CN108491588B - Cold space envelope forming method for thrust roller bearing ring - Google Patents
Cold space envelope forming method for thrust roller bearing ring Download PDFInfo
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- CN108491588B CN108491588B CN201810176019.XA CN201810176019A CN108491588B CN 108491588 B CN108491588 B CN 108491588B CN 201810176019 A CN201810176019 A CN 201810176019A CN 108491588 B CN108491588 B CN 108491588B
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- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F30/00—Computer-aided design [CAD]
- G06F30/10—Geometric CAD
- G06F30/17—Mechanical parametric or variational design
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D31/00—Other methods for working sheet metal, metal tubes, metal profiles
- B21D31/005—Incremental shaping or bending, e.g. stepwise moving a shaping tool along the surface of the workpiece
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D37/00—Tools as parts of machines covered by this subclass
- B21D37/10—Die sets; Pillar guides
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- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F30/00—Computer-aided design [CAD]
- G06F30/20—Design optimisation, verification or simulation
Abstract
The invention relates to a cold space enveloping forming method for constructing a thrust roller bearing ring, which comprises the following steps: s1, manufacturing a blank; s2, placing the blank on a lower die, and placing a conical roller above the blank; the cold space envelope-formed lower die cavity is matched with the back of the raceway of the ferrule forging, a conical boss matched with the inner surface of the ferrule forging is arranged in the middle of the lower die cavity, and the boss is higher than the axial height of the inner surface of the ferrule forging; the conical roller is a cone matched with a raceway of a thrust roller bearing ring forge piece, rotates around the axis of the conical roller, and revolves around the vertical axis of equipment passing through an enveloping center, and the enveloping center is positioned at the intersection point of the upper surface of the ring forge piece and the vertical axis of the equipment; s3, the lower die drives the blank to move upwards in a linear feeding mode, and the conical roller moves around the center of the wrapping net. The thrust roller bearing ring with large radial thickness, small axial height and the raceway positioned on the end surface is formed by directly cold-space enveloping of a simple rectangular ring blank, so that the production efficiency is high, the material utilization rate is high and the production cost is low.
Description
Technical Field
The invention relates to the technical field of bearing ring processing and manufacturing, in particular to a cold space enveloping forming method of a thrust roller bearing ring.
Background
The thrust roller bearing is an indispensable key basic part of moving machinery such as machine tools, automobiles, trains, ships, airplanes and the like, and the performance quality of the thrust roller bearing directly influences the performance and the service life of a main machine. The ferrule is the body of the thrust roller bearing, and the precision and the performance of the ferrule directly determine the service performance and the service life of the final thrust roller bearing product. The thrust roller bearing ring has large radial thickness and small axial height, and the raceway is positioned on the end face of the ring, so that if the thrust roller bearing ring is formed by integral die forging, the deformation resistance is large, a deformation dead zone is easy to appear, the raceway of the ring cannot be smoothly formed, and the upper die and the lower die are rigidly struck, so that the service lives of the die and equipment are seriously damaged. The ring rolling is an advanced manufacturing technology of ring parts, but is not suitable for forming the ring parts with large radial thickness and small axial height, and the complex upper and lower end surfaces of the ring parts cannot be formed by the ring rolling. Therefore, the ring rolling cannot form the thrust roller bearing ring. At present, the thrust roller bearing ring processing technology is as follows: and heating and reversely extruding the bar stock into a cylindrical piece, turning and cutting the cylindrical piece into a plurality of rectangular ring blanks, and turning the rectangular ring blanks into the ferrule part. The turning process has the advantages of multiple working procedures, low production efficiency, low material utilization rate and high production cost. Moreover, the raceway streamline of the thrust roller bearing ring is cut off, and the mechanical property of the ring is greatly weakened. Therefore, the above-described machining process cannot manufacture a high-performance thrust roller bearing ring.
The space envelope forming refers to a plastic forming method for enveloping the complex space motion track of the conical roller into the shape of the part in the relative motion process of the conical roller and the part. The cold space enveloping forming belongs to a new progressive plastic forming process, and has the advantages of high product precision, good mechanical property and structure property, high production efficiency, high material utilization rate and low production cost. More importantly, the cold space envelope forming is particularly suitable for forming parts with small axial height and complex end surface shapes. In summary, cold space envelope forming is an advanced manufacturing technology of high-performance thrust roller bearing rings. At present, no cold space envelope forming method for the thrust roller bearing ring is reported.
Disclosure of Invention
The invention aims to provide a cold space enveloping forming method of a thrust roller bearing ring.
