The lifespan of aluminum extrusion molds has become a major bottleneck in the development of China's aluminum profile industry. The design and manufacturing costs of aluminum extrusion molds account for about 20% of the total production cost, making it one of the key technologies in the aluminum extrusion industry, which is characterized by high variability and rapid development. It involves many aspects such as materials, design, manufacturing, testing, mold repair, and management, and is also one of the areas with considerable development potential.
How can we use this type of diversion mold more efficiently? We can approach it from the following aspects.
(1) Strictly implement the production process regulations for aluminum profiles
It is necessary to strictly follow the corresponding aluminum profile extrusion process. During startup, the temperature in the middle section of the aluminum rod furnace should be set at 530-550°C, and the temperature at the outlet section should be set at 480-500°C. The insulation time must be sufficient to ensure that the aluminum rods are adequately heated throughout (i.e., both the core and the surface are sufficiently heated). This prevents uneven temperatures between the surface and the core, which could increase elastic deformation of the die, thereby aggravating the occurrence of "uneven walls" and "inconsistent lengths," and could even lead to plastic deformation of the extrusion die and its scrap.
(2) Ensure 'Three Centers in One'
The centers of the extrusion barrel, the extrusion rod, and the die must be visually concentric. Any obvious eccentricity is not allowed, as it can affect the flow rate in different parts of the product, potentially impact product forming, or cause the two sides of the extruded product to differ in length to the point that extrusion production becomes impossible.
Mold Damage Inspection
① The material chosen for the manufacture of molding mold components does not meet the requirements of the working conditions, causing the mold to deform, corrode, or wear severely after working for a period of time.
② When installing or removing components of the molding mold, hammering the parts can cause the mold components to deform, damage the finished surfaces, or leave impact marks on the working surfaces.
③ If the flow divider cone angle is too large, it increases the resistance to molten material flow, causing the support ribs of the flow divider cone to break.
④ Low hardness of the working surfaces of the die or mandrel can lead to severe wear on the finished surfaces, resulting in rough surfaces.
⑤ Incorrect mold adjustment can cause the mold adjustment screws to break or deform the die or sizing sleeve, rendering them unusable.
(3) Proper selection of support pads
It is essential to choose appropriately sized double-hole specialized support pads to reduce the elastic deformation of the lower mold, ensuring stable forming of the extrusion products with minimal dimensional variation. Additionally, the double-hole specialized support pads must be prepared in advance before the mold is taken out of the furnace to prevent excessive cooling of the mold due to time spent searching for support pads, which could lead to a stuck mold.
4) Strengthen information feedback during the aluminum profile extrusion process
A: Information feedback on die plugging
There are many reasons for die plugging, and people without specialized training generally find it difficult to explain clearly. It is best for the relevant mold repair personnel to personally inspect and identify the cause before attempting to rework the die.
B: Feedback on Extrusion Molding
In addition to having the extrusion die number clearly marked on the billet, the overall flow direction of the billet, which is difficult to discern, must also be indicated on it. For example: a. 'Converging extrusion' (indicating that during actual extrusion, the inside of the two holes moves slower than the outside); b. 'Diverging extrusion' (indicating that during actual extrusion, the inside of the two holes moves faster than the outside); c. 'Left long, right short' indicates the left branch is longer and the right branch is shorter. It is also necessary to specify the difference in length because the distance from the cutoff saw to the extrusion outlet is about 6 meters. Usually, the format 'A meters / 6 meters' is used to indicate that every 6 meters, there is a difference of A meters. Such a detailed and accurate expression helps the die repair personnel make correct judgments and perform maintenance.
C: Feedback on Excessive Dimensional Deviations:
When encountering a situation where the extrusion molding is normal but the dimensions are off, it is essential to take a sample and properly mark it with complete and accurate information (extrusion mold number, extrusion direction, dimensional defects, etc.). Any incorrect marking can lead to repairing the wrong mold, so great care must be taken.
Only with such complete feedback on usage can maintenance personnel make correct judgments and repairs, improve mold maintenance efficiency, and reduce the number of repairs and unnecessary trial moldings.
