A method for solving the adhesion of the bottom die of the automatic forging of the bearing ring
By designing punching dies and controlling the thickness of the connecting skin, the problem of skin adhesion at the bottom-cutting punch in the automated forging of bearing rings was solved, achieving efficient automated production and improved safety.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- HARBIN INST OF TECH
- Filing Date
- 2024-04-02
- Publication Date
- 2026-07-31
AI Technical Summary
In the automated forging process of bearing rings, the bottom-cutting punch is prone to sticking to the outer layer, which leads to a decrease in forming quality and poses a safety hazard. Existing technologies are unable to effectively solve this problem.
Design a punching die, including an upper punching die, a lower punching die, and an outer die sleeve. The end face of the punching punch is provided with a transition rounded corner, the thickness of the connecting skin is controlled to be 4mm to 6mm, and the connecting skin is removed by a bottom-cutting and hole-expanding punch to ensure that the connecting skin does not cover the punch during bottom cutting.
This effectively avoids the adhesion of the bottom-cutting punch, improves the forming quality of the bearing rings, reduces safety risks, and meets the production needs of automated forging.
Smart Images
Figure CN118341932B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of bearing ring forging. Background Technology
[0002] The shift from manual free forging to automated forging in the production of bearing rings has placed more stringent demands on the manufacturing process. Manual free forging allows for manual control, and issues such as material adhesion or die sticking can be resolved by manual striking. However, automated forging of bearing rings is constrained by production cycle time, requiring a tight forging process and preventing foreign matter from adhering to the die. This presents new challenges to the bearing ring forging process.
[0003] The existing automated forging process for bearing rings involves upsetting, punching, undercutting, reaming, and rolling. During undercutting, a problem arises where the punch adheres to the die. If this tattered material is not removed before cutting the next blank, it significantly impacts the forming quality of the bearing ring. In traditional manual forging, this tattered material can be removed manually by hammering. However, in automated forging, due to the fixed production cycle, manual removal of the tattered material could damage the blank and die, posing a significant safety hazard to workers. Therefore, an efficient method for resolving the issue of punch adhesion during the undercutting process is urgently needed in automated forging of bearing rings. Summary of the Invention
[0004] This invention aims to solve the problem of skin adhesion of the bottom-cutting punch during the bottom-cutting process in existing automated forging of bearing rings, and further provides a method for solving the skin adhesion problem of the bottom-cutting die in automated forging of bearing rings.
[0005] A method for resolving the adhesion of the bottom cutting die in automated forging of bearing rings comprises the following steps:
[0006] I. Punching Die Design:
[0007] The punching die consists of an upper punching die, a lower punching die, and an outer die sleeve; the inner surface of the outer die sleeve is tapered.
[0008] The upper and lower punching dies are both provided with punching punches of the same shape and size in the middle; the end face of the punching punch is provided with a transition fillet, which is a rounded chamfer, a straight line segment and an elliptical chamfer from the end face upwards;
[0009] Let the end diameter of the punch be d; let the radius of the chamfer be r; let the major axis of the elliptical chamfer be r1 and the minor axis be r2; when 25mm≤d≤50mm, r=3mm~5mm, r1=3.5mm~5.5mm, r2=2mm~3.5mm; when 50mm<d≤100mm, r=5mm~10mm, r1=5.5mm~11mm, r2=3.5mm~7mm; when 100mm<d≤200mm, r=10mm~20mm, r1=5mm~22mm, r2=7mm~14mm;
[0010] II. Controlling the thickness of the skin:
[0011] The lower punching die and the bearing ring blank are placed inside the outer die sleeve from bottom to top. Then the upper punching die is pressed down to punch the bearing ring blank to obtain a blank with a connecting skin.
[0012] The punched skin of the billet with connected skin is located in the middle of the billet, and the thickness of the punched skin is 4mm to 6mm.
[0013] III. Automated forging and bottom cutting of bearing rings:
[0014] The method of removing the sticky skin from the punched blank with the connecting skin in the automated forging die of bearing rings is completed by using a bottom-cutting and hole-expanding punch.
[0015] The beneficial effects of this invention are:
[0016] This invention controls the thickness of the punching skin to ensure that during bottom cutting, the punching skin will not deform too much and wrap around the bottom cutting punch due to being too thin, nor will it wrap around the bottom cutting punch due to being too thick.
[0017] This invention designs the punch structure of the punching die to provide a reasonable transition for the rounded corners of the punched skin; when the bottom-cutting punch contacts the skin, the elliptical shape of the skin edge has a large angle with the punch, which relatively reduces the material content in a certain space around the bottom-cutting punch and reduces the risk of the skin covering the punch during cutting.
[0018] This invention addresses the problem of the cutting punch sticking to the outer skin during the bottom cutting process in automated forging of bearing rings.
