Three-step constraint upsetting method for metal streamline regulation of special-shaped eccentric ball bearing ring
By adopting a three-step constrained upsetting method, the problem of metal flow control in the forging of irregular eccentric ball bearing rings was solved, the forming tonnage and mold requirements were reduced, the forging quality was improved, and the performance requirements of high-end irregular eccentric ball bearings were met.
Patent Information
- Application Number
- CN202410227732.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2024-02-29
- Publication Date
- 2026-02-27
- Estimated Expiration
- 2044-02-29
AI Technical Summary
In the existing forging process of irregularly shaped eccentric ball bearing rings, it is difficult to control the metal flow line, the forming resistance of the forging is large, and the requirements for forging dies are high, which leads to unstable product quality and increased production costs.
A three-step constrained upsetting method is adopted, including in-mold upsetting, local constrained upsetting, and shape-correcting upsetting. By designing specific mold combinations and deformation processes, the bending position and distribution of metal flow lines are controlled.
It reduces the tonnage required for forming, lowers the requirements for equipment and molds, improves the quality of forgings, avoids the phenomenon of metal flow lines protruding, and meets the performance requirements of high-end irregular eccentric ball bearings.
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Figure CN117900365B_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application belongs to the field of eccentrically shaped bearing ring forging. BACKGROUND
[0002] The bearing ring forging forming process generally includes upsetting-piercing-bottoming-reaming-rolling, due to the heredity of the forging process organization, the upsetting process has a decisive role on the subsequent process of the forging organization and performance. Especially for eccentrically shaped bearing ring forgings, the forming needs to precisely control the upsetting deformation. Generally, in the upsetting process, the height of the bar stock needs to be greatly reduced to ensure sufficient deformation and refine the organization. In this process, the metal flow line bends as the deformation increases, and the bending position is generally located in the middle of the bar stock. For eccentrically shaped bearing rings, the position of the metal flow line bending is quite different from the position of the channel of the forging, and there is inevitably an outcrop of the metal flow line at the channel position of the forging. This increases the risk of early failure, affects the service life of the bearing, and cannot meet the requirements of high-end eccentrically shaped bearing rings for the organization and performance of the ring forgings.
[0003] The outer diameter of the eccentrically shaped bearing is usually provided with a mounting edge, and the wall thickness of the mounting edge is usually small. If one-step upsetting forming is used, the required forming force is large, the requirements for the forging die material and service life are high, which not only affects the production cost, but also causes large deformation resistance in one-step upsetting forming, which easily causes the bar stock to be in contact with the die for a long time, reduces the temperature of the bar stock, increases the risk of cracking of the bar stock, and affects the product quality. SUMMARY
[0004] The present application solves the problem of the difficulty in controlling the metal flow line of the existing eccentrically shaped bearing ring forging, the large forming resistance of the forging, and the high requirements for the forging die, and provides a three-step constraint upsetting method for controlling the metal flow line of the eccentrically shaped bearing ring.
