1. The surface of the aluminum ingot is attached with debris or the composition of the aluminum ingot is segregated. When there are a large number of segregated floats on the surface of the aluminum ingot and the aluminum ingot has not been homogenized or the homogenization treatment effect is not good, there are a certain number of hard metal particles in the aluminum ingot. During the extrusion profiles process, when the metal flows through the working belt, these segregation floats or hard metal particles adhere to the surface of the working belt or cause damage to the working belt, and eventually scratch the surface of the profile;
2. There are sundries on the mold cavity or working belt, and the hardness of the working belt is low, so that the surface of the working belt is injured during extrusion and scratches the profile;
3. There is bare metal or hard inclusions on the discharge track or swing bed, which will scratch the surface of the profile when it is in contact with the profile;
4. When the fork bar sends the aluminum profiles from the discharge track to the swing bed, the profile is bruised due to the excessive speed;
5. Manually drag the profile on the swing bed to cause scratches;
6. During transportation, the profiles are damaged by friction or extrusion
Solution
1. Strengthen the quality control of aluminum ingots;
2. Improve the quality of mold repair, the mold is regularly nitrided and the nitriding process is strictly implemented;
3. Use soft felt to isolate the profile from the auxiliary equipment to minimize the contact damage between the profile and the auxiliary equipment;
4. It should be handled with care during production, and try to avoid dragging or flipping the profiles at will;
5. Arrange the profiles reasonably in the material frame and try to avoid mutual friction.
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