Machining method for outer rings of medium-large thin-wall tapered roller bearings

Abstract

The invention discloses a method for machining outer rings of medium-large thin-wall tapered roller bearings, and relates to the field of methods for machining outer rings of medium-large thin-wall tapered roller bearings. The invention aims to solve the technical problems of poor processing quality and high rejection rate of the current processing method of the medium-large thin-wall tapered roller bearing. The method comprises the following steps: 1, turning one side end surface and outer and inner diameter surfaces of a workpiece; secondly, turning the end face and the outer diameter face of the other side of the workpiece; 3, processing a raceway and an inner side chamfer; heat treatment; fifthly, end face allowance is removed, and end face taper deformation generated by heat treatment is modified; 6, finishing deformation of the outer diameter surface of the workpiece treated in the step 5; seventhly, a roller path is subjected to hard turning; 8, stabilizing treatment; and 9, performing fine grinding, final grinding and fine grinding treatment. According to the method, the size and precision of the outer ring of the medium-large thin-wall tapered roller bearing are effectively guaranteed, and the rejection rate is reduced. The method is used for machining the outer rings of the medium-large thin-wall tapered roller bearings.

Description

Technical Field

[0001] The invention relates to the field of methods for processing outer rings of medium and large thin-walled tapered roller bearings. Background Art

[0002] The outer ring of medium and large thin-walled tapered roller bearings is characterized by a tapered raceway, thin product wall, and a large difference in wall thickness at both ends. It is easy to produce clamping deformation during lathe processing. After heat treatment, the expansion and contraction of the large and small end faces are inconsistent, resulting in the ring taper deformation and the change in the outer diameter of a single plane that is difficult to control. Once the deformation is large and exceeds the allowance range for grinding, the dimensional accuracy of the ring is unqualified, resulting in scrap. However, if the allowance is greatly increased in order to change the deformation, although the dimensional accuracy can be guaranteed, the grinding difficulty and processing time are increased. Summary of the invention

[0003] The invention provides a method for processing the outer ring of a medium-sized and large thin-walled tapered roller bearing in order to solve the technical problems of poor processing quality and high scrap rate in the current processing method of the medium-sized and large thin-walled tapered roller bearing.

[0004] The outer ring processing method of medium and large thin-walled tapered roller bearings is carried out in the following steps:

[0005] 1. Turn the end face and outer inner diameter surface of the workpiece, and leave 0.3-0.4mm for the raceway on the outer inner diameter surface;

[0006] 2. Clamping step 1: Process the end face and outer inner diameter surface of the workpiece, turn the end face and outer diameter surface of the other side of the workpiece, control the allowance of the end face to be 0.7-0.8mm, and the allowance of the outer diameter surface to be 0.7-0.8mm;

[0007] 3. Clamping step 2: Process one side end face and outer diameter surface of the workpiece, process the raceway and inner chamfer, and control the raceway allowance to be 1.45-1.55mm;

[0008] 4. heat treating the workpiece processed in step 3;

[0009] 5. Remove the end face allowance of the workpiece processed in step 4 and modify the end face taper deformation caused by heat treatment;

[0010] 6. Taking the end face as the reference, the outer diameter surface deformation of the workpiece is processed in step 5 of the dressing process;

[0011] 7. Using the end face ground in step 5 and the outer diameter face trimmed in step 6 as the clamping reference, hard turn the workpiece;

[0012] 8. Stabilize the workpiece processed in step 7;

[0013] 9. Finely grind, final grind and finely grind the outer diameter and outer raceway of the workpiece processed in step 8 to complete.

[0014] Step 1: Leave raceway machining allowance when turning the outer inner diameter surface. Do not directly machine to the raceway size. The outer inner diameter surface is only used as a clamping reference. Its dimensional tolerance range and accuracy must be controlled as much as possible to provide accuracy reserve for machining the outer diameter surface.

[0015] Step 2: Control the processing parameters to reduce cutting stress and prevent greater deformation caused by stress release during heat treatment.

[0016] Compared with the rough grinding of the raceway used in previous processing, the method of hard turning instead of rough grinding in step seven not only improves the processing efficiency but also avoids the problem of grinding burns that may be caused by multiple grindings with too large a stock.

[0017] When grinding the end face and outer diameter surface, if the machining allowance is too large, the method of hard turning first and then grinding can be used to appropriately improve the machining efficiency.

[0018] Beneficial effects of the present invention:

[0019] A method for processing the outer ring of a medium-to-large thin-walled tapered roller bearing is provided, which can effectively improve the overall quality of the outer ring and the first-time inspection pass rate.

[0020] The present invention can solve the technical problem of low surface precision caused by large deformation of the ring after heat treatment by optimizing the process flow and reserve of the outer ring of medium and large thin-walled tapered roller bearings, so that the size and precision of the outer ring of the medium and large thin-walled tapered roller bearings are effectively guaranteed and the scrap rate is reduced.