[0005] A three-step constraint upsetting method for controlling the metal flow line of an eccentrically shaped bearing ring, which is performed according to the following steps:
[0006] I. In-die upsetting:
[0007] The bar stock is placed in the upsetting combined die for die forging; the upsetting combined die is composed of an upsetting upper die, an upsetting lower die, and an upsetting outer sleeve, the upsetting outer sleeve is sleeved on the outside of the upsetting upper die and the upsetting lower die; during die forging, the upsetting upper die moves downward until the upsetting upper die positioning point is flush with the upper end of the upsetting outer sleeve, a predetermined deformation amount is reached, and a bar stock with an outer diameter and a boss is obtained;
[0008] The height of the bar stock is H, the diameter of the bar stock is d, the inner diameter of the upsetting lower die is d1, the height of the upsetting lower die is h1, and the height of the bar stock with an outer diameter and a boss is H1;
[0009] II. Partially-restrained upsetting:
[0010] The lower part of the outer diameter with boss blank is placed in the partially-restrained upsetting lower die to hammer upsetting, the upper part height of the outer diameter with boss blank is controlled by the pad during the upsetting process, and the blank after partially-restrained upsetting is obtained;
[0011] The inner diameter of the partially-restrained upsetting lower die is d2, the height of the partially-restrained upsetting lower die is h2, the height of the blank after partially-restrained upsetting is H2, d1+3mm≤d2≤d1+10mm, and h2≤h1-10mm;
[0012] III. Shaping upsetting:
[0013] The blank after partially-restrained upsetting is placed in the shaping upsetting combined die to perform shaping; the shaping upsetting combined die is composed of a shaping upsetting upper die, a shaping upsetting lower die and a shaping upsetting outer sleeve, the shaping upsetting outer sleeve is sleeved outside the shaping upsetting upper die and the shaping upsetting lower die; during the shaping process, the shaping upsetting upper die moves downward until the shaping upsetting upper die positioning point is flush with the upper end of the shaping upsetting outer sleeve, the thickness of the blank boss is compressed to L, the predetermined deformation is reached, and the blank after shaping upsetting is obtained;
[0014] The height of the shaping upsetting lower die is h3, the inner diameter of the shaping upsetting lower die is d3, the height of the blank after shaping upsetting is H3, H2-10mm≤H3≤H2, h2-5mm≤h3≤h2+5mm, and d2+5mm≤d3≤d2+20mm;
[0015] IV. Punching-bottoming-enlarging-hubbing:
[0016] The blank after shaping upsetting is sequentially subjected to punching, bottoming, enlarging and hubbing to obtain the special-shaped eccentric ball bearing ring forging;
[0017] The height of the channel center position of the special-shaped eccentric ball bearing ring forging is l, (h3+0.2L)≤l≤(h3+0.8L).
[0018] The beneficial effects of the present application are:
[0019] The present application divides the upsetting process of the special-shaped eccentric ball bearing into three steps through the design of the upsetting die, the in-die upsetting realizes the pre-bending deformation of the metal flow line at a specific place, the partially-restrained upsetting realizes the deformation of the blank only at a set height, the metal flow line is bent at a fixed height, the shaping upsetting reduces the height of the outer diameter boss, and the blank shape required for the subsequent process (punching-bottoming-enlarging-hubbing) is ensured.
[0020] Firstly, the three-step restrained upsetting forming reduces the required tonnage (by more than 50%) and reduces the requirements of the equipment and die for the special-shaped eccentric ball bearing forging forming.
[0021] Secondly, by local constraint upsetting, the metal flow is precisely regulated, the metal flow line of the eccentric bearing forging channel position is distributed along the shape, the channel metal head is avoided, and the forging quality is improved.
[0022] The application is used for a three-step constraint upsetting method for regulating the metal flow line of a special-shaped eccentric ball bearing ring. BRIEF DESCRIPTION OF DRAWINGS
[0023] Figure 1 The figure is a schematic diagram of the forging process of the existing special-shaped eccentric ball bearing ring in the comparative experiment;
[0024] Figure 2 The figure is a schematic diagram of the process of steps one to three of the application;
[0025] Figure 3 The figure is a schematic diagram of the structure of the upsetting combined die in step one of the application;
[0026] Figure 4 The figure is a schematic diagram of the structure of the local constraint upsetting lower die in step two of the application;
[0027] Figure 5 The figure is a schematic diagram of the structure of the shape correcting upsetting combined die in step three of the application;
[0028] Figure 6 The figure is a metal flow line evolution diagram of steps one to three of the embodiment;
[0029] Figure 7 The figure is a comparison diagram of the forming force and the metal flow line in the embodiment one and the comparative experiment. DETAILED DESCRIPTION
[0030] The technical scheme of the application is not limited to the following specific embodiments, and any combination of the specific embodiments is also included.
