CN107649529B - Bent member mistake is away from extrusion molding apparatus and method - Google Patents

Abstract

The invention relates to a device and method for staggered extrusion forming of curved components, relating to a device and method for extrusion forming of curved parts. The invention aims to solve a series of problems in the manufacturing process of the traditional bending member, such as many working procedures, poor flexibility, low production efficiency, and difficult quality control. In the method of the present invention, the integral punch of conventional extrusion is divided into two halves or more than two halves of the split structure, and the split punches are arranged and fixed according to a certain relative displacement, and then the blank is integrated Load forming, and can control the curvature change of the extruded curved member. It breaks through the single shape characteristic of long linear extrusion products, enriches the range of formable products, and tends to diversify the application fields. The method realizes the double functions of extrusion-bending integration in a single-pass extrusion process without additional additional processes, improves production efficiency, and reduces manufacturing costs. The invention is used for extrusion forming of curved components.

Description

Device and method for staggered extrusion forming of curved components

technical field

The invention relates to a metal extrusion forming method, in particular to a bending member offset extrusion forming method, and belongs to the technical field of bending member extrusion forming.

Background technique

Bending is a plastic processing method that bends blanks or semi-finished products such as plates, pipes, profiles, etc., into components with a certain angle or a certain shape with molds or other tools. It can achieve lightweight manufacturing effect and can meet various practical needs of structural parts with curvature in different shapes. Therefore, it is widely favored by aerospace, automobile, shipbuilding and other fields, and it is a green manufacturing technology.

At present, there are many processes for component bending, mainly including: press bending, roll bending, push bending, numerical control bending, local heating bending and laser bending, etc., but the process principles and characteristics of various methods are different, and these bending There are also some bottleneck problems in the forming methods, which limit the widening of the application range of the traditional bending process. For example, the cross-sectional shape of the bending part is prone to distortion during bending; the straight edge section of rolling bending will cause a lot of waste in mass production; push bending is mainly suitable for the processing of short bends with small bending radius and no straight section; laser Bending process requirements and costs are relatively high; CNC bending forming has certain requirements for bending radius and bending angle.

Bending components used in actual production are generally processed through multiple processes. Generally, the billet is first extruded into a product with the required cross-sectional shape, and then cold-formed, but it is difficult to guarantee the product forming quality and production efficiency, and the material utilization rate is low, and the production cost is expensive, which makes the application of bending components greatly restricted. limit. Therefore, shortening the processing flow, improving production efficiency and reducing manufacturing costs are the most effective ways to solve this problem. Based on the principle of pipe extrusion straightening, M. Kleiner et al. proposed a new method of extrusion forming of curved components, which mainly uses a moment at the die opening to form different friction forces to bend the extruded pipe; Klaus B.Müller et al. used different guide dies at the exit of the extrusion die to extrude curved profiles with complex cross-sectional shapes and fixed curvatures, which not only reduced the forming process, but also significantly improved the quality of the extruded products.

In view of the low production efficiency of traditional profile bending, difficulty in ensuring product size, and the cross-sectional deformation and surface scratches existing in the existing extrusion-bending integrated forming, the Chinese patent number is ZL201310224782.2, and the publication date is September 18, 2013 The patent for invention discloses a three-dimensional variable arc extruded profile on-line bending forming device. This patent designs a short-process processing method and device for bending profiles combined with online quenching and temperature control. By organically combining profile extrusion, bending and quenching The curved extrusion profile is produced, which not only has good formability, but also reduces defects such as springback, section deformation and surface scratches, and can also complete online quenching. However, additional auxiliary quenching devices are required and the process conditions are more demanding.

In addition, the invention patent with the Chinese patent number ZL201010528713.7 and the publication date of June 29, 2011 discloses a forming device for preparing pipe bending parts by differential extrusion of two convex dies. The lower speed difference is used to control the flow speed of the metal material at different outlet positions of the die, so as to form a pipe with a certain bending curvature. Because it is loaded in the same direction, the differential loading control of different punches is a difficult point that plagues the implementation; subsequently, the invention patent with the Chinese patent number ZL201010528701.4 and the publication date of June 29, 2011 discloses an extrusion surface For the method and device for forming small-angle bending pipe fittings on different curved surfaces, the patent provides a slope structure around the outlet of the mandrel to cause differences in the flow rate of the extruded metal, and the curved profile with the required curvature can be obtained. However, the design of the mold surface structure is demanding and difficult, and it is completely fixed and corresponding to the curvature of the extruded product. Once designed, it cannot be changed; the Chinese patent number is ZL201010156163.0, and the publication date is January 5, 2011. Invention patent Disclosed is a device that adopts concentric eccentric material extrusion molding to prepare pipe bending parts. In this patent, the cross-sectional shape around the perforating needle of the billet is processed into an asymmetric shape, that is, concentric eccentric material. The member is bent. When this method is implemented, not only the shape of the blank needs to be specially designed, but also the matching extrusion barrel, punch and other structures need to be completely correspondingly processed and manufactured. Once the curvature of the product changes, the tooling structure needs to be redesigned.