[0021] The invention is used for processing the outer ring of medium and large thin-walled tapered roller bearings. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 A schematic diagram of a product obtained by processing in an embodiment;

[0023] Figure 2 This is a schematic diagram of a workpiece after processing in step 1 of the embodiment. DETAILED DESCRIPTION

[0024] Specific implementation method 1: In this implementation method, the outer ring processing method of a large thin-walled tapered roller bearing is specifically carried out according to the following steps:

[0025] 1. Turn the end face and outer inner diameter surface of the workpiece, and leave 0.3-0.4mm for the raceway on the outer inner diameter surface;

[0026] 2. Clamping step 1: Process the end face and outer inner diameter surface of the workpiece, turn the end face and outer diameter surface of the other side of the workpiece, control the allowance of the end face to be 0.7-0.8mm, and the allowance of the outer diameter surface to be 0.7-0.8mm;

[0027] 3. Clamping step 2: Process one side end face and outer diameter surface of the workpiece, process the raceway and inner chamfer, and control the raceway allowance to be 1.45-1.55mm;

[0028] 4. heat treating the workpiece processed in step 3;

[0029] 5. Remove the end face allowance of the workpiece processed in step 4 and modify the end face taper deformation caused by heat treatment;

[0030] 6. Taking the end face as the reference, the outer diameter surface deformation of the workpiece is processed in step 5 of the dressing process;

[0031] 7. Using the end face ground in step 5 and the outer diameter face trimmed in step 6 as the clamping reference, hard turn the workpiece;

[0032] 8. Stabilize the workpiece processed in step 7;

[0033] 9. Finely grind, final grind and finely grind the outer diameter and outer raceway of the workpiece processed in step 8 to complete.

[0034] Specific implementation method 2: This implementation method is different from specific implementation method 1 in that: in step 3, the cutting speed V is controlled to be 80 m / min, the cutting depth ap is controlled to be 0.5 mm, and the feed rate is controlled to be 0.15 mm / rev. The rest is the same as specific implementation method 1.

[0035] Specific implementation method 3: This implementation method is different from specific implementation method 1 or 2 in that the heat treatment process in step 4 is quenching treatment, first tempering treatment, cold treatment, second tempering treatment, and third tempering treatment. The rest is the same as specific implementation method 1 or 2.

[0036] Specific embodiment 4: This embodiment is different from specific embodiments 1 to 3 in that the quenching temperature is 850° C. and the time is 30 minutes. The rest is the same as specific embodiments 1 to 3.

[0037] Specific embodiment 5: This embodiment is different from specific embodiments 1 to 4 in that the treatment temperature of the first tempering treatment, the second tempering treatment and the third tempering treatment are all 500° C. and the treatment time is all 120 minutes. The rest is the same as specific embodiments 1 to 4.

[0038] Specific implementation method 6: This implementation method is different from specific implementation methods 1 to 5 in that: in step 5, an end face grinder is used to process the workpiece. The rest is the same as specific implementation methods 1 to 5.

[0039] Specific implementation method 7: This implementation method is different from specific implementation methods 1 to 6 in that: in step 6, an outer diameter grinder is used to process the workpiece. The rest is the same as specific implementation methods 1 to 6.

[0040] Specific embodiment 8: This embodiment is different from specific embodiments 1 to 7 in that: when trimming the outer diameter surface deformation in step 6, the ovality VDsp is controlled to be ≤ 0.15 mm and the prism degree 2ΔCir is controlled to be ≤ 0.15 mm. The rest is the same as specific embodiments 1 to 7.

[0041] Specific embodiment 9: This embodiment is different from specific embodiments 1 to 8 in that the hard turning parameters in step 7 are: cutting speed V is 80-100 m / min, cutting depth ap≤0.5 mm, and feed rate is 0.05-0.1 mm / rev. Others are the same as specific embodiments 1 to 8.

[0042] Specific embodiment 10: This embodiment differs from specific embodiments 1 to 9 in that the stabilization treatment temperature in step 8 is 500° C. and the treatment time is 30 hours. The rest is the same as specific embodiments 1 to 9.

[0043] The content of the present invention is not limited to the content of the above-mentioned embodiments. The combination of one or several specific embodiments can also achieve the purpose of the invention.

[0044] Example:

[0045] The method for processing the outer ring of a large thin-walled tapered roller bearing in this embodiment is specifically carried out in the following steps:

[0046] 1. Turn the end face and outer inner diameter surface of the workpiece, and leave 0.3-0.4mm for the raceway on the outer inner diameter surface;

[0047] 2. Clamping step 1: Process the end face and outer inner diameter surface of the workpiece, turn the end face and outer diameter surface of the other side of the workpiece, control the allowance of the end face to be 0.7-0.8mm, and the allowance of the outer diameter surface to be 0.7-0.8mm;

[0048] 3. Clamping step 2: Process one side end face and outer diameter face of the workpiece, process the raceway and inner chamfer, control the cutting speed V to 80m / min, the cutting depth ap to 0.5mm, the feed rate to 0.15mm / rev, and the raceway allowance to 1.45-1.55mm;

[0049] 4. The workpiece treated in step 3 is heat treated, and the heat treatment process is quenching treatment, first tempering treatment, cold treatment, second tempering treatment, and third tempering treatment. The quenching temperature is 850°C and the time is 30 minutes. The treatment temperatures of the first tempering treatment, the second tempering treatment, and the third tempering treatment are all 500°C and the time is 120 minutes.