[0031] Specific embodiment one, in combination with Figures 2 to 5 Specific description: the three-step constraint upsetting method for regulating the metal flow line of a special-shaped eccentric ball bearing ring is performed according to the following steps:
[0032] I. In-die upsetting:
[0033] The bar is placed in the upsetting combined die for die forging; the upsetting combined die is composed of an upsetting upper die, an upsetting lower die and an upsetting outer sleeve, and the upsetting outer sleeve is sleeved on the outside of the upsetting upper die and the upsetting lower die; during the die forging process, the upsetting upper die moves downward until the upsetting upper die positioning point is flush with the upper end of the upsetting outer sleeve, a predetermined deformation amount is reached, and a blank with a boss on the outer diameter is obtained;
[0034] The height of the bar is H, the diameter is d, the inner diameter of the upsetting lower die is d1, the height of the upsetting lower die is h1, and the height of the outer diameter with a boss is H1;
[0035] II. Local constraint upsetting:
[0036] The lower part of the boss of the outer diameter with a boss is placed in the local constraint upsetting lower die to hammer up, and the upper part of the outer diameter with a boss is controlled by the cushion block during the upsetting process, so as to obtain the blank after local constraint upsetting.
[0037] The inner diameter of the local constraint upsetting lower die is d2, the height of the local constraint upsetting lower die is h2, and the height of the blank after local constraint upsetting is H2, d1+3mm≤d2≤d1+10mm, and h2≤h1-10mm.
[0038] III. Correcting upsetting:
[0039] The blank after local constraint upsetting is placed in the correcting upsetting combined die to correct; the correcting upsetting combined die is composed of a correcting upsetting upper die, a correcting upsetting lower die and a correcting upsetting outer sleeve, and the correcting upsetting outer sleeve is sleeved outside the correcting upsetting upper die and the correcting upsetting lower die; during the correcting process, the correcting upsetting upper die moves downward until the correcting upsetting upper die positioning point is flush with the upper end of the correcting upsetting outer sleeve, the thickness of the blank boss is compressed to L, the predetermined deformation is reached, and the blank after correcting upsetting is obtained.
[0040] The height of the correcting upsetting lower die is h3, the inner diameter of the correcting upsetting lower die is d3, and the height of the blank after correcting upsetting is H3, H2-10mm≤H3≤H2, h2-5mm≤h3≤h2+5mm, d2+5mm≤d3≤d2+20mm.
[0041] IV. Punching-bottom cutting-boring-rolling:
[0042] The blank after correcting upsetting is sequentially punched, bottom cut, bored and rolled to obtain the special-shaped eccentric ball bearing ring forging.
[0043] The height of the center of the groove of the special-shaped eccentric ball bearing ring forging is l, (h3+0.2L)≤l≤(h3+0.8L).
[0044] The second step of the embodiment restricts the diameter of the blank by the inner diameter of the local constraint upsetting lower die, so that the height of the blank above the local constraint upsetting lower die is reduced during the upsetting process, and the metal flow line only bends in this part, i.e. local bending.
[0045] The beneficial effects of the embodiment are:
[0046] The present embodiment divides the upsetting process of the special-shaped eccentric ball bearing into three steps by designing the upsetting die, realizes the pre-bending deformation of the metal flow line in a specific place by in-die upsetting, realizes the deformation of the blank only at a set height by local constraint upsetting, realizes the bending of the metal flow line at a fixed height, and reduces the height of the outer diameter boss by shape correcting upsetting, thereby ensuring the required blank shape in the subsequent processes (punching, bottom cutting, hole expanding, and pad rolling).
[0047] Firstly, the three-step constraint upsetting forming reduces the required tonnage (by more than 50%) and reduces the requirements of the equipment and die for the special-shaped eccentric ball bearing forging forming.
[0048] Secondly, the precise regulation of the metal flow by local constraint upsetting realizes the random distribution of the metal flow line at the channel position of the eccentric ball bearing forging, avoids the metal exposure at the channel, and improves the forging quality.
[0049] Specific embodiment two: different from the specific embodiment one, the local constraint upsetting lower die inner diameter is provided with a draft angle a in step two, 3°≤a≤7°. The others are the same as the specific embodiment one.
