Squeeze the flaw. Whether the extrusion process is complete, whether the extrusion process is mature, and whether the operation is improper or not, will produce defects such as bubbles, inclusions, layers, chromatic aberration and distortion, which affect the quality of aluminum profiles.
Thin oxide film thickness. The national standard stipulates that the thickness of the oxide film of the building aluminum should not be less than 10um (micron). The thickness is not enough, the surface of aluminum profile is easy to rust and corrode. Sampling of some of the no production name, site, production license, certification of aluminum, the thickness of the oxide film is only 2 to 4um, and some even have no oxide film. According to the experts estimated that each reduction of 1um oxide film thickness, each ton of profiles can reduce power consumption costs of more than more than 150 yuan.
The chemical composition is unqualified. It can greatly reduce the cost, but it will lead to the unqualified chemical composition of aluminum alloy, which endangers the construction safety seriously.
Reduce the wall thickness of the profile. 90 Series Push-pull window type, according to national standard its aluminum wall thickness minimum is not less than 1. 4mm, some products only 0. 6 to 0. 7mm. 46 series of ground-bomb door-type, the national standards used in the thickness of the aluminum alloy is not less than 1. 62mm, sampling, some products only 0. 97 to 1. 18mm.
The poor quality aluminum material reduces the sealing time greatly, reduces the chemical reagent loss, the cost is reduced, but the corrosion resistance of the profile is reduced.
Previous: Extrusion principle of aluminum profile