Method for controlling precision forging forming
By designing the preset hole defect-reducing structure and applying the volume unchanging principle in precision forging, the molding quality problems caused by the complex structure of the forging cavity are solved, and the defect-free molding and cost reduction are achieved.
Patent Information
- Application Number
- CN202510278566.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-10
- Publication Date
- 2025-06-20
AI Technical Summary
During the precision forging molding process, the complex structure of the forging inner cavity leads to interference, resulting in quality problems such as unfilled, folded, and deformation. Especially in the process of deep cavity forging molding, traditional isothermal forging molding methods are difficult to achieve defect-free molding.
Through equal volume forming calculation method, a preset hole defect reduction structure is designed, and the volume constant principle is applied during the material forming process, and the hole groove is divided into two major directions of inward and outward flow. Through equal volume calculation and material flow trend, the volume is allocated to ensure that the material is effectively controlled during the molding process and avoiding folding and unsatisfactory defects.
It realizes defect-free molding on non-processing surfaces in precision forging, reduces machine-added costs, improves product comprehensive performance, and expands the application scope of this method, and is suitable for other die forgings with complex structures.
Smart Images
Figure CN120170019A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of precision die forging, and particularly relates to a method for controlling precision forging forming. Background Art
[0002] Precision forging forming technology is a new forging forming technology based on the ordinary forging forming process. Precision forging forming has the advantages of energy saving, material saving, high precision and high performance. At the same time, there are also difficulties in forging part forming. One is that due to the complex internal cavity structure of the forging part, interference is likely to occur in each part while ensuring the non-machined surface, resulting in quality problems such as incomplete filling, folding and deformation of each part of the internal cavity of the forging part; the other is that the internal cavity of the forging part is relatively deep, and it is difficult to eliminate the defects generated in the forging forming process by turning and grinding means. Therefore, defect-free forming must be achieved.
[0003] The main defects of the precision forging deep cavity hub produced by the currently traditional isothermal forging forming method are that each part at the bottom of the cavity is not fully filled, folded and deformed. The main reason for this is that in the forming process of complex deep cavity forgings, due to the easy mutual interference of each structural part inside the forging cavity, quality problems such as folding and deformation caused by uneven material distribution and excessive deformation occur.
[0004] Therefore, a method for controlling precision forging forming is needed to solve the above problems. Summary of the Invention
[0005] The present invention provides a method for controlling precision forging forming, which realizes defect-free forming of the relief hole part on the non-machined surface through an equal-volume forming calculation method to solve the existing problems.
[0006] The method for controlling precision forging forming of the present invention adopts the following technical solutions, including: Upsetting and rounding the blank to obtain a hub blank; Rough machining the hub blank and machining the center hole of the hub to obtain a rough machined part; Performing a first isothermal die forging on the rough machined part to form the rim, rim, web, guide rail and bearing cavity of the hub to obtain a first isothermal die forging; Performing a first isothermal die forging on the first isothermal die forging to form the rim boss of the hub and a preset relief hole defect structure to obtain a second isothermal die forging; Performing a first isothermal die forging on the second isothermal die forging to supplement the downward pressing material during the isothermal die forging of the second isothermal die forging outward into the preset relief hole defect structure to obtain a precision hub.
[0007] Preferably, the steps of the hub blank are: Upsetting the free end of the blank; rounding the outer peripheral surface of the blank and leaving a machining allowance to obtain a hub blank.
[0008] Preferably, the steps of obtaining the rough workpiece are as follows: Turn off the machining allowances left on the upper end face, lower end face, and outer circle of the hub blank; Bore and ream the center of the hub to obtain the center hole of the hub, that is, obtain the rough workpiece.
[0009] Preferably, the steps of performing one-time isothermal forging on the rough workpiece are as follows: Place the rough workpiece into the first pre-forging die to perform one-time isothermal forging to obtain the first isothermal forging. Among them, the first pre-forging die is used to form the rim, wheel rim, web, guide rail, and bearing cavity of the hub.
[0010] Preferably, the steps of performing one-time isothermal forging on the first isothermal forging are as follows: Place the first isothermal forging into the second pre-forging die to perform one-time isothermal forging to obtain the second isothermal forging. Among them, the second pre-forging die is used to form the rim boss and the preset relief hole defect structure of the hub.
