The aluminum alloy extruded profiles used in large radiators are mostly solid. Their characteristics include a large external circular size, complex cross-sectional shapes, significant differences in wall thickness, small fin spacing, and large cantilevers. When the aspect ratio of the same cross-section and the tongue ratio (cantilever length: fin spacing = tongue ratio) and the external circular diameter of the profile exceed a certain range, it becomes difficult to achieve uniform metal flow using flat dies, and the molds are easily damaged. To address these issues, several typical structures of molds have been developed.
High-precision, high-difficulty extruded profiles for electronic high-density fin radiators require special processes and designs to manufacture special molds successfully. The mold material must be high-quality, high-strength, heat-resistant alloy steel, and must undergo forging, pre-treatment, and flaw detection. The hardness of the mold should not be too high, and it should not undergo nitriding treatment. The mold design can use special flow guiding molds, wide expansion molds, and flat combination molds based on its shape and technical requirements, with precise calculations and adjustments for the structure and dimensions of each size and part. For example, the working band, outlet band, wide expansion angle, and flow guiding mold dimensions must all be precisely designed to allocate metal flow and speed accurately. Additionally, during mold making, it is essential to follow the drawings meticulously and ensure tolerances are met. In the production of such radiator profiles, controlling mold repair and extrusion workers is also very important.