Die structure for reducing metal extrusion welding lines

Abstract

A die structure for reducing metal extrusion welding lines is divided into a male die and a female die, the male die is provided with shunting bridges and a die core, the female die is provided with a welding cavity, the front face of the welding cavity is in a petal shape, the shunting bridges and the welding cavity are evenly distributed in a radial shape, and after the shunting bridges and the welding cavity are oppositely combined, a complete shunting welding structure is formed. According to the utility model, the structure of the mold runner is optimized, the defects of welding lines of the produced metal extrusion product are greatly reduced, the grain size of the product is smaller, and the product performance is more excellent.

Description

Technical Field

[0001] The utility model relates to the technical field of metal material processing, in particular to a die structure for reducing metal extrusion welding lines. Background Art

[0002] When complex cavity materials such as pipes and profiles are extruded from metal materials, for products with high requirements for dimensional accuracy, etc., the forward extrusion method is generally adopted, and for extrusion dies, a split-flow combined die is used. Due to the split-flow effect of the split bridge in the die, the metal flow is split and then welded together, and finally a longitudinal welding line is formed on the product. Since many metal extrusion products need to be subjected to surface treatments such as oxidation and electrophoresis later, if the welding line of the product is too large or too deep, obvious welding line traces can easily appear on the surface of the product after surface treatment, and even an uneven feel is formed. Especially for square pipes, large-curved pipes, round pipes, etc. with a large aspect ratio, it is very difficult to avoid the welding line problem from the profile cross-section design. Therefore, reducing or alleviating the formation of welding lines in the extrusion stage is a technical problem to be solved in this field.

[0003] In actual production, technical personnel have proposed some improvement methods for the problem of extrusion welding line stripes through practical experience. The key technology to solve the extrusion welding line stripes is die design. Some scholars believe that during split-die extrusion, the metal deforms violently at the welding place, and the temperature rises sharply, resulting in coarse grains in the structure of the profile welding place. Or the die design is unreasonable, and the welding is not sufficient, resulting in the as-cast structure being brought into the extruded product. Or impurities, segregation tumors, etc. on the surface of the ingot are brought into the weld during the extrusion process, etc. But after efforts, this problem still cannot be solved well. The problem of batch scrapping of profiles due to the quality problem of welding line stripes often occurs. Summary of the Invention

[0004] The utility model provides a die structure for reducing metal extrusion welding lines, which optimizes the structure of the die runner. The metal extrusion products produced have significantly reduced welding line defects, smaller crystal grains of the products, and more excellent product performance.

[0005] In order to achieve the above objectives, the technical solution of the utility model is as follows:

[0006] A die structure for reducing metal extrusion welding lines, the die is divided into a punch and a die cavity. A split bridge and a die core are arranged on the punch, and a welding chamber is arranged in the die cavity. The front shape of the welding chamber is petal-shaped, and both the split bridge and the welding chamber are radially and evenly distributed. After the two are combined relatively, a complete split-flow welding structure is formed.

[0007] Traditional welding chambers are trapezoid-like or gear-shaped. The defect of their welding chambers lies in the fact that the filling amount of the metal fluid is too small, and during the process of the metal fluid flowing from a distance away from the forming runner to the forming runner, the pressure of the metal fluid does not increase rapidly, but smoothly enters the working zone of the mold, resulting in an unsatisfactory turbulent welding effect of the metal fluid. The petal-shaped welding chamber changes the defects of the traditional chamber. The cavity volume at the petal edge is larger, and the cross-sectional area of the chamber is smaller closer to the working zone. Such a design gradually pressurizes the metal fluid during the flow towards the working zone of the forming runner, making the welding effect better.

[0008] A drainage groove is provided between the bottoms of the welding chambers, and the position of the drainage groove corresponds and matches with the position of the shunt bridge. Initially, after the metal fluid is divided by the shunt bridge, a vacuum zone of the fluid is formed at the rear. The vacuum zone is the reason for the formation of the weld seam. The design of the drainage groove causes the metal fluid in the original vacuum zone to gather towards the drainage groove, making up for and eliminating the original vacuum zone, and trying to eliminate the phenomenon of the weld seam.

