A wedge cross-rolling forming device and forming method for ball parts

Abstract

The present invention relates to the technical field of metal plastic forming process, and provides a wedge cross-rolling forming device and forming method for ball parts. The forming method includes wedging, forming, finishing and cutting. In the wedging stage, the wedge tip of the mold wedges into the bar material, driving the bar material to rotate; in the forming stage, the bar material rolls and deforms into a sphere under the action of the mold forming hole type, and a connecting neck is formed between adjacent spherical parts; in the finishing stage, the spherical parts obtain a more accurate target size under the action of the finishing section cavity, eliminating surface defects that may be generated in the wedging and forming stages; in the cutting stage, the cutting ridges set at the end of the mold cavity cut off the connecting neck to form a complete set of spherical parts, and the mold continues to rotate to enter the next forming cycle. The ball parts formed by the method of the present invention have high precision and good quality, and have the advantages of high production efficiency and high material utilization. They can be used for mass production of precision ball parts and have broad application prospects.

Description

Technical Field

[0001] The invention relates to the technical field of metal plastic forming technology, and in particular to a wedge cross-rolling forming device and a forming method for ball parts. Background Art

[0002] Ball parts are important and indispensable products for applications in mining, building materials, coal and other industrial sectors, as well as bearing manufacturing. The current production methods are mainly concentrated on casting, forging, cold heading and oblique rolling. Traditional casting, forging, cold heading and other processes have disadvantages such as low production efficiency, poor working environment and high equipment cost. The production efficiency of oblique rolling ball parts is high, but the dimensional accuracy of the formed ball parts is not high, and surface defects and loose core are prone to occur, which cannot meet the requirements of high-performance precision ball parts. Therefore, it is necessary to develop new ball parts forming methods for mass production of high-performance and high-precision ball parts to meet the needs of industries such as bearing steel balls.

[0003] As an efficient metal plastic forming process, wedge cross rolling is recognized as an important part of today's advanced manufacturing technology. It has been widely adopted by the market due to its many advantages such as high production efficiency and high material utilization.

[0004] There is no prior art that uses wedge cross-rolling technology to produce multiple ball parts by one wedge cross-rolling. Summary of the invention

[0005] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a wedge cross-rolling forming device and a forming method for ball parts, which improves the surface accuracy and core quality of ball parts and has the advantages of high material utilization, high production efficiency and high product quality.

[0006] The present invention adopts the following technical solution:

[0007] On the one hand, the present invention provides a wedge cross-rolling forming device for ball parts, comprising an upper roller, a lower roller and a guide plate;

[0008] The upper roller and the lower roller are provided with an upper die and a lower die respectively; the upper die and the lower die both include a plurality of semi-forming holes arranged side by side, and the adjacent semi-forming holes are separated from each other by convex ridges; the upper die and the lower die are arranged opposite to each other, and two corresponding semi-forming holes arranged on the upper die and the lower die form a complete forming hole; the plurality of forming holes are used to obtain a plurality of ball parts by wedge-rolling a metal bar at one time;

[0009] The guide plate is arranged between the upper die and the lower die, and is used to fix the position of the metal bar during the wedge cross rolling process.

[0010] As any possible implementation described above, an implementation is further provided, in which among the semi-formed pass profiles of multiple passes, the semi-formed pass profile of the middle pass has the longest length, and the length decreases successively toward both sides.

[0011] According to any possible implementation described above, there is further provided an implementation, wherein the upper mold and the lower mold both include a wedging section, a forming section, and a finishing section connected in sequence;

[0012] The wedging section is used for the mold wedge tip to wedge into the metal bar, the ridge of the forming section gradually rises to a set height, the ridge of the finishing section is maintained at the set height, the rear section of the finishing section is provided with a cutting section, and the cutting section is provided with a cutting ridge for cutting off the connecting necks between adjacent ball parts.

[0013] Any possible implementation described above further provides an implementation, wherein the length range of the cut ridge is:

[0014]

[0015] Where l is the length of the cut ridge and L is the total length of the finishing section.

[0016] Any possible implementation described above further provides an implementation, wherein the height range of the convex ridges of the finishing section is set as follows:

[0017] 0.9R <H<R;

[0018] Wherein, H is the height of the ridge of the finishing section, and R is the diameter of the formed spherical part.

[0019] Any possible implementation as described above further provides an implementation, wherein two guide plates are symmetrically arranged on both sides of the metal bar; a plurality of support columns and separation grooves spaced apart from each other are arranged on opposite sides of the two guide plates, the support columns are used to limit the position of the metal bar and / or ball parts, and the position of the support columns corresponds to the recessed portion of the semi-formed hole; the position of the separation groove corresponds to the position of the convex ridge of the semi-formed hole, so as to prevent the convex ridge from interfering with the guide plate.