[0019] This invention relates to a method for solving the problem of skin adhesion in the bottom cutting die of automated forging of bearing rings. Attached Figure Description
[0020] Figure 1 This is a schematic diagram of the automated forging and cutting of the bearing rings in step three of the present invention.
[0021] Figure 2 This is a three-dimensional schematic diagram of the punching die described in step one of the present invention;
[0022] Figure 3 This is a schematic diagram of the punching upper die described in step one of the present invention;
[0023] Figure 4 This is a schematic diagram of the structure of the outer mold sleeve described in step one of the present invention;
[0024] Figure 5 For comparison, here is a schematic diagram of the transition fillet of the punch described in step one of the experiment.
[0025] Figure 6 This is a schematic diagram of the transition fillet of the punch described in step one of the present invention;
[0026] Figure 7 For comparison, images of the sticking skin of the punch after bottom cutting and hole enlargement were taken.
[0027] Figure 8 For comparison, images of the skin cut off after the bottom was cut were taken.
[0028] Figure 9 This is an image of the skin that was cut off after the bottom of the sample was cut open, as shown in the example. Detailed Implementation
[0029] The technical solution of the present invention is not limited to the specific embodiments listed below, but also includes any combination of the specific embodiments.
[0030] Specific implementation method one: Combining Figures 1 to 4 6. Specific Explanation: This embodiment provides a method for solving the problem of skin adhesion in automated forging and bottom cutting dies for bearing rings. It is carried out according to the following steps:
[0031] I. Punching Die Design:
[0032] The punching die consists of an upper punching die, a lower punching die, and an outer die sleeve; the inner surface of the outer die sleeve is tapered.
[0033] The upper and lower punching dies are both provided with punching punches of the same shape and size in the middle; the end face of the punching punch is provided with a transition fillet, which is a rounded chamfer, a straight line segment and an elliptical chamfer from the end face upwards;
[0034] Let the end diameter of the punch be d; let the radius of the chamfer be r; let the major axis of the elliptical chamfer be r1 and the minor axis be r2; when 25mm≤d≤50mm, r=3mm~5mm, r1=3.5mm~5.5mm, r2=2mm~3.5mm; when 50mm<d≤100mm, r=5mm~10mm, r1=5.5mm~11mm, r2=3.5mm~7mm; when 100mm<d≤200mm, r=10mm~20mm, r1=5mm~22mm, r2=7mm~14mm;
[0035] II. Controlling the thickness of the skin:
[0036] The lower punching die and the bearing ring blank are placed inside the outer die sleeve from bottom to top. Then the upper punching die is pressed down to punch the bearing ring blank to obtain a blank with a connecting skin.
[0037] The punched skin of the billet with connected skin is located in the middle of the billet, and the thickness of the punched skin is 4mm to 6mm.
[0038] III. Automated forging and bottom cutting of bearing rings:
[0039] The method of removing the sticky skin from the punched blank with the connecting skin in the automated forging die of bearing rings is completed by using a bottom-cutting and hole-expanding punch.
[0040] The beneficial effects of this embodiment are:
[0041] This embodiment controls the thickness of the punching skin to ensure that during bottom cutting, the punching skin will not deform too much and wrap around the bottom cutting punch due to being too thin, nor will it wrap around the bottom cutting punch due to being too thick.
[0042] This embodiment designs the punch structure of the punching die to provide a reasonable transition for the rounded corners of the punched skin; when the bottom-cutting punch contacts the skin, the elliptical shape of the skin edge has a large angle with the punch, which relatively reduces the material content in a certain space around the bottom-cutting punch and reduces the risk of the skin covering the punch during cutting.
[0043] This embodiment is used to solve the problem of the bottom cutting punch sticking to the skin during the bottom cutting process in the automated forging of bearing rings.
[0044] Specific Implementation Method Two: This implementation method differs from Specific Implementation Method One in that the taper of the inner surface of the outer mold sleeve is set to γ in step one, where γ = 2° to 6°. Everything else is the same as in Specific Implementation Method One.
[0045] Specific Implementation Method Three: This implementation method differs from Specific Implementation Method One or Two in that: let the height of the bearing ring blank in step two be H, and let the effective height of the outer mold sleeve in step one be h, then h = H + 6mm. Everything else is the same as Specific Implementation Method One or Two.
[0046] Specific Implementation Method Four: This implementation method differs from Specific Implementation Methods One to Three in that: the maximum outer diameter of the bearing ring blank in step two is set to D, and the inner diameter of the small end of the outer mold sleeve in step one is set to φ, where φ = D + 2mm. Everything else is the same as in Specific Implementation Methods One to Three.