[0009] The shape of the drainage groove is Y-shaped, and the bottom of the Y-shape is connected to the working zone of the side wall of the mold outlet. The Y-shaped drainage groove converges the metal fluid on both sides towards the middle, supplementing the metal amount at the weld seam.

[0010] A retaining platform is provided at the position between adjacent drainage grooves.

[0011] When the retaining platform causes the metal fluid to flow towards the forming runner, turbulence occurs. The formation of turbulence stirs the fluid in the original neat vacuum zone, intensifying the fusion between metals and reducing the degree of weld seam formation. At the same time, the retaining platform also reduces the cross-sectional area of the metal runner, further increasing the fluid pressure in the welding chamber and enhancing the welding effect.

[0012] The shape of the retaining platform is arc-shaped and matches the shape of the working zone of the side wall of the mold outlet. The arc-shaped retaining platform also facilitates the flow of the metal fluid towards the drainage grooves on both sides.

[0013] Advantages of the utility model:

[0014] The utility model optimizes the design of the welding runner of the extrusion and shunt combined die, and the metal extrusion products produced have significantly reduced defects of the weld line. The weld line in the product is not visible to the naked eye not only in appearance but also very inconspicuous in the low-power experiment.

[0015] Due to more sufficient turbulence, the products produced by the mold of the utility model have smaller grain sizes and better mechanical properties of the products. Description of the drawings

[0016] Figure 1 It is a schematic side view of the mold decomposition structure;

[0017] Figure 2 Schematic front view structure of the punch; (extrusion direction)

[0018] Figure 3 Schematic front view structure of the die; (extrusion direction)

[0019] The names of the components in the attached drawings are: 1 - punch; 11 - dividing bridge; 12 - die core; 13 - dividing hole; 2 - die; 21 - welding chamber; 22 - drainage groove; 23 - retaining platform. Specific implementation mode Example 1

[0020] A die structure for reducing the metal extrusion welding line. The die is divided into a punch 1 and a die 2. A dividing bridge 11 and a die core 12 are arranged on the punch 1, and a welding chamber 21 is arranged on the die 2. The front shape of the welding chamber 21 is petal-shaped, and both the dividing bridge 11 and the welding chamber 21 are radially and evenly distributed. After the two are combined relatively, a complete dividing and welding structure is formed.

[0021] A drainage groove 22 is arranged between the bottoms of the welding chambers 21, and the position of the drainage groove 22 corresponds to and matches the position of the dividing bridge 11.

[0022] The shape of the drainage groove 22 is Y-shaped, and the bottom of the Y shape is connected to the working belt of the side wall of the die outlet.

[0023] Retaining platforms 23 are arranged at the positions adjacent to the drainage grooves 22.

[0024] The shape of the retaining platform 23 is arc-shaped and matches the shape of the working belt of the side wall of the die outlet.

Claims

1. A die structure for reducing metal extrusion bonding wires, characterized in that, The die is divided into a punch (1) and a die (2). A flow-dividing bridge (11) and a die core (12) are arranged on the punch (1), and a welding chamber (21) is arranged on the die (2). The front shape of the welding chamber (21) is petal-shaped. Both the flow-dividing bridge (11) and the welding chamber (21) are radially and uniformly distributed. After they are combined relatively, a complete flow-dividing and welding structure is formed.

2. The die structure for reducing metal extrusion bonding wires according to claim 1, characterized in that, A drainage groove (22) is arranged between the bottoms of the welding chambers (21), and the position of the drainage groove (22) corresponds to and matches the position of the flow-dividing bridge (11).

3. The die structure for reducing metal extrusion bonding wires according to claim 2, characterized in that, The drainage groove (22) is Y-shaped, and the bottom of the Y shape is connected to the working zone of the side wall of the die outlet.

4. The die structure for reducing metal extrusion bonding wires according to claim 2, characterized in that, A retaining platform (23) is arranged at the position between adjacent drainage grooves (22).

5. The die structure for reducing metal extrusion bonding wires according to claim 4, characterized in that The retaining platform (23) is arc-shaped and matches the shape of the working zone of the side wall of the die outlet.

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