Since the curvature shape of the curved member is characterized by continuous changes, the above patents not only require additional auxiliary tooling or precise design of the blank and mold structure, but also have poor process flexibility, cumbersome processing procedures, high technical difficulty and high cost, and cannot meet the needs of the industry. The requirement to realize the dynamic adjustment of the curvature of the extruded product in the single-pass extrusion process.

Contents of the invention

The purpose of the present invention is to provide a bending member staggered extrusion forming method to solve a series of bottleneck problems such as difficult manufacturing process of the traditional bending member, poor flexibility, difficulty in quality assurance, and high cost. The tooling structure of this method is simple, the curvature of the extruded product can be adjusted in real time, the process flexibility and forming quality are good, and the microstructure and performance of the extruded product are also affected to a certain extent.

The present invention is achieved through the following technical solutions:

Apparatus: A bending member staggered extrusion forming apparatus of the present invention includes a positioning hole 1, a left punch 2, a right punch 3, a positioning pin 4, an extrusion cylinder 5, a blank 6, a mandrel 7 and a base 8. The key to the structure of the device lies in the design and positioning relationship of each part of the punch. A plurality of equidistant positioning holes 1 are set on both sides of the left punch 2 and the right punch 3 respectively. According to the needs of the bending curvature change of the extruded part, the left punch 2 and the right punch 3 are placed at a certain distance apart, and the The positioning pin 4 is inserted into the hole corresponding to the left punch 2 and the right punch 3, so that the offset h of the relative positions of the left punch 2 and the right punch 3 is fixed.

Method: The method is achieved through the following steps:

Step 1. According to the curvature requirements of the bending member, place the left punch 2 and the right punch 3 according to the preset offset amount h, and insert the positioning pin 4 into the positioning position at the same position of the left punch 2 and the right punch 3 in hole 1. Positioning holes 1 are respectively set on the left punch 2 and the right punch 3, the number is generally ≥ 3, and the distance between adjacent positioning holes 1 on the punches is set according to the curvature of the bending member;

Step 2, placing the base 8 on the workbench of the press;

Step 3, placing the extruding cylinder 5 above the base 8 and fixing it;

Step 4, put the mandrel 7, the blank 6 and the complete combination of the left punch 2 and the right punch 3 fixed by the positioning pin 4 into the extrusion cylinder 5 in sequence;

Step 5, use the lower table of the press to apply load downwards, the combination of the left punch 2 and the right punch 3 loads the blank 6, and extrudes the product with curvature until the blank 6 is completely extruded;

Step 6: Remove the combination of the left punch 2 and the right punch 3 and the mandrel 7, and take out the extruded product with curvature.

Compared with the prior art, the inventive method has the following beneficial effects:

1. The innovation of the present invention is that after dividing the integral punch of conventional extrusion into two halves or more than two halves of the split structure, they are arranged at staggered distances according to the preset relative displacement and fixed, and then use the combination The punch can carry out integral loading and forming on the billet, and then the bent extrusion member can be obtained;

2. Due to the staggered arrangement and fixing method between different split punches, the order in which they contact the blank during the loading process has changed, resulting in a change in the flow sequence of the extruded metal. The curvature of the bending member in extrusion molding can be regulated through the adjustment and change of the offset h of the split punch;

3. This method realizes the broadening and in-depth development of the application field of conventional extrusion technology, breaks through the single shape feature of traditional extrusion products, which are mostly long and straight, and enriches the types of products that can be formed by existing extrusion technology, and the application field also tends to be more diversified;

4. Only through the design and adjustment of the punch structure, the dual effect of extrusion-bending integration can be realized in a single-pass extrusion process without additional additional processes, and the bending curvature and shape of the component can be customized Good performance, no rebound and high quality control accuracy;

5. Staggered extrusion technology is also suitable for the processing and manufacturing of curved components with continuous curvature changes. It has low process requirements, good flexibility, low cost and easy implementation.

