Be feom aluminum deep processing
When aluminum profile manufacturers produce aluminum profiles, there are many processes: melting, extrusion, stretching, straightening, cutting and so on. Every process needs to comply with some regulations and matters needing attention. So, what are the precautions in the process of aluminum profile drawing? Let’s take a look.
Before formal stretching, start-up test should be conducted to confirm whether the predetermined stretching rate and clamping method are appropriate. Check whether the conveyor belt, cooling bed and storage table are damaged, and ensure that the table top is clean and free of sundries.
1. First of all, of course, it is necessary to see whether the aluminum profile has obvious distortion in appearance and shape, whether the lower surface is smooth and smooth, and whether there are cracks or bubbles, scratches, burrs and other uneven places. If found, it is best not to buy it, which is the most obvious quality problem.
2.Secondly, it is necessary to carefully check the surface color of aluminum profiles and whether there is color difference. Color difference means that the quality is not enough. Or you can put the profiles of the same model together for comparison. If the color difference is too obvious, it is best not to buy them. In addition, check whether the section thickness of aluminum profile is the same as the marked model, and whether there is any discrepancy between the material object and the marked one.
3.Stretching must be carried out only when the aluminum alloy profile is cooled below 50℃. If the temperature is too high, stretching will not only burn the human body and wool tops, but also show absolute waste products such as twists and turns, twisting, dysfunction and so on before and after aging because the internal stress of aluminum alloy profile cannot be completely eliminated.
4.The control of stretching amount is around 1%, and it should be noted that if the stretching amount is too high, there will be head-to-tail dimension errors, water-streaked twist marks on the outer surface, low elongation, high hardness and brittleness (low plasticity). Too low tension will make the compressive strength and hardness of the profile low, and even aging (quenching) can’t improve the hardness, and the profile is easy to bend in arc (commonly known as broadsword bending).
5.In order to control the tensile deformation and the dimensional change of the whole profile, it is necessary to select appropriate special clamping pads and appropriate methods. Especially for opening material, circular arc material, cantilever material, and zigzag profile, we should pay more attention to the reasonable and useful use of stretching clamp pad.
6.Pay attention to the stress conditions of small feet, thin teeth, long legs, circular arc surfaces, inclined surfaces, openings, viewpoints, etc. of profiles with high width-thickness ratio, long overhanging wall, large radian, wide wall thickness and strange shape, so as to avoid the defects such as deformation, twisting, spiraling and the like of the profiles in part or point scale.
7.Because wool tops have the effect of heat resistance, aluminum profiles with high decorative appearance must be turned up and down, back and forth, so as to facilitate uniform heat dissipation and reduce the transverse bright spot defect caused by uneven heat dissipation and different crystallinity, especially aluminum profiles with large width and thick wall.
8.No rubbing, pulling, stacking, congestion or entanglement with each other shall be allowed in the process of picking, moving and stretching, and a certain interval shall be reserved between each other. The aluminum alloy profiles with easy twists and turns and discharge length should be disposed in time, and if necessary, they should be maintained and disposed of each other.