[0020] Any possible implementation as described above further provides an implementation, in which during the forming process of the ball parts, the semi-formed hole types corresponding to the upper die and the lower die are always symmetrical about the center axis of the metal bar.

[0021] According to any possible implementation described above, there is further provided an implementation, wherein the axes of the upper die, the lower die and the metal bar are located in the same plane, and the distance between the axes of the upper die and the lower die is:

[0022] d=D+d0;

[0023] Where d is the distance between the upper and lower mold axes, D is the diameter of the upper and lower molds, and d0 is the diameter of the metal bar.

[0024] Any possible implementation as described above further provides an implementation in which the cutting ridge of the upper mold and the cutting ridge of the lower mold are tangent to each other.

[0025] Any possible implementation as described above further provides an implementation, wherein the upper mold and the lower mold are arranged up and down, or arranged horizontally at the same height, and are respectively suitable for a vertical cross wedge rolling mill and a horizontal cross wedge rolling mill.

[0026] On the other hand, the present invention also provides a wedge cross-rolling forming method for ball parts, using the wedge cross-rolling forming device for ball parts according to any one of claims 1 to 8, the forming method comprising:

[0027] S1, wedging stage: the metal bar is fed into the space defined by two guide plates between the upper die and the lower die, the wedge tips of the wedging sections of the upper die and the lower die correspond to each other, the upper die and the lower die rotate at the same speed and in the same direction, the two wedge tips wedge into the middle of the metal bar, driving the metal bar to rotate and roll;

[0028] S2, forming stage: the convex ridges of the semi-forming holes of the upper die and the lower die extrude the metal bar. As the convex ridges of the forming section of the die rise, the metal bar is gradually formed into multiple ball parts with connecting necks by multiple forming holes during rotation and rolling;

[0029] S3, finishing stage: multiple ball parts with connecting necks are rolled and finished in the forming hole of the finishing section of the mold to eliminate forming defects, improve roundness, and enhance the dimensional accuracy of the ball parts;

[0030] S4, cutting stage: in the cutting section after the finishing section, the convex ridges are cut off to cut off the connecting necks between the ball parts to form a group of ball parts separated from each other; the upper mold and the lower mold return to the initial position at the same time to enter the next forming cycle.

[0031] Any possible implementation as described above further provides an implementation, wherein the forming method is used for hot forming, warm forming, and cold forming processes, and the forming method is used for the preparation of φ1-φ100mm ball parts.

[0032] The beneficial effects of the present invention are as follows: the present invention can be used to form multiple ball parts of the same size at one time by arranging multiple ball parts forming hole patterns in parallel on a pair of wedge cross-rolling dies, and two guide plates that are relatively arranged to limit metal bars, thereby greatly improving production efficiency, greatly reducing mold material consumption, simplifying the process, and significantly saving production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 Shown is a schematic diagram of the stages of a wedge cross-rolling forming method for ball parts according to an embodiment of the present invention.

[0034] Figure 2 Shown is a schematic diagram of the arrangement of the upper mold and the lower mold in the embodiment.

[0035] Figure 3 Shown is a schematic diagram of the upper mold (lower mold) in the embodiment.

[0036] Figure 4 Shown is a schematic diagram of the guide plate arrangement in the embodiment.

[0037] Figure 5 Shown is a schematic diagram of the guide plate structure in the embodiment.

[0038] Figure 6 Shown is a schematic diagram of a ball part with a connecting neck in an embodiment.

[0039] In the figure: 1-upper die; 2-guide plate; 3-metal bar; 4-lower die; 5-cutting ridge; 6-semi-forming hole; 7-separation groove; 8-support column. DETAILED DESCRIPTION

[0040] The specific embodiments of the present invention will be described in detail below in conjunction with specific drawings. It should be noted that the technical features or combinations of technical features described in the following embodiments should not be considered isolated, and they can be combined with each other to achieve better technical effects. In the drawings of the following embodiments, the same reference numerals appearing in each drawing represent the same features or components, which can be applied to different embodiments.

[0041] like Figure 2 As shown, an embodiment of the present invention is a wedge-cross rolling forming device for ball parts, comprising an upper rolling roller, a lower rolling roller and a guide plate 2; an upper mold 1 and a lower mold 4 are respectively arranged on the upper rolling roller and the lower rolling roller; the upper mold 1 and the lower mold 4 both include a plurality of semi-forming hole profiles 6 arranged side by side, among which the semi-forming hole profiles 6 of the middle pass are the longest, and decrease successively toward both sides; adjacent semi-forming hole profiles 6 are separated from each other by convex ridges; the upper mold 1 and the lower mold 4 are arranged opposite to each other, and the two corresponding semi-forming hole profiles 6 arranged on the upper mold 1 and the lower mold 4 form a complete forming hole profile; a plurality of the forming hole profiles are used for obtaining a plurality of ball parts by wedge-cross rolling the metal bar 3 at one time; the guide plate 2 is arranged between the upper mold 1 and the lower mold 4, and is used to fix the position of the metal bar 3 during the wedge-cross rolling process.