Description of drawings

Figure 1 is the main cross-sectional view of the structure of the staggered extrusion device for bending members (the number of punches is 2).

Figure 2 is the main cross-sectional view of the bending member at the initial stage of staggered extrusion (the number of punches is 2).

Figure 3 is the main sectional view of the bending member at the end of staggered extrusion (the number of punches is 2).

Figure 4 is the main cross-sectional view of the structure of the staggered extrusion device for bending members (the number of punches is 3 and the staggered distance between the left punch and the middle punch is equal to the staggered distance between the middle punch and the right punch).

Figure 5 is the main cross-sectional view of the bending member at the initial stage of offset extrusion (the number of punches is 3 and the offset between the left punch and the middle punch is equal to the offset between the middle punch and the right punch).

Figure 6 is the main cross-sectional view of the bending member at the end of offset extrusion (the number of punches is 3 and the offset between the left punch and the middle punch is equal to the offset between the middle punch and the right punch).

Figure 7 is the main cross-sectional view of the structure of the bending member staggered extrusion device (the number of punches is 3 and the staggered amount of the left punch and the middle punch is <h/2, and the staggered amount of the middle punch and the right punch>h/2 ).

Figure 8 is the main cross-sectional view of the bending member at the initial stage of offset extrusion (the number of punches is 3 and the offset between the left punch and the middle punch is <h/2, and the offset between the middle punch and the right punch is>h/2 ).

Figure 9 is the main cross-sectional view of the bending member at the end of the staggered extrusion (the number of punches is 3 and the staggered amount of the left punch and the middle punch is <h/2, and the staggered amount of the middle punch and the right punch>h/2 ).

Figure 10 is the main cross-sectional view of the structure of the staggered extrusion device for bending members (the number of punches is 3 and the staggered distance between the left punch and the middle punch is > h/2, and the staggered distance between the middle punch and the right punch is < h/2 ).

Figure 11 is the main cross-sectional view of the bending member at the initial stage of offset extrusion (the number of punches is 3 and the offset between the left punch and the middle punch is > h/2, and the offset between the middle punch and the right punch is < h/2 ).

Figure 12 is the main cross-sectional view of the bending member at the end of the staggered extrusion (the number of punches is 3 and the staggered distance between the left punch and the middle punch is > h/2, and the staggered amount between the middle punch and the right punch is < h/2 ).

Fig. 13 is a front sectional view and a left side view of the punch structure.

Detailed ways

Specific Embodiment 1: This embodiment is described with reference to FIGS. 1 to 3 . In this embodiment, the punch is designed as a left-right symmetrical two-part structure. This embodiment includes: a positioning hole 1 , a left punch 2 , a right punch 3 , a positioning pin 4 , an extrusion barrel 5 , a blank 6 , a mandrel 7 and a base 8 . This embodiment is completed by the following steps: 1. Make the punch into two parts, the left punch 2 and the right punch 3; 2. Stagger the left punch 2 and the right punch 3 according to the curvature of the required bending member. The distance h is placed, and the positioning pin 4 is inserted into the positioning hole 1 between the two punches to fix it; 3. Fix the base 8 on the press workbench; 4. Place the extrusion cylinder 5 above the base 8; 5. 1. Put the mandrel 7, the blank 6, the combination of the left punch 2 fixed with the positioning pin 4 and the right punch 3 in the extrusion cylinder 5 in turn; six, load the combined punch, the left punch 2 and the right punch 3 in turn contact with the blank 6 and begin to undergo plastic deformation, and gradually extrude a curved member with a certain curvature from the core die until the blank is completely extruded; 7. When the end of the punch reaches the bottom of the extrusion cylinder , which is the end of forming. Remove the combination of the left punch 2 and the right punch 3 and the core mold 7 in sequence, and take out the extruded product.

