Closed forging process for flange plate of hub unit

Abstract

The invention provides a hub unit flange plate closed type forging process which sequentially comprises the procedures of blanking, upsetting, first-time forward extrusion, second-time forward extrusion, forming and punching, materials are distributed on the basis of the minimum rod size of the lower end of a workpiece in the first-time forward extrusion procedure, and a rod portion of the lower end of the workpiece is formed preferentially in the second-time forward extrusion procedure. In the forming process, the upper end and the lower end of the workpiece are filled with the materials firstly, and then the disc face of the workpiece is filled with the materials finally. The method has the advantages of improving the product qualification efficiency, reducing the production cost and the like.

Description

Technical Field

[0001] The invention relates to the field of mold processing, and in particular to a closed forging process for a hub unit flange. Background Art

[0002] The hub unit flange is an important part of the automobile wheel hub. The existing hub unit flange forging process is generally a multi-station precision forming hot die forging process. The forging process is divided into: blanking-heating-upsetting-positive extrusion-preforming-forming-punching. During the process, the shape of the process product is designed in the original way. The positive extrusion process squeezes the second rod diameter in the middle of the lower end of the workpiece, and the preforming process squeezes the first rod diameter at the lower part of the lower end of the workpiece and distributes the material. The forming process needs to form the first rod diameter, reverse extrude the upper end diameter and upsetting the large disk surface, but the previous process failed to fill the first rod diameter and the contact time between the forming upper die and the blank was short, which caused the upper and lower end faces of the formed product to collapse, and the machining could not completely remove the black skin, resulting in product scrapping.

[0003] Therefore, it is necessary to provide a new technical solution. Summary of the invention

[0004] In order to solve the technical problems existing in the prior art, the present invention discloses a closed forging process for a hub unit flange, and the specific technical solution is as follows:

[0005] The present invention provides a closed forging process for a hub unit flange, which sequentially includes blanking, upsetting, first positive extrusion, second positive extrusion, forming and punching processes.

[0006] In the first forward extrusion process, the material is distributed based on the minimum rod size at the lower end of the workpiece.

[0007] In the second forward extrusion process, the rod at the lower end of the workpiece is formed first, and then the material is distributed to the disk surface and the upper end.

[0008] In the forming process, the upper and lower ends of the workpiece are filled first, and then the workpiece disc surface is filled last.

[0009] Furthermore, the minimum rod diameter at the lower end of the workpiece in the first forward extrusion process is 0.5 mm / single side smaller than the minimum rod diameter at the lower end of the workpiece in the second forward extrusion process; the minimum rod diameter at the lower end of the workpiece in the second forward extrusion process is 0.5 mm / single side smaller than the minimum rod diameter at the lower end of the workpiece in the forming process.

[0010] Furthermore, in the second forward extrusion process, the minimum diameter of the upper end of the workpiece is smaller than the maximum diameter of the rod portion at the lower end of the formed workpiece.

[0011] Furthermore, in the second forward extrusion process, the diameter of the center hole at the upper end of the workpiece is larger than the diameter of the corresponding upper die punch.

[0012] Furthermore, the height of the upper end of the workpiece in the second forward extrusion process is higher than the height of the upper end of the formed workpiece plus the thickness of the disk surface.

[0013] The present invention has the following beneficial effects:

[0014] 1. The closed forging process for the hub unit flange provided by the present invention controls the material flow direction through two forward extrusion processes, so that the upper and lower ends of the workpiece are filled first, and then the material flows to the disk surface, ensuring that there is no collapse angle on the end face of the workpiece, thereby improving product qualification efficiency and reducing production costs.

[0015] 2. The closed forging process for the hub unit flange provided by the present invention sets the diameter of the center hole larger than the punch diameter in the second forward extrusion, so that the center hole plays an auxiliary guiding role for the forming upper die during the forming process.

[0016] 3. In the closed forging process for the hub unit flange provided by the present invention, the upper end height in the second forward extrusion is higher than the upper end height of the formed product plus the disc thickness, thereby increasing the contact time between the forming upper die and the blank, and better extruding the upper end surface and the formed workpiece disc surface.

[0017] 4. In the closed forging process for the hub unit flange provided by the present invention, the minimum diameter of the upper end of the workpiece in the second forward extrusion process is smaller than the maximum diameter of the lower end rod of the formed workpiece, which is beneficial for the material to preferentially fill the transition part connecting the lower end rod and the disk surface during forming.

[0018] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 It is a process flow chart of multi-station closed forming of a hub unit flange provided by an embodiment of the present invention.

[0021] Among them, a, blanking; b, upsetting; c, first positive extrusion; d, second positive extrusion; e, forming; f, punching;

[0022] D1, the outer diameter of the upper end of the first positive extrusion c; d1, the minimum rod diameter of the lower end of the first positive extrusion c;

[0023] D2, the maximum outer diameter of the upper end of the second positive extrusion d; X1, the minimum outer diameter of the upper end of the second positive extrusion d; H1, the height of the upper end of the second positive extrusion d; d2, the minimum rod diameter of the lower end of the second positive extrusion d;

[0024] X2, the maximum diameter of the lower end of the formed e; d3, the minimum diameter of the lower end of the formed e; H2, the height of the upper end of the formed e plus the thickness of the disk. DETAILED DESCRIPTION

[0025] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0026] In the description of the present invention, it should be understood that the terms "upper", "lower", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In the description of the present invention, "plurality" means two or more, unless otherwise clearly and specifically defined.