The technical scheme adopted by the invention for solving the technical problems is as follows: a cold space envelope forming method for a thrust roller bearing ring is constructed, and comprises the following steps:
s1, manufacturing a blank, wherein the blank is a rectangular ring, the rectangular ring blank is positioned by an inner hole, and the inner diameter of the rectangular ring blank is equal to the inner diameter of the forge piece;
s2, placing the blank on a lower die, and placing a conical roller above the blank; the cold space envelope-formed lower die cavity is matched with the back of the raceway of the ferrule forging, a conical boss matched with the inner surface of the ferrule forging is arranged in the middle of the lower die cavity, and the boss is higher than the axial height of the inner surface of the ferrule forging; the conical roller is a cone matched with a raceway of a thrust roller bearing ring forge piece, rotates around the axis of the conical roller, and revolves around the vertical axis of equipment passing through an enveloping center, and the enveloping center is positioned at the intersection point of the upper surface of the ring forge piece and the vertical axis of the equipment;
s3, the lower die drives the blank to move upwards in a linear feeding mode, the conical roller moves around the enveloping center, the raceway of the thrust roller bearing ring is formed by the dynamic conical roller through multi-pass continuous space enveloping, the back of the raceway is formed by extrusion of the lower die, and when the axial height of the ring forging reaches a preset value, the lower die stops feeding.
In the above scheme, the outer diameter of the blank is determined by a deformation ratio calculation formula (1):
wherein
Is the deformation ratio of the blank, d2Is the outer diameter of the forging, d1Is the outer diameter of the blank, d0Is the inner diameter of the forging or blank.
In the scheme, the blank material is GCr15 steel, the blank is subjected to spheroidizing annealing softening treatment before being placed into a lower die, and MoS is coated on the spheroidizing annealing softened blank2And putting the lubricant into the lower die cavity.
In the scheme, the lower die is internally provided with the ejector rod.
In the scheme, any point on the conical roller moves according to the following track:
wherein, the coordinate system is positioned at the enveloping center of the conical roller, gamma is the inclination angle of the conical roller, (x, y, z) is the coordinate of any point on the conical roller, omega is the swinging angular speed of the double eccentric sleeves, and t is the cold space enveloping forming time.
In the scheme, the inclination angle of the conical roller is designed to be 0.5-1 degrees.
In the scheme, the middle part of the conical roller is provided with the conical hole with the cone angle of 90-gamma, gamma is the inclination angle of the conical roller, the diameter of the large end of the conical hole is equal to the outer diameter of the axial flash on the inner surface of the ring forging, and the bottom surface of the conical hole is higher than the upper surface of the boss in the middle part of the lower die by more than 2 mm.
The implementation of the cold space enveloping forming method of the thrust roller bearing ring has the following beneficial effects:
(1) the cold space enveloping forming method of the thrust roller bearing ring replaces the traditional cutting processing method, and the thrust roller bearing ring which has large radial thickness and small axial height and is provided with the raceway at the end surface is directly formed by the simple rectangular ring blank in the cold space enveloping forming mode, so that the production efficiency is high, the material utilization rate is high, and the production cost is low.
(2) The raceway of the thrust roller bearing ring is formed by a dynamic conical roller through multi-pass continuous space enveloping, and the surface of the raceway can form a continuous metal streamline and a compact grain structure, so that the structure and the mechanical property of the thrust roller bearing ring are obviously improved.
Drawings
The invention will be further described with reference to the accompanying drawings and examples, in which:
FIG. 1 is an axial cross-sectional view of a thrust roller bearing ring component;
FIG. 2 is an axial cross-sectional schematic view of a thrust roller bearing race forging;
FIG. 3 is an axial cross-sectional view of a rectangular ring blank;
FIG. 4 is a schematic diagram of a cold space envelope shaping of a thrust roller bearing race;
FIG. 5 is a schematic view of a three-dimensional model of a lower die for cold space envelope forming;
FIG. 6 is a schematic diagram of a three-dimensional model of a cold space envelope forming conical roller;
FIG. 7 is a schematic diagram of a three-dimensional model of a cold space envelope forming ram.
Detailed Description
For a more clear understanding of the technical features, objects and effects of the present invention, embodiments of the present invention will now be described in detail with reference to the accompanying drawings.