[0011] Preferably, the steps of constructing the preset relief hole defect structure are as follows: Adopt three-dimensional model Boolean operation to design a relief hole defect structure with a depth of 1 mm around the relief hole and larger than the relief hole. Among them, the material flowing outwards when the final relief hole is formed is equal to the volume of the preset relief hole defect structure.
[0012] Preferably, use the third pre-forging die to perform one-time isothermal forging on the second isothermal forging to obtain a precision hub. Among them, the third pre-forging die is used to extrude the downward pressing material during the isothermal forging of the second isothermal forging into the preset relief hole defect structure.
[0013] Preferably, after performing one-time isothermal forging on the second isothermal forging, it further includes: turning off the boss at the large end of the rim of the hub.
[0014] The beneficial effects of the present invention are as follows: 1. In the precision forging forming process of the present invention, most of the non-machined surfaces in the part cavity are retained in the final precision forging hub forging: namely, the bolt table surface, relief hole surface, and bearing cavity surface. The metal streamline of the forging is retained along the outer shape without being cut off. While improving the comprehensive performance of the product, the machining cost of the product is greatly reduced; in addition, the precision forging forming method of the present invention has a wide range of applications and can be applied to other die forgings with complex structures and deep cavities. It can be used for reference in the production of deep cavity structures with complex structures. Shorten the technical research and development time, stabilize the production quality of new products, reduce the production cycle of new products, and ensure the comprehensive performance of forgings.
[0015] 2. The present invention pre-determines the relief hole defect structure on the non-machined surface of the precision hub by fine die forging, and designs and adopts the principle of constant volume during the material forming process. The existing relief hole grooves are divided into two major directions of inward and outward flow according to the material flow trend. By performing equal volume calculation on the relief hole grooves and distributing the volume according to the material flow trend, a water droplet-shaped material bin is designed for the inward flow, and the pre-defect structure of the relief hole is designed for the outward flow material in the second isothermal forging. Finally, when forming the relief hole, it is ensured that the inward and outward material flows can be effectively controlled, avoiding defects such as folding and incomplete filling, thereby ensuring the forging accuracy. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.
[0017] Figure 1 It is a flowchart of a method for controlling precision forging forming of the present invention; Figure 2 It is a schematic structural diagram during the hub forming process in an embodiment of the present invention; Figure 3 It is a three-dimensional structural diagram during the hub forming process in an embodiment of the present invention; Figure 4 It is a schematic structural diagram of the final hub processed in an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS
[0018] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.
[0019] An embodiment of a method for controlling precision forging forming of the present invention, as Figure 1 shown, includes: S1. Upset and roll the blank to obtain a hub blank; Exemplarily, in a specific embodiment, taking a blank with a size of Φ300×370±2 as an example, that is, the diameter of the blank is 300 mm and the length is 370±2 mm. The blank is upset and rolled to obtain a hub blank with a size of Φ502±5×130±4, that is, the diameter of the hub blank is Φ502±5 mm and the length of the hub blank is 130±4 mm. Among them, a rough machining allowance of 4 mm is reserved on one side.
[0020] S2. Rough machine the hub blank; Specifically, rough machine the hub blank and machine the center hole of the hub to obtain a rough machined part.
[0021] Exemplarily, in a specific embodiment, machine the machining allowances left on the upper end face, lower end face, and outer circle of the hub blank; bore and ream the center of the hub to obtain the center hole of the hub, that is, obtain a rough machined part as shown in Figure 2 a.
[0022] S3. Perform a first isothermal forging on the rough machined part to obtain a first isothermal forging; Exemplarily, in a specific embodiment, use a first pre-forging die to perform a first isothermal forging on the rough machined part to obtain a first isothermal forging as shown in Figure 2 b. The first pre-forging die is used to form the rim, rim flange, web, guide rail, and bearing cavity of the hub.
[0023] S4. Perform a second isothermal forging on the first isothermal forging to obtain a second isothermal forging; Exemplarily, in a specific embodiment, use a second pre-forging die to perform a second isothermal forging on the first isothermal forging to obtain a second isothermal forging as shown in Figure 2 c. The second pre-forging die is used to form the rim flange boss and a preset relief hole defect structure of the hub.
[0024] Among them, the steps to construct the preset relief hole defect structure are as follows: adopt three-dimensional model Boolean operation, design a relief hole defect structure with a depth of 1 mm and larger than the relief hole around the relief hole. The outer contour of the relief hole defect structure is distributed in an isometric line with the outer contour of the relief hole. Among them, the material flowing outwards during the final forming of the relief hole is equal to the volume of the preset relief hole defect structure (i.e., the equal volume algorithm).