[0050] Specific embodiment three: different from the specific embodiment one or two, the pad height is the same as the blank height H2 after the local constraint upsetting in step two. The others are the same as the specific embodiment one or two.
[0051] Specific embodiment four: different from the specific embodiment one to three, H1=(0.6-0.85)H in step one. The others are the same as the specific embodiment one to three.
[0052] Specific embodiment five: different from the specific embodiment one to four, h1=(0.3-0.5)H in step one. The others are the same as the specific embodiment one to four.
[0053] Specific embodiment six: different from the specific embodiment one to five, d+3mm≤d1≤d+10mm in step one. The others are the same as the specific embodiment one to five.
[0054] Specific embodiment seven: different from the specific embodiment one to six, H1-30mm≤H2≤H1-10mm in step two. The others are the same as the specific embodiment one to six.
[0055] Specific embodiment eight: different from the specific embodiment one to seven, the punch used for punching in step four is a straight punch, and the punch diameter is (0.2-0.4)d3. The others are the same as the specific embodiment one to seven.
[0056] Specific embodiment nine: the difference between this embodiment and one of the specific embodiments one to eight is that the punch used in the step four is a V-shaped punch, and the punch angle is 25°-40°. The others are the same as the specific embodiments one to eight.
[0057] Specific embodiment ten: the difference between this embodiment and one of the specific embodiments one to nine is that the blank width H4 after the step four is set to be expanded, and the width H5 of the forged piece after the rolling expansion is H5-3mm≤H4≤H5. The others are the same as the specific embodiments one to nine.
[0058] The beneficial effects of the present application are verified by the following examples:
[0059] Example one, combined with Figures 2 to 5 Specific description:
[0060] A three-step constraint upsetting method for metal streamline regulation of a special-shaped eccentric spherical bearing ring, which is carried out according to the following steps:
[0061] I. Upsetting in the mold:
[0062] The bar is placed in the upsetting combined die to perform die forging; the upsetting combined die is composed of an upsetting upper die, an upsetting lower die and an upsetting outer sleeve, and the upsetting outer sleeve is sleeved outside the upsetting upper die and the upsetting lower die; during the die forging process, the upsetting upper die moves downward until the upsetting upper die positioning point is flush with the upper end of the upsetting outer sleeve, a predetermined deformation amount is reached, and a blank with a boss on the outer diameter is obtained;
[0063] The height of the bar is H, H=165mm, the diameter is d, d=166mm, the inner diameter of the upsetting lower die is d1, d1=176mm, the height of the upsetting lower die is h1, h1=70mm, and the height of the blank with the boss on the outer diameter is H1, H1=122mm;
[0064] II. Local constraint upsetting:
[0065] The boss lower part of the blank with the boss on the outer diameter is placed in the local constraint upsetting lower die to perform hammer upsetting, and the height of the upper part of the blank with the boss on the outer diameter is controlled by using a pad during the upsetting process, so as to obtain the blank after the local constraint upsetting;
[0066] The inner diameter of the local constraint upsetting lower die is d2, d2=184mm, the height of the local constraint upsetting lower die is h2, h2=55mm, the height of the blank after the local constraint upsetting is H2, H2=106mm, d1+3mm≤d2≤d1+10mm, and h2≤h1-10mm;
[0067] III. Shaping upsetting:
[0068] The partially constrained upset blank is placed in a shape correcting and upsetting combined die for shape correction; the shape correcting and upsetting combined die is composed of a shape correcting and upsetting upper die, a shape correcting and upsetting lower die and a shape correcting and upsetting outer sleeve, the shape correcting and upsetting outer sleeve is sleeved outside the shape correcting and upsetting upper die and the shape correcting and upsetting lower die; during the shape correction, the shape correcting and upsetting upper die moves downward until the shape correcting and upsetting upper die positioning point is flush with the upper end of the shape correcting and upsetting outer sleeve, the thickness of the blank boss is compressed to L, L = 21 mm, the predetermined deformation amount is reached, and the blank after shape correcting and upsetting is obtained;
[0069] The height of the shape correcting and upsetting lower die is h3, h3 = 51 mm, the inner diameter of the shape correcting and upsetting lower die is d3, d3 = 200 mm, the height of the blank after shape correcting and upsetting is H3, H3 = 98 mm, H2-10 mm≤H3≤H2, h2-5 mm≤h3≤h2+5 mm, d2+5 mm≤d3≤d2+20 mm;
[0070] Four, punching, bottom cutting, hole expanding and hole expanding:
[0071] The blank after shape correcting and upsetting is sequentially punched, bottom cut, hole expanded and hole expanded to obtain a special-shaped eccentric ball bearing ring forging;
[0072] The height of the center of the channel of the special-shaped eccentric ball bearing ring forging is l, l = 56.5 mm, (h3+0.2L)≤l≤(h3+0.8L).