[0047] Specific Implementation Method Five: This implementation method differs from Specific Implementation Methods One to Four in that: the height of the punch in step one is set to h1, where h1 = [H - (3mm ~ 7mm)] / 2. Everything else is the same as in Specific Implementation Methods One to Four.
[0048] Specific Implementation Method Six: This implementation method differs from Specific Implementation Methods One to Five in that: the taper of the punch in step one is set to α, where 20°≤α≤30°. Everything else is the same as in Specific Implementation Methods One to Five.
[0049] Specific Implementation Method Seven: This implementation method differs from Specific Implementation Methods One to Six in that: the circle containing the round chamfer in step one is tangent to the end face of the punch, and the ellipse containing the elliptical chamfer is tangent to the side wall of the punch; the straight line segment is located between the round chamfer and the elliptical chamfer, and is tangent to both the round chamfer and the elliptical chamfer respectively. Everything else is the same as in Specific Implementation Methods One to Six.
[0050] Specific Implementation Method Eight: This implementation method differs from Specific Implementation Methods One to Seven in that the bearing ring blank mentioned in step two is a upset disc-shaped blank. Everything else is the same as in Specific Implementation Methods One to Seven.
[0051] Specific Implementation Method Nine: This implementation method differs from Specific Implementation Methods One to Eight in that: the height of the blank with skin in step two is set to h2, where H-1mm≤h2≤H+1mm. Everything else is the same as in Specific Implementation Methods One to Eight.
[0052] Specific Implementation Method Ten: This implementation method differs from Specific Implementation Methods One to Nine in that the diameter of the bottom-cutting and hole-enlarging punch described in step three is the same as the diameter of the punch described in step one, and the end face of the bottom-cutting and hole-enlarging punch has no chamfer. Everything else is the same as Specific Implementation Methods One to Nine.
[0053] The beneficial effects of the present invention are verified using the following embodiments:
[0054] Example 1: A bearing ring part with an inner diameter of 140mm, a height of 35mm, and an outer diameter of 160mm is pre-prepared. A method for resolving the adhesion of the die in the automated forging and cutting process of the bearing ring is then implemented, following these steps:
[0055] I. Punching Die Design:
[0056] The punching die consists of an upper punching die, a lower punching die, and an outer die sleeve; the inner surface of the outer die sleeve is tapered.
[0057] The upper and lower punching dies are both provided with punching punches of the same shape and size in the middle; the end face of the punching punch is provided with a transition fillet, which is a rounded chamfer, a straight line segment and an elliptical chamfer from the end face upwards;
[0058] Let the end diameter of the punch be d, d = 26 mm; let the radius of the rounded chamfer be r; let the major semi-axis of the elliptical chamfer be r1, and the minor semi-axis be r2; r = 3 mm, r1 = 3.5 mm, r2 = 2 mm;
[0059] II. Controlling the thickness of the skin:
[0060] The lower punching die and the bearing ring blank are placed inside the outer die sleeve from bottom to top. Then the upper punching die is pressed down to punch the bearing ring blank to obtain a blank with a connecting skin.
[0061] The punched skin of the billet with skin is located in the middle of the billet, and the thickness of the punched skin is 5mm.
[0062] III. Automated forging and bottom cutting of bearing rings:
[0063] Under the condition of billet temperature of 1100℃, the punching and connecting skin in the billet with connecting skin is removed by using a bottom-cutting and hole-expanding punch, thus completing the method of solving the problem of the sticking skin of the bottom-cutting die in the automated forging of bearing rings.
[0064] In step one, the taper of the inner surface of the outer mold sleeve is set to γ, where γ = 2°.
[0065] Let the height of the bearing ring blank in step two be H, where H = 50 mm; and let the effective height of the outer mold sleeve in step one be h, then h = H + 6 mm = 56 mm.
[0066] Let the maximum outer diameter of the bearing ring blank in step two be D, where D = 120 mm, and let the inner diameter of the small end of the outer mold sleeve in step one be φ, where φ = D + 2 mm = 122 mm.
[0067] Let the height of the punch in step one be h1, h1 = (H - 6mm) / 2 = 22mm.
[0068] Let the taper of the punch in step one be α, where α = 26°.
[0069] In step one, the circle containing the round chamfer is tangent to the end face of the punch, and the ellipse containing the ellipse is tangent to the side wall of the punch; the straight line segment is located between the round chamfer and the ellipse chamfer, and is tangent to both the round chamfer and the ellipse chamfer respectively.
[0070] The bearing ring blank mentioned in step two is a cake-shaped blank after upsetting.
[0071] Let the height of the blank with skin in step two be h2, h2 = 49mm.
[0072] The diameter of the bottom-cutting and hole-expanding punch described in step three is the same as the diameter of the punch described in step one, and the end face of the bottom-cutting and hole-expanding punch has no chamfer.