As shown in figure 1, the inner diameter of the thrust roller bearing ring part to be processed is 47.4mm, the outer diameter is 76mm, and the height is 9.8 mm. The envelope forming method comprises the following steps:
(1) and (5) designing a forged piece. A forging is designed by the thrust roller bearing ring part. In order to keep the metal streamline of the ferrule raceway, the surface of the raceway is added with 0.05mm grinding allowance. In order to reduce the subsequent machining allowance, the machining allowance of 0.1mm is respectively added on the other surfaces. In order to facilitate demoulding, the drawing angle of the inner surface and the outer surface of the ferrule is designed to be 3 degrees, meanwhile, the upper end surface of the outer surface of the ferrule is designed to be a horizontal flash, the upper end surface of the inner surface is designed to be an axial flash, and the thickness of the flash is 1 mm. The axial section schematic diagram of the thrust roller bearing ring forging is shown in FIG. 2.
(2) Blank 2 is designed. The blank 2 is designed into a rectangular ring, and the rectangular ring blank 2 is positioned by an inner hole, wherein the inner diameter of the inner hole is equal to the inner diameter of the forge piece by 47.2 mm. The outer diameter of the blank 2 is determined to be 65mm (the deformation rate is 0.6) by the deformation rate calculation formula (1), and the height of the blank 2 is determined to be 16.1mm according to the principle that the volumes of the blank 2 and a forging piece are unchanged. An axial cross-sectional schematic view of the rectangular ring blank 2 is shown in figure 3.
Wherein
Is the deformation ratio of the blank 2, d2Is the outer diameter of the forging, d1Is the outer diameter of the blank 2, d0Is the inner diameter of the forging or blank 2.
(3) The blank 2 is pre-treated. The blank 2 is made of GCr15 steel, and the rectangular ring blank 2 with the size required by the step (2) is obtained by rotationally cutting and blanking the pipe. The blank 2 is treated by spheroidizing annealing softening treatment, and the hardness is not higher than 190 HB.
(4) In order to improve the performance of the raceway of the thrust roller bearing ring, the raceway of the thrust roller bearing ring is formed by enveloping the dynamic conical roller 1 through multi-pass continuous space, and the back of the raceway is formed by extruding the lower die 3. The schematic diagram of the cold space envelope forming of the thrust roller bearing ring is shown in figure 4.
(5) The lower die 3 is designed. The cavity of the lower die 3 for cold space envelope forming is matched with the back of the raceway of the ferrule forging, a conical boss matched with the inner surface of the ferrule forging is arranged in the middle of the cavity of the lower die 3, and the boss is 3mm higher than the axial height of the inner surface of the ferrule forging. A schematic diagram of a three-dimensional model of the lower die 3 for cold space envelope shaping is shown in fig. 5.
(6) The conical roller 1 is designed. The cold space envelope forming conical roller 1 is a cone matched with a raceway of a thrust roller bearing ring forge piece, rotates around the axis of the cone, and revolves around the vertical axis of equipment passing through an envelope center, and the envelope center is positioned at the intersection point of the upper surface of the ring forge piece and the vertical axis of the equipment. In order to prevent the forging from warping and deforming in the cold space envelope forming process and further influence the forming precision, the inclination angle of the conical roller 1 is designed to be 0.5 degrees. In order to avoid interference between the conical roller 1 and the boss in the middle of the lower die 3, the conical hole with the cone angle of 89.5 degrees is arranged in the middle of the conical roller 1, the diameter of the large end of the conical hole is equal to the outer diameter of the axial flange on the inner surface of the ferrule forging, and the bottom surface of the conical hole is 3mm higher than the upper surface of the boss in the middle of the lower die 3. The three-dimensional model of the cold space envelope forming cone roller 1 is schematically shown in fig. 6.
(7) The movement track of the conical roller 1. In the step (6), the enveloping center of the conical roller 1 is fixed, the conical roller 1 makes complex motion around the enveloping center, and any point on the conical roller 1 moves according to the following track.
Wherein, the coordinate system is located at the envelope center of the conical roller 1, (x, y, z) is the coordinate of any point on the conical roller 1, omega is the oscillating angular velocity of the double eccentric sleeves, and t is the cold space envelope forming time.
(8) The ejector rod 4 is designed. At least 2 symmetrical ejector rods 4 are arranged in the middle of the bottom of the cavity of the lower die 3 along the circumferential direction, and the ejector rods 4 are in a fan shape and have the radial thickness of 9 mm. A schematic diagram of a three-dimensional model of the cold space envelope forming ram 4 is shown in fig. 7.