[0042] In a specific embodiment, Figure 3As shown, the upper die 1 and the lower die 4 both include a wedging section, a forming section, and a finishing section; the wedging section is used for the die tip to wedge into the metal rod 3, the convex rib of the forming section gradually rises to a set height, the convex rib of the finishing section remains at the set height, a cutting section is provided at the rear section of the finishing section, and a cutting convex rib 5 is provided in the cutting section for cutting the connecting neck between adjacent spherical parts.

[0043] In a specific embodiment, the length range of the cutting convex rib 5 is: In the formula, l is the length of the cutting convex rib, and L is the total length of the finishing section.

[0044] In a specific embodiment, the set height range of the convex rib of the finishing section is: 0.9R < H < R; in the formula, H is the set height of the convex rib of the finishing section, and R is the diameter of the formed spherical part.

[0045] In a specific embodiment, N semi-circular hole patterns 6 are arranged in parallel on the surfaces of the upper die 1 and the lower die 4. During a single forming cycle, the number of formed spherical parts is equal to the number N of the semi-circular hole patterns 6, and the diameter of the semi-circular hole pattern 6 is equal to the target diameter of the spherical part.

[0046] In a specific embodiment, as Figure 4 , Figure 5 shown, to prevent the metal rod 3 from moving and ensure the forming effect, two guide plates 2 are symmetrically arranged on both sides of the metal rod 3. The gap between the guide plates 2 is slightly larger than the diameter of the metal rod 3 to limit the swinging displacement of the metal rod 3 in the direction perpendicular to the axis; a number of support columns 8 and separation grooves 7 are arranged at intervals on the opposite sides of the two guide plates 2. The support columns 8 are used to limit the position of the metal rod 3 and / or the spherical part, and the position of the support columns 8 corresponds to the concave part of the semi-formed hole pattern 6; the position of the separation groove 7 corresponds to the convex rib position of the semi-formed hole pattern 6 to prevent interference between the convex rib and the guide plate 2 during the movement of the die.

[0047] In a specific embodiment, during the forming process of the spherical part, the corresponding semi-formed hole patterns 6 of the upper die 1 and the lower die 4 are always centrosymmetric about the axis of the metal rod 3.

[0048] In a specific embodiment, the axes of the upper die 1, the lower die 4, and the metal rod 3 are located in the same plane, and the axial distance between the upper die 1 and the lower die 4 is: d = D + d0; in the formula, d is the axial distance between the upper die 1 and the lower die 4, D is the diameter of the upper die 1 and the lower die 4, and d0 is the diameter of the metal rod 3.

[0049] In a specific embodiment, the cutting convex ribs 5 of the upper die 1 and the cutting convex ribs 5 of the lower die 4 are tangent to each other to ensure cutting the connecting neck between the spherical parts.

[0050] In a specific embodiment, the upper mold 1 and the lower mold 4 are arranged up and down, or arranged horizontally at the same height, and are respectively suitable for a vertical cross-wedge rolling mill and a horizontal cross-wedge rolling mill.

[0051] like Figure 1 As shown, a wedge cross-rolling forming method for ball parts according to an embodiment of the present invention uses the above-mentioned wedge cross-rolling forming device for ball parts, and the forming method includes:

[0052] S1, wedging stage: the metal bar 3 is fed into the space defined by the two guide plates 2 between the upper die 1 and the lower die 4, the wedge tips of the wedging sections of the upper die 1 and the lower die 4 correspond to each other, the upper die 1 and the lower die 4 rotate at the same speed and in the same direction, the two wedge tips wedge into the middle of the metal bar 3, driving the metal bar 3 to rotate and roll, and the rotation direction of the metal bar 3 is opposite to that of the die;

[0053] S2, forming stage: the ridges of the semi-forming holes 6 of the upper die 1 and the lower die 4 squeeze the metal bar 3. As the ridges of the forming section of the die rise, the metal bar 3 is gradually formed into multiple ball parts with connecting necks by multiple forming holes during rotation and rolling, such as Figure 6 As shown;

[0054] S3, finishing stage: multiple ball parts with connecting necks are rolled and finished in the forming hole of the finishing section of the mold to eliminate forming defects, improve roundness, and enhance the dimensional accuracy of the ball parts;

[0055] S4, cutting stage: in the cutting section after the finishing section, the convex ridge 5 is cut off to cut off the connecting necks between the ball parts to form a group of ball parts separated from each other; the upper mold 1 and the lower mold 4 return to the initial position at the same time and enter the next forming cycle.