[0073] The partially constrained upsetting lower die inner diameter in step two is provided with a draft angle α, α = 5°.
[0074] The height of the pad in step two is the same as the height H2 of the blank after partially constrained upsetting.
[0075] The punch used in step four is a straight punch, and the diameter of the punch is 0.25×d 3＝ 50 mm.
[0076] The punch used in step four is a V-shaped punch, and the angle of the punch is 30°.
[0077] In step four, the height of the blank after hole expanding is H4, H4 = 87.5 mm, the height of the forging after hole expanding is H5, H5 = 88 mm, H5-3 mm≤H4≤H5.
[0078] The rod in step one of the embodiment is BG801 steel.
[0079] Comparative experiment, combined Figure 1Specific details: This comparative experiment differs from Example 1 in that it employs a one-step upsetting process, eliminating steps one and two. The bar stock is directly placed in the shaping and upsetting die combination for shaping. During the shaping process, the upper die moves downward until the thickness of the billet boss is compressed to L, where L = 21 mm, resulting in a one-step upsetting billet. This billet is then subjected to punching, bottom cutting, hole enlargement, and rolling to obtain the irregularly shaped eccentric ball bearing ring forging. Everything else is the same as in Example 1.
[0080] Figure 6 The diagram shows the metal flow line evolution in steps one through three of Example 1. As can be seen from the diagram, after three-step upsetting, the metal flow during each upsetting deformation process is precisely controllable under the constraint of the die. First, in-die upsetting achieves bending of the metal flow line at a specific height; second, by constraining the lower half of the billet, local metal flow line control is achieved for the irregularly shaped eccentric ball bearing ring; finally, the limiting effect of the shaping upsetting die ensures that the upset billet meets the dimensions required for subsequent processing.
[0081] Figure 7 This is a comparison diagram of forming force and metal flow lines in Example 1 and the comparative experiment. Because the forging material is BG801 steel, which is very difficult to deform and has high deformation resistance, the diagram shows that the forming force required for the original one-step upsetting process in the comparative experiment was approximately 3600 tons. Using the three-step upsetting method in Example 1, the maximum forming force (1200 tons, 1100 tons, and 1400 tons respectively) was reduced by about 60%, significantly reducing the equipment requirements for forming irregularly shaped eccentric ball bearing rings. Furthermore, using the original process in the comparative experiment, the metal flow lines bent in the middle of the forging after upsetting, causing the metal flow lines to protrude at the groove. Using the three-step upsetting method in Example 1, the metal flow lines bent at specific groove locations after upsetting, ultimately resulting in bent metal flow lines at the groove of the forging, with the groove metal flow lines distributed according to the shape and no protrusion phenomenon.