[0025] Among them, as shown in Figure 2 c, after performing a second isothermal forging on the second isothermal forging, it further includes: machining the boss at the large end of the rim of the hub.
[0026] S5. Perform a third isothermal forging on the second isothermal forging to obtain a precision hub; Exemplarily, in a specific embodiment, the second isothermal forging part is subjected to one-time isothermal forging by using a third pre-forging die to obtain a precision wheel hub as shown in Figure 2 d. The third pre-forging die is used to extrude the downward blanking material during the isothermal forging of the second isothermal forging part outward into a preset reduced-hole defect structure.
[0027] Among them, the three-dimensional structure schematic diagrams during the processing from step S1 to step S5 are as shown in Figure 3 ; after step S5, the reduced-hole pre-defect structure is removed to machine the reduced hole, and the final wheel rail is as shown in Figure 4 .
[0028] It should be noted that the design of the reduced hole on the non-machining surface of the precision wheel hub of the present invention adopts the principle of constant volume during the material forming process. The existing reduced-hole grooves are divided into two major directions of inward and outward flow according to the material flow trend. By performing equal-volume calculation on the reduced-hole grooves and distributing the volume according to the material flow trend, a water-drop-shaped material bin is designed for the inward flow, and the material flowing outward is designed with a reduced-hole pre-defect structure in the second isothermal forging part. Finally, when forming the reduced hole, it is ensured that the inward and outward material flows can be effectively controlled, avoiding the occurrence of defects such as folding and incomplete filling.
[0029] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.
Claims
1. A method for controlling precision forging, characterized in that: include: The blank is subjected to upsetting and rounding to obtain a wheel hub blank; Performing rough machining on the wheel hub blank and machining the center hole of the wheel hub to obtain a rough machined part; Performing isothermal die forging on the rough-machined part to form the wheel rim, wheel rim, wheel belly, guide rail and bearing cavity of the wheel hub to obtain a first isothermal die forging part; Performing isothermal die forging once on the first isothermal die forging to form a wheel rim boss of the wheel hub and a preset hole defect reduction structure to obtain a second isothermal die forging; The second isothermal die forging is isothermally forged once, so as to supplement the pressed material of the second isothermal die forging to the preset hole defect reduction structure, thereby obtaining a precision wheel hub.
2. A method for controlling precision forging according to claim 1, characterized in that: The steps of wheel hub blank are: The free end of the blank is upset; the outer peripheral surface of the blank is rounded with a processing allowance to obtain a hub blank.
3. A method for controlling precision forging according to claim 1, characterized in that: The steps to obtain the rough machined part are: Remove the machining allowance from the upper end face, lower end face and outer circle of the wheel hub blank; The center of the hub is bored and expanded to obtain the center hole of the hub, that is, a rough-machined part.
4. A method for controlling precision forging according to claim 1, characterized in that: The steps for isothermal forging of rough machined parts are as follows: The rough-machined part is placed in a first pre-forging die for isothermal forging to obtain a first isothermal forging part, wherein the first pre-forging die is used to form the wheel rim, wheel rim, wheel belly, guide rail and bearing cavity of the wheel hub.
5. A method for controlling precision forging according to claim 1, characterized in that: The steps of performing isothermal die forging on the first isothermal die forging are: The first isothermal die forging is placed in a second pre-forging die and isothermally forged to obtain a second isothermal die forging, wherein the second pre-forging die is used to form a wheel rim boss of the wheel hub and a preset hole defect reduction structure.
6. A method for controlling precision forging according to claim 5, characterized in that: The steps to construct a preset hole defect mitigation structure are: By using Boolean operation of a three-dimensional model, a lightening hole defect structure with a depth of 1 mm and greater than the lightening hole is designed around the lightening hole, wherein the material flowing outward when the lightening hole is finally formed is equal to the volume of the preset lightening hole defect structure.
7. A method for controlling precision forging according to claim 1, characterized in that: The second isothermal die forging is isothermally forged using the third pre-forging die to obtain a precision wheel hub, wherein the third pre-forging die is used to extrude the lower pressing material of the second isothermal die forging into a preset hole defect reduction structure when the second isothermal die forging is isothermally forged.
8. A method for controlling precision forging according to claim 1, characterized in that: After the second isothermal die forging is performed once, the method further includes: machining and removing the boss at the large end of the wheel rim of the wheel hub.