[0027] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0028] A closed forging process for hub unit flange, reference Figure 1 , which includes blanking, upsetting, first positive extrusion, second positive extrusion, forming and punching processes in sequence.

[0029] In the first forward extrusion process, the material is distributed based on the minimum rod size at the lower end of the workpiece. In the second forward extrusion process, the rod at the lower end of the workpiece is formed first, and then the material is distributed to the disk surface and the upper end. In the forming process, the upper and lower ends of the workpiece are filled first, and then the workpiece disk surface is filled last.

[0030] The minimum rod diameter at the lower end of the workpiece in the first forward extrusion process is 0.5 mm / single side smaller than the minimum rod diameter at the lower end of the workpiece in the second forward extrusion process; the minimum rod diameter at the lower end of the workpiece in the second forward extrusion process is 0.5 mm / single side smaller than the minimum rod diameter at the lower end of the workpiece in the forming process.

[0031] In the second forward extrusion process, the minimum diameter of the upper end of the workpiece is smaller than the maximum diameter of the rod at the lower end of the formed workpiece.

[0032] In the second forward extrusion process, the diameter of the center hole at the upper end of the workpiece is larger than the diameter of the corresponding upper die punch.

[0033] In the second forward extrusion process, the upper end height of the workpiece must be higher than the upper end height of the formed workpiece plus the thickness of the disk surface.

[0034] In one embodiment, reference Figure 1 The formed workpiece includes the disk in the middle, the upper end above the disk and the lower end below the disk. The lowest part of the lower end is the minimum rod diameter, and the junction between the lower end and the disk is the maximum rod diameter of the lower end. The dimensions marked in the attached drawings are: D1, the upper end outer diameter of the first positive extrusion c; d1, the minimum rod diameter of the lower end of the first positive extrusion c; D2, the maximum outer diameter of the upper end of the second positive extrusion d; X1, the minimum outer diameter of the upper end of the second positive extrusion d; H1, the upper end height of the second positive extrusion d; d2, the minimum rod diameter of the lower end of the second positive extrusion d; X2, the maximum rod diameter of the lower end of the formed e; d3, the minimum rod diameter of the lower end of the formed e; H2, the upper end height of the formed e plus the disk thickness.

[0035] The forging process of the present application reversely designs the shape and size of each process from the size of the final formed workpiece, thereby obtaining the product shapes of the forming, second positive extrusion, first positive extrusion, upsetting and other processes in sequence. During the design process, the minimum rod diameter of the previous process is 0.5 mm / single side smaller than the minimum rod diameter of the subsequent process, for example, d3≥d2+1≥d1+2.

[0036] On this basis, in order to increase the control over the material flow, in the processes of the first positive extrusion c and the second positive extrusion d, it is necessary to further constrain the shape and size of these two processes. In the second positive extrusion d, the minimum outer diameter X1 of the upper end of the workpiece should be slightly smaller than the diameter X2 of the intersection of the lower end rod and the disk surface of the forming e, for example, X2 ≥ X1 + 1. The upper end height H1 of the workpiece in the second positive extrusion d should be greater than the upper end height in the forming e plus the disk thickness H2, for example, H2 ≤ H1 + 5. The upper end outer diameter D1 of the product in the first positive extrusion c should be smaller than the upper end outer diameter D2 of the second positive extrusion d, for example, D2 ≥ D1 + 4.

[0037] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example" or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine different embodiments or examples described in this specification.

[0038] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify and vary the above embodiments within the scope of the present invention.

Claims

1. A closed forging process for a hub unit flange, characterized in that: It includes blanking, upsetting, first extrusion, second extrusion, forming and punching processes. In the first forward extrusion process, the material is distributed based on the minimum rod size at the lower end of the workpiece. In the second forward extrusion process, the rod at the lower end of the workpiece is formed first, and then the material is distributed to the disk surface and the upper end. In the forming process, the upper and lower ends of the workpiece are filled first, and then the workpiece disc surface is filled last.

2. The closed forging process for the hub unit flange according to claim 1, characterized in that: The minimum rod diameter at the lower end of the workpiece in the first forward extrusion process is 0.5 mm / single side smaller than the minimum rod diameter at the lower end of the workpiece in the second forward extrusion process; the minimum rod diameter at the lower end of the workpiece in the second forward extrusion process is 0.5 mm / single side smaller than the minimum rod diameter at the lower end of the workpiece in the forming process.

3. The closed forging process for the hub unit flange according to claim 2 is characterized in that: In the second forward extrusion process, the minimum diameter of the upper end of the workpiece is smaller than the maximum diameter of the rod at the lower end of the formed workpiece.

4. The closed forging process for the hub unit flange according to claim 1, characterized in that: In the second forward extrusion process, the diameter of the center hole at the upper end of the workpiece is larger than the diameter of the corresponding upper die punch.

5. The closed forging process for the hub unit flange according to claim 1, characterized in that: In the second forward extrusion process, the upper end height of the workpiece must be higher than the upper end height of the formed workpiece plus the thickness of the disk surface.

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