A good set of molds, besides ensuring the machining of mold components, must also have proper assembly work. If adjustments are not done correctly during assembly, it can result in uneven gaps between the punches, accelerate mold wear, and produce defective products. There is no specific standard for the maximum number of uses of aluminum extrusion molds, but the following points can generally be referred to:
1) The quality of the steel used for the dies,
2) The design of the extrusion dies and die manufacturing technology,
3) Whether the maintenance of the extrusion dies is adequate,
4) Whether the aluminum profile extrusion production process technology is reliable,
5) Whether the management of the extrusion dies is proper.
If all five of these points are optimized, an aluminum extrusion die can be used for over a million cycles without any problem. These five requirements are not only related to the die's lifespan, but they also need to be addressed sequentially from 1) to 5) to ensure each aspect is properly linked.
Designing mold structure to determine the number of uses and lifespan of the mold
(1) The overall mold inevitably has concave fillets. When the fillet radius is less than 2 mm, or in deep and narrow concave mold cavities, or when concave fillets have tool marks after machining, stress concentration is easily caused, which can lead to cracking.
(2) Within the tolerance range of the blank, in order to reduce the ejection force and shorten the time the blank remains in the mold cavity, the mold is given an appropriate draft. For example, in bell-shaped shell products, the upper end of the head section with the same diameter is about 0.1 mm larger than the lower end. For the rod section with the same diameter, the upper end is approximately 0.4 mm larger than the lower end. This reduces the ejection force and minimizes scratches on the concave mold cavity surface. Reverse draft, or undercut, is strictly prohibited, as it reduces the blank quality, shortens the mold life, and can even cause cold shut, leading to mold damage.
(3) The mold's guiding device is also very important. It ensures the relative positional accuracy of mold components during operation, prevents uneven mold wear, and a reliable guide structure helps avoid damage between the male and female dies. It is especially important for molds with small clearances. Otherwise, uneven load can cause premature mold failure.
(4) Using reasonable clearance between male and female molds not only effectively improves product quality but also affects mold longevity. If the clearance is too small, it can cause die biting; if too large, it affects product coaxiality and may cause bending of the male mold due to uneven load, reducing the male mold's service life.
(5) The machining accuracy of the mold depends on the final polishing process in mold manufacturing. The quality of polishing not only directly impacts the mold's service life but also affects the surface finish and dimensional accuracy of the finished product.
(6) Reasonable assembly, debugging, and management.
