Design Techniques for Aluminum Profile Extrusion Molds

The design tips for aluminum profile extrusion molds are as follows:

1. Determine the design mold cavity parameters:

1. Identify the machine: Choose the appropriate machine based on the extrusion ratio, maximum outer diameter of the profile section, and complexity.

2. Determine mold specifications: Larger specifications for large section molds are preferable to enhance stability.

3. Design mold holes and related structures: Reasonably distribute diverging holes, design guide plates, work belts, and forming holes.

2. Reasonable Arrangement of Mold Holes:

1. Single Hole Mold: The theoretical center of the hole is placed at the center of the mold; thin-walled or difficult-to-form sections are close to the center.

2. Multi-Hole Mold: Arranged as much as possible on the concentric circumference to ensure symmetry, taking into account both the strength of the mold and the uniform flow of metal.

3. Calculation of Die Hole Size：

1. Considerations: alloy composition, product size tolerance, thermal expansion coefficient, extrusion deformation, etc.

2. Formula Application: The profile size calculation formula must comprehensively consider factors such as tensile force and straightening.

3. Special Treatment: For thin-walled or complex profiles, the dimensions need to be appropriately increased, considering elastic deformation and overall bending.

4. Adjusting Metal Flow Rate：

1. Fixed Diameter Design: Short fixed diameter sections for thin-walled and complex areas; thick-walled or near-center areas utilize obstruction angles to slow down the flow rate.

2. Auxiliary Structures: Flow promotion angles and material guiding cones accelerate flow; process balance holes, allowances, or flow guiding molds adjust flow rate.

5. Ensuring Mould Strength：

1. Structural Design: Arrange the mold holes reasonably and choose high-strength mold materials.

2. Strength Verification: Verify shear and bending strength for flat molds; for tongue-type molds and flat shunt molds, verify shear, bending, compressive, and tensile strength.

3. Calculation Method: Calculate extrusion pressure using modified Berrylin formula, upper bound method, or empirical coefficient method.

6. Other Key Points：

1. Working Band Size: Consider wall thickness differences, distance from center, and shunt bridge coverage; the working band at thin wall areas should be twice the wall thickness, and appropriate thickening at thick wall areas.

2. Hollow Tool Structure for Mold Holes: Wall thickness >2mm uses straight hollow tools; <2mm uses slant hollow tools.

3. Special Structural Design: For instance, the "mold within a mold" structure addresses the supply balance issue of multiple mold cores, reducing processing difficulty.