Specific embodiment two: This embodiment is described in conjunction with Figures 4 to 6. The punch in this embodiment is designed as a three-part structure. This embodiment includes: positioning hole 1, left punch 2, right punch 3, positioning pin 4, Extrusion cylinder 5, billet 6, mandrel 7 and base 8, middle punch 9. This embodiment is completed by the following steps: 1. Set the left punch 2, the middle punch 9 and the right punch 3 at staggered distances according to the curvature of the required bending parts, and the adjacent punches are staggered by a certain distance h/ 2. Fix it with positioning pin 4; 2. Fix the base 8 on the press table; 3. Place the extrusion cylinder 5 above the base 8; 4. Put the core mold 7 into the extrusion cylinder 5 in sequence , blank 6, the combination of left punch 2, middle punch 9 and right punch 3 fixed by positioning pin 4; five, the combined punch is loaded, left punch 2, middle punch 9 and right punch The head 3 contacts the blank 6 in turn and begins to undergo plastic deformation, and gradually extrudes a curved member with a certain curvature from the mandrel until the blank is completely extruded into shape; 6. When the end of the punch reaches the bottom of the extrusion cylinder, it is Forming is over. Remove the combination of the left punch 2, the middle punch 9 and the right punch 3 and the mandrel 7 in sequence, and take out the extruded product.

Specific embodiment three: This embodiment is described in conjunction with Figures 7 to 9. The punch in this embodiment is designed as a three-part structure. This embodiment includes: positioning hole 1, left punch 2, right punch 3, positioning pin 4, Extrusion cylinder 5, billet 6, mandrel 7 and base 8, middle punch 9. Wherein, the stagger amount between the left punch 2 and the middle punch 9 is <h/2, and the stagger amount between the middle punch 9 and the right punch 3>h/2. Other connection relationships are the same as those in the second embodiment.

Specific embodiment four: This embodiment is described in conjunction with Figures 10 to 12. The punch in this embodiment is designed as a three-part structure. This embodiment includes: positioning hole 1, left punch 2, right punch 3, positioning pin 4, Extrusion cylinder 5, billet 6, mandrel 7 and base 8, middle punch 9. Wherein, the stagger amount between the left punch 2 and the middle punch 9>h/2, and the stagger amount between the middle punch 9 and the right punch 3<h/2. Other connection relationships are the same as those in the second embodiment.

Claims (5)

1. A bending member staggered extrusion forming device, characterized in that: the device includes a positioning hole (1), a left punch (2), a right punch (3), a positioning pin (4), an extrusion cylinder (5), blank (6), mandrel (7) and base (8), wherein, the conventional integral punch is divided into left punch (2) and right punch (3) two parts, left punch (2) A plurality of positioning holes (1) are respectively equidistant from the substrate of the right punch (3), and the left punch (2) and the right punch (3) are staggered according to the requirements of the curvature change of the bending member, and the The positioning pin (4) in the positioning hole (1) fixes the stagger h of the relative positions of the left punch (2) and the right punch (3). 2. A bending member staggered extrusion forming device according to claim 1, characterized in that: the conventional integral punch is divided into a left punch (2), a right punch (3) and a middle punch (9) It consists of three parts. 3. A method of using the device according to claim 2 to realize staggered extrusion forming of bending members, characterized in that: said method is realized through the following steps: Step 1. Arrange the left punch (2), the middle punch (9) and the right punch (3) at the same staggered distance according to the curvature of the required bending piece, and the staggered distance between adjacent punches is h /2, and fix it with positioning pin (4); Step 2, fixing the base (8) on the workbench of the press; Step 3, placing the extruding cylinder (5) above the base (8); Step 4: Put the mandrel (7), the billet (6), the fixed left punch (2), the middle punch (9) and the right punch (3) into the extrusion cylinder (5) sequentially ; Step 5: Load the combination punch, the left punch (2), the middle punch (9) and the right punch (3) contact the blank (5) in sequence and begin to undergo plastic deformation, and gradually extrude from the core die Bending members with a certain curvature until the blank is completely extruded into shape; Step 6: Remove the combination of left punch (2), middle punch (9) and right punch (3) and core mold (7) in sequence, and take out the extruded curved member. 4. A bending member offset extrusion forming method according to claim 3, characterized in that: the left punch (2), the middle punch (9) and the right punch (3) in the first step They are all staggered and arranged at a certain distance from each other, wherein, the stagger amount between the left punch (2) and the middle punch (9) is <h/2, and the distance between the middle punch (9) and the right punch (3) The amount of misalignment between >h/2. 5. A bending member offset extrusion forming method according to claim 3, characterized in that: the left punch (2), the middle punch (9) and the right punch (3) in the first step They are all staggered and arranged at a certain distance from each other, wherein, the stagger amount between the left punch (2) and the middle punch (9)>h/2, and the distance between the middle punch (9) and the right punch (3) The amount of misalignment between <h/2.