Claims
1. A three-step constrained-upsetting method for profiled eccentric ball bearing ring metal flow line regulation, characterized in that It is carried out according to the following steps: I. Upsetting in mold: Put the bar material in the upsetting combined die to carry out die forging; the upsetting combined die is composed of an upsetting upper die, an upsetting lower die and an upsetting outer sleeve, the upsetting outer sleeve is sleeved on the outside of the upsetting upper die and the upsetting lower die; during die forging, the upsetting upper die moves downward until the positioning point of the upsetting upper die is flush with the upper end of the upsetting outer sleeve, a predetermined deformation amount is reached, and a blank with a boss on the outer diameter is obtained; The height of the bar material is H, the diameter is d, the inner diameter of the upsetting lower die is d1, the height of the upsetting lower die is h1, and the height of the blank with the boss on the outer diameter is H1; H1=(0.6~0.85)H; II. Partially-restrained upsetting: Put the boss lower part of the blank with the boss on the outer diameter in the partially-restrained upsetting lower die to carry out hammering and upsetting, use a pad to control the height of the upper part of the blank with the boss on the outer diameter during the upsetting process, and obtain the blank after partially-restrained upsetting; The inner diameter of the partially-restrained upsetting lower die is d2, the height of the partially-restrained upsetting lower die is h2, the height of the blank after partially-restrained upsetting is H2, d1+3mm≤d2≤d1+10mm, h2≤h1-10mm; H1-30mm≤H2≤H1-10mm; III. Correcting upsetting: Put the blank after partially-restrained upsetting in the correcting upsetting combined die to carry out correcting; the correcting upsetting combined die is composed of a correcting upsetting upper die, a correcting upsetting lower die and a correcting upsetting outer sleeve, the correcting upsetting outer sleeve is sleeved on the outside of the correcting upsetting upper die and the correcting upsetting lower die; during correcting, the correcting upsetting upper die moves downward until the positioning point of the correcting upsetting upper die is flush with the upper end of the correcting upsetting outer sleeve, the thickness of the boss of the blank is compressed to L, a predetermined deformation amount is reached, and the blank after correcting upsetting is obtained; The height of the correcting upsetting lower die is h3, the inner diameter of the correcting upsetting lower die is d3, the height of the blank after correcting upsetting is H3, H2-10mm≤H3≤H2, h2-5mm≤h3≤h2+5mm, d2+5mm≤d3≤d2+20mm; IV. Punching, bottom cutting, hole expanding and upsetting: Carry out punching, bottom cutting, hole expanding and upsetting on the blank after correcting upsetting in sequence, and obtain a special eccentric ball bearing ring forging; The height of the center of the channel of the special eccentric ball bearing ring forging is l, (h3+0.2L)≤l≤(h3+0.8L).
2. A three-step constrained-upsetting method for profiled eccentric ball bearing ring metal flow line regulation according to claim 1, characterized in that The inner diameter of the partially-restrained upsetting lower die in step II is provided with a draft angle α, 3°≤α≤7°.
3. A three-step constrained-upsetting method for profiled eccentric ball bearing ring metal flow line regulation according to claim 1, characterized in that The height of the pad in step II is the same as the height H2 of the blank after partially-restrained upsetting.
4. A three-step constrained-upsetting method for profiled eccentric ball bearing ring metal flow line regulation according to claim 1, characterized in that In step I, h1=(0.3~0.5)H.
5. A three-step constrained-upsetting method for profiled eccentric ball bearing ring metal flow line regulation according to claim 1, characterized in that In step I, d+3mm≤d1≤d+10mm.
6. A three-step constrained-upsetting method for profiled eccentric ball bearing ring metal flow line control according to claim 1, characterized in that In step IV, the punch used for punching is a straight punch, and the diameter of the punch is (0.2~0.4)d3.
7. A three-step constrained-upsetting method for profiled eccentric ball bearing ring metal flow line control according to claim 1, characterized in that In step IV, the punch used for hole expanding is a V-shaped punch, and the angle of the punch is 25°~40°.
8. A three-step constrained-upsetting method for profiled eccentric ball bearing ring metal flow line regulation according to claim 1, characterized in that In step IV, the height of the blank after hole expanding is H4, and the height of the forging after upsetting is H5, H5-3mm≤H4≤H5.