[0050] 5. Use an end face grinder to remove the end face allowance of the workpiece processed in step 4 and modify the end face taper deformation caused by heat treatment;

[0051] 6. Using the outer diameter grinder and taking the end face as the reference, the outer diameter surface deformation of the workpiece is processed in step 5 to control the ovality VDsp≤0.15mm and the facet degree 2△Cir≤0.15mm;

[0052] 7. Using the end face ground in step 5 and the outer diameter face trimmed in step 6 as the clamping reference, the workpiece is hard turned into a raceway; the hard turning parameters are: cutting speed V is 80-100m / min, cutting depth ap≤0.5mm, and feed rate is 0.05-0.1mm / rev;

[0053] 8. Stabilize the workpiece processed in step 7 at a temperature of 500°C for 30 hours;

[0054] 9. Finely grind, final grind and finely grind the outer diameter and outer raceway of the workpiece processed in step 8 to complete.

[0055] Figure 1 A schematic diagram of a product obtained by processing in an embodiment;

[0056] Figure 2 This is a schematic diagram of a workpiece after processing in step 1 of the embodiment.

[0057] The present invention can solve the technical problem of low surface precision caused by large deformation of the ring after heat treatment by optimizing the process flow and reserve of the outer ring of medium and large thin-walled tapered roller bearings, so that the size and precision of the outer ring of the medium and large thin-walled tapered roller bearings are effectively guaranteed and the scrap rate is reduced.

Claims

1. The outer ring processing method of medium and large thin-walled tapered roller bearings is characterized by The method is specifically carried out in the following steps:

1. Turn the end face and outer inner diameter surface of the workpiece, and leave 0.3-0.4mm for the raceway on the outer inner diameter surface; 2. Clamping step 1: Process the end face and outer inner diameter surface of the workpiece, turn the end face and outer diameter surface of the other side of the workpiece, control the allowance of the end face to be 0.7-0.8mm, and the allowance of the outer diameter surface to be 0.7-0.8mm; 3. Clamping step 2: Process one side end face and outer diameter surface of the workpiece, process the raceway and inner chamfer, and control the raceway allowance to be 1.45-1.55mm; 4. heat treating the workpiece processed in step 3; 5. Remove the end face allowance of the workpiece processed in step 4 and modify the end face taper deformation caused by heat treatment; 6. Taking the end face as the reference, the outer diameter surface deformation of the workpiece is processed in step 5 of the dressing process; 7. Using the end face ground in step 5 and the outer diameter face trimmed in step 6 as the clamping reference, hard turn the workpiece; 8. Stabilize the workpiece processed in step 7; 9. Finely grind, final grind and finely grind the outer diameter and outer raceway of the workpiece processed in step 8 to complete.

2. The method for processing the outer ring of a medium-to-large thin-walled tapered roller bearing according to claim 1, characterized in that Step 3: Control the cutting speed V to 80 m / min, the cutting depth ap to 0.5 mm, and the feed rate to 0.15 mm / rev.

3. The method for processing the outer ring of a medium-to-large thin-walled tapered roller bearing according to claim 1, characterized in that The heat treatment process in step 4 is quenching, first tempering, cold treatment, second tempering and third tempering.

4. The method for processing the outer ring of a medium-to-large thin-walled tapered roller bearing according to claim 3, characterized in that The quenching temperature is 850℃ and the time is 30min.

5. The method for processing the outer ring of a medium-to-large thin-walled tapered roller bearing according to claim 3, characterized in that The treatment temperatures of the first tempering treatment, the second tempering treatment and the third tempering treatment are all 500°C and the treatment time is all 120 minutes.

6. The method for processing the outer ring of a medium-to-large thin-walled tapered roller bearing according to claim 1, characterized in that Step 5: Use end face grinder to process the workpiece.

7. The method for processing the outer ring of a medium-to-large thin-walled tapered roller bearing according to claim 1, characterized in that Step 6: Use an external diameter grinder to process the workpiece.

8. The method for processing the outer ring of a medium-to-large thin-walled tapered roller bearing according to claim 1, characterized in that Step 6: When trimming the outer diameter surface deformation, control the ovality VDsp≤0.15mm and the prism degree 2△Cir≤0.15mm.

9. The method for processing the outer ring of a medium-to-large thin-walled tapered roller bearing according to claim 1, characterized in that Step seven hard turning parameters are: cutting speed V is 80-100 m / min, cutting depth ap≤0.5 mm, and feed rate is 0.05-0.1 mm / rev.

10. The method for processing the outer ring of a medium-to-large thin-walled tapered roller bearing according to claim 1, characterized in that The stabilization treatment temperature in step eight is 500° C. and the time is 30 hours.

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