[0073] The bearing ring blank material mentioned in step two is 8Cr4Mo4V.
[0074] Compared with Experiment 1, combined Figure 5 Specific details: This comparative experiment differs from Example 1 in the following ways: The height of the punch in step one is set to h1, where h1 = (H - 12mm) / 2 = 19mm; the thickness of the punch skin in step two is 11mm; and the end face of the punch in step one is provided with a transition fillet, which is a rounded chamfer with a radius of 3mm. Everything else is the same as in Example 1.
[0075] Figure 7 To compare the images of the punch sticking to the bottom after cutting and enlarging the hole in the experiment; as can be seen from the circled position in the image, the sticking skin adhered to the punch and returned to the initial position along with the punch.
[0076] Figure 8 For comparison, images of the skin cut off after the bottom of the test are shown. It can be seen that there are burrs perpendicular to the plane of the skin around the skin. After cooling, the burrs will shrink and wrap around the bottom-cutting and enlarging punch, resulting in the skin sticking together.
[0077] Figure 9 The image shows the skin cut off after the bottom is cut in the example. It can be seen that there are no burrs around the skin, so the skin will not cover the bottom-cutting and hole-expanding punch, and there will be no skin sticking.
Claims
1. A method of solving the sticking skin of the automatic forging bottoming die for bearing ring, characterized in that It is done in the following steps: I. Punching Die Design: The punching die consists of an upper punching die, a lower punching die, and an outer die sleeve; the inner surface of the outer die sleeve is tapered. The upper and lower punching dies are both provided with punching punches of the same shape and size in the middle; the end face of the punching punch is provided with a transition fillet, which is a rounded chamfer, a straight line segment and an elliptical chamfer from the end face upwards; Let the end diameter of the punch be d; let the radius of the chamfer be r; let the major axis of the elliptical chamfer be r1 and the minor axis be r2; when 25mm≤d≤50mm, r=3mm~5mm, r1=3.5mm~5.5mm, r2=2mm~3.5mm; when 50mm<d≤100mm, r=5mm~10mm, r1=5.5mm~11mm, r2=3.5mm~7mm; when 100mm<d≤200mm, r=10mm~20mm, r1=5mm~22mm, r2=7mm~14mm; II. Controlling the thickness of the skin: The lower punching die and the bearing ring blank are placed inside the outer die sleeve from bottom to top. Then the upper punching die is pressed down to punch the bearing ring blank to obtain a blank with a connecting skin. The punched skin of the billet with connected skin is located in the middle of the billet, and the thickness of the punched skin is 4mm to 6mm. III. Automated forging and bottom cutting of bearing rings: The method of removing the sticky skin from the punched blank with the connecting skin in the automated forging die of bearing rings is completed by using a bottom-cutting and hole-expanding punch.
2. The method for solving the sticking skin of the automatic forging bottom cutting die for bearing ring according to claim 1, characterized in that In step one, the taper of the inner surface of the outer mold sleeve is set to γ, where γ = 2° to 6°.
3. A method of solving the sticking of the skin of the automatic forging bottom cutting die of the bearing ring according to claim 1, characterized in that In step two, the height of the bearing ring blank is H. Let the effective height of the outer mold sleeve in step one be h, then h = H + 6mm.
4. A method of solving the sticking of the skin of the automatic forging bottom cutting die of the bearing ring according to claim 1, characterized in that In step two, the maximum outer diameter of the bearing ring blank is D. Let the inner diameter of the small end of the outer mold sleeve in step one be φ, where φ = D + 2mm.
5. The method of claim 3, wherein the method further comprises Let the height of the punch in step one be h1, h1 = [H - (3mm ~ 7mm)] / 2.
6. The method of claim 1, wherein Let the taper of the punch in step one be α, where 20°≤α≤30°.
7. A method of solving the sticking skin of the automatic forging bottom cutting die for bearing ring according to claim 1, characterized in that In step one, the circle containing the round chamfer is tangent to the end face of the punch, and the ellipse containing the ellipse is tangent to the side wall of the punch; the straight line segment is located between the round chamfer and the ellipse chamfer, and is tangent to both the round chamfer and the ellipse chamfer respectively.
8. A method of solving the sticking skin of the automatic forging bottom cutting die for bearing ring according to claim 1, characterized in that The bearing ring blank mentioned in step two is a cake-shaped blank after upsetting.
9. The method of claim 3, wherein the method further comprises Let the height of the blank with skin in step two be h2, where H-1mm≤h2≤H+1mm.
10. The method of claim 1, wherein The diameter of the bottom-cutting and hole-expanding punch described in step three is the same as the diameter of the punch described in step one, and the end face of the bottom-cutting and hole-expanding punch has no chamfer.