[0056] In a specific embodiment, the forming method is used for hot forming, warm forming, and cold forming processes, and the forming method is used for the preparation of φ1-φ100mm ball parts.

[0057] The ball parts formed by the method of the present invention have high precision and good quality, and have the advantages of high production efficiency and high material utilization rate. The method can be used for batch production of precision ball parts and has broad application prospects.

[0058] Although several embodiments of the present invention have been given herein, those skilled in the art should understand that the embodiments of the present invention may be modified without departing from the spirit of the present invention. The above embodiments are merely exemplary and should not be used as a limitation on the scope of the present invention.

Claims

1. A wedge cross-rolling forming device for ball parts, characterized in that: The forming device comprises an upper roller, a lower roller and a guide plate; The upper roller and the lower roller are provided with an upper die and a lower die respectively; the upper die and the lower die both include a plurality of semi-forming holes arranged side by side, and the adjacent semi-forming holes are separated from each other by convex ridges; the upper die and the lower die are arranged opposite to each other, and two corresponding semi-forming holes arranged on the upper die and the lower die form a complete forming hole; the plurality of forming holes are used to obtain a plurality of ball parts by wedge-rolling a metal bar at one time; The guide plate is arranged between the upper die and the lower die, and is used to fix the position of the metal bar during the wedge cross rolling process; The upper mold and the lower mold each include a wedging section, a forming section, and a finishing section connected in sequence; The wedging section is used for the tip of the die wedge to wedge into the metal bar, the ridge of the forming section gradually rises to a set height, the ridge of the finishing section is maintained at the set height, the rear section of the finishing section is provided with a cutting section, and the cutting section is provided with a cutting ridge for cutting off the connection necks between adjacent ball parts; The length range of the cutting ridge is: In the formula, l is the length of the cut ridge, and L is the total length of the finishing section; The height setting range of the convex edge of the finishing section is: 0.9R <H<R; In the formula, H is the height of the convex edge of the finishing section, and R is the diameter of the formed ball part; Two guide plates are symmetrically arranged on both sides of the metal bar; a plurality of support columns and separation grooves are arranged at intervals on the opposite sides of the two guide plates, the support columns are used to limit the position of the metal bar and / or ball parts, and the position of the support columns corresponds to the recessed portion of the semi-formed hole; the position of the separation groove corresponds to the position of the convex ridge of the semi-formed hole, so as to prevent the convex ridge from interfering with the guide plate.

2. The wedge cross-rolling forming device for ball parts according to claim 1, characterized in that: During the forming process of the ball parts, the semi-formed hole profiles corresponding to the upper die and the lower die are always symmetrical about the center axis of the metal bar.

3. The wedge cross-rolling forming device for ball parts according to claim 1, characterized in that: The axes of the upper die, the lower die and the metal bar are located in the same plane, and the distance between the axes of the upper die and the lower die is: d=D+d0; Where d is the distance between the upper and lower mold axes, D is the diameter of the upper and lower molds, and d0 is the diameter of the metal bar.

4. The wedge cross-rolling forming device for ball parts according to claim 1, characterized in that: The cutting ridge of the upper die and the cutting ridge of the lower die are tangent to each other.

5. The wedge cross-rolling forming device for ball parts according to claim 1, characterized in that: The upper die and the lower die are arranged up and down, or arranged horizontally at the same height, and are respectively suitable for a vertical cross wedge rolling mill and a horizontal cross wedge rolling mill.

6. A wedge cross-rolling forming method for ball parts, characterized in that: The forming method uses the wedge cross-rolling forming device for ball parts according to any one of claims 1 to 5, and the forming method comprises: S1, wedging stage: the metal bar is fed into the space defined by two guide plates between the upper die and the lower die, the wedge tips of the wedging sections of the upper die and the lower die correspond to each other, the upper die and the lower die rotate at the same speed and in the same direction, the two wedge tips wedge into the middle of the metal bar, driving the metal bar to rotate and roll; S2, forming stage: the convex ridges of the semi-forming holes of the upper die and the lower die extrude the metal bar. As the convex ridges of the forming section of the die rise, the metal bar is gradually formed into multiple ball parts with connecting necks by multiple forming holes during rotation and rolling; S3, finishing stage: multiple ball parts with connecting necks are rolled and finished in the forming hole of the finishing section of the mold to eliminate forming defects, improve roundness, and enhance the dimensional accuracy of the ball parts; S4, cutting stage: in the cutting section after the finishing section, the convex ridges are cut off to cut off the connecting necks between the ball parts to form a group of ball parts separated from each other; the upper mold and the lower mold return to the initial position at the same time to enter the next forming cycle.

7. The wedge cross-rolling forming method for ball parts according to claim 6, characterized in that: The forming method is used for hot forming, warm forming and cold forming processes, and the forming method is used for preparing ball parts with a size of φ1-φ100 mm.

Images