(9) MoS is coated on the blank 2 after spheroidizing annealing softening treatment2The lubricant is put into the cavity of the lower die 3 and passes through the inner surface of the cavity and the boss of the lower die 3And (4) positioning, wherein the lower die 3 drives the blank 2 to make linear feeding motion upwards, and the conical roller 1 makes track motion around the center of the wrapping according to the equation (2) in the step (7). When the axial height of the ferrule forging reaches a preset value, the lower die 3 stops feeding, and the conical roller 1 continues to move for 2 circles around the center of the wrapping so as to ensure the forming precision of the ferrule roller path. Then the lower die 3 drives the formed forge piece to return to the bottom dead center, and the 2 symmetrical ejector rods 4 move upwards to eject the ferrule forge piece.
While the present invention has been described with reference to the embodiments shown in the drawings, the present invention is not limited to the embodiments, which are illustrative and not restrictive, and it will be apparent to those skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope of the invention as defined in the appended claims.
Claims (7)
1. A cold space envelope forming method for a thrust roller bearing ring is characterized by comprising the following steps:
s1, manufacturing a blank, wherein the blank is a rectangular ring, the rectangular ring blank is positioned by an inner hole, and the inner diameter of the rectangular ring blank is equal to the inner diameter of the forge piece;
s2, placing the blank on a lower die, and placing a conical roller above the blank; the cold space envelope-formed lower die cavity is matched with the back of the raceway of the ferrule forging, a conical boss matched with the inner surface of the ferrule forging is arranged in the middle of the lower die cavity, and the boss is higher than the axial height of the inner surface of the ferrule forging; the conical roller is a cone matched with a raceway of a thrust roller bearing ring forge piece, rotates around the axis of the conical roller, and revolves around the vertical axis of equipment passing through an enveloping center, and the enveloping center is positioned at the intersection point of the upper surface of the ring forge piece and the vertical axis of the equipment;
s3, the lower die drives the blank to move upwards in a linear feeding mode, the conical roller moves around the enveloping center, the raceway of the thrust roller bearing ring is formed by the dynamic conical roller through multi-pass continuous space enveloping, the back of the raceway is formed by extrusion of the lower die, and when the axial height of the ring forging reaches a preset value, the lower die stops feeding.
2. The method of claim 1, wherein the billet outer diameter is determined by a deformation ratio calculation formula (1):
wherein
Is the deformation ratio of the blank, d2Is the outer diameter of the forging, d1Is the outer diameter of the blank, d0Is the inner diameter of the forging or blank.
3. The method for cold space envelope forming of thrust roller bearing ring according to claim 1, wherein the material of the blank is GCr15 steel, the blank is subjected to spheroidizing annealing softening treatment before being placed in the lower die, and MoS is applied to the spheroidizing annealing softened blank2And putting the lubricant into the lower die cavity.
4. The method for cold space envelope forming of a thrust roller bearing ring according to claim 1, wherein a carrier rod is provided in the lower mold.
5. The cold space envelope forming method for the thrust roller bearing ring according to claim 1, wherein any point on the conical roller moves according to the following track:
wherein, the coordinate system is positioned at the enveloping center of the conical roller, gamma is the inclination angle of the conical roller, (x, y, z) is the coordinate of any point on the conical roller, omega is the swinging angular speed of the double eccentric sleeves, and t is the cold space enveloping forming time.
6. The method for forming the cold space envelope of the thrust roller bearing ring according to claim 1, wherein the inclination angle of the conical rollers is designed to be 0.5 ° to 1 °.
7. The cold space envelope forming method for the thrust roller bearing ring according to claim 1, wherein a conical hole with a cone angle of 90-gamma is arranged in the middle of the conical roller, gamma is the inclination angle of the conical roller, the diameter of the large end of the conical hole is equal to the outer diameter of an axial flash on the inner surface of the ring forging, and the bottom surface of the conical hole is at least 2mm higher than the upper surface of a boss in the middle of the lower die.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201810176019.XA CN108491588B (en) | 2018-03-02 | 2018-03-02 | Cold space envelope forming method for thrust roller bearing ring |
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| CN201810176019.XA CN108491588B (en) | 2018-03-02 | 2018-03-02 | Cold space envelope forming method for thrust roller bearing ring |
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| CN108491588B true CN108491588B (en) | 2021-10-22 |
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| CN110479928B (en) * | 2019-08-02 | 2021-10-22 | 武汉理工大学 | Split type space envelope forming method for large-scale complex thin-wall special-shaped annular component |
| CN110918846B (en) * | 2019-11-26 | 2021-03-16 | 武汉理工大学 | Space envelope forming method of clutch outer hub component |
| CN110918844B (en) * | 2019-11-26 | 2020-12-08 | 武汉理工大学 | Thin-wall multi-ring high-rib component space envelope forming method |
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