is used to conduct flaw detection on the riveting pressure deformation area to detect minute hidden cracks on the surface of the workpiece.

3. The cold riveting forming process for the spline on the end face of a drive shaft housing according to claim 1, characterized in that, In step S1, the workpiece surface treatment, degreasing, derusting, and deburring operations are performed sequentially. Oil stains are removed by wiping with organic solvents, spot and flaky rust are removed by mechanical grinding, and radial and axial burrs produced by machining are chamfered and smoothed. After pretreatment, the surface roughness of the workpiece is controlled to Ra≤3.2μm.

4. The cold riveting forming process for the spline on the end face of a drive shaft housing according to claim 1, characterized in that, In the loading and positioning process of step S2, when the positioning fixture is positioned, the inner raceway or outer race stop on the end face of the drive shaft housing is used as the positioning reference, and the positioning and clamping accuracy of the workpiece radial runout ≤0.02mm and end face runout ≤0.01mm is achieved by hydraulic or pneumatic clamping device.

5. The cold riveting forming process for the spline on the end face of a drive shaft housing according to claim 1, characterized in that, In step S4, the riveting process, the riveting angle between the riveting head and the workpiece axis is determined based on the spline module m and the pitch circle diameter D, and the calculation formula is as follows: ,in, The riveting angle between the riveting head and the workpiece axis is denoted as . For correction factors, and Values ​​range from 1.2 to 1.5; In this context, θ is in degrees, and m and D use the same unit of length.

6. The cold riveting forming process for the spline on the end face of a drive shaft housing according to claim 1, characterized in that, In step S4, riveting, the total riveting pressure is based on the material's yield strength. Degree of deformation Calculate the forming pressure per unit area. Where p is the forming pressure per unit area, This is the correction value for the coefficient of friction, and The value should be between 1.5 and 2.5, with a 30% safety margin reserved for the total riveting pressure.

7. The cold riveting forming process for the spline on the end face of a drive shaft housing according to claim 1, characterized in that, In step S402, the feed forming stage, when the workpiece material is medium carbon steel, the compression allowance δ is 0.1–0.2 mm; or, When the workpiece material is alloy steel, the compression allowance δ is 0.2 to 0.3 mm.

8. The cold riveting forming process for the spline on the end face of a drive shaft housing according to claim 1, characterized in that, In step S403, the pressure holding and shaping stage, when the workpiece material is medium carbon steel, the workpiece is held under pressure for 1-2 seconds; or, When the workpiece is made of alloy steel, the workpiece is held under pressure for 2 to 3 seconds.

9. The cold riveting forming process for the spline on the end face of a drive shaft housing according to claim 2, characterized in that, In step S504, non-destructive testing, magnetic particle testing or penetrant testing is used to perform 100% full inspection of the riveting deformation area and the stress concentration area at the tooth root of the workpiece.

10. The cold riveting forming process for the spline on the end face of a drive shaft housing according to claim 1, characterized in that, The steps described are applicable to the cold riveting of end face splines on drive shaft housings and wheel hub bearings, with an outer diameter of 50-150 mm.