In order to reduce the cost, some bad businesses will produce unqualified products during the processing of industrial aluminum profiles. In many cases, we can’t see it with the naked eye, but how can we know where the aluminum profile is defective and leads to disqualification?
1、 The chemical composition is unqualified.
The aluminum profile extruded from aluminum bars doped with a lot of waste aluminum bars has impurities exceeding the standard, and its iron content will be high, so the aluminum will appear black and dark, not shiny, and its hardness is not up to standard. The hardness standard of aluminum profile is 8-12HW. Aluminum profiles like this cannot meet this hardness requirement. We can use a hardness tester for testing.
2、 The film thickness is unacceptable.
In order to reduce the cost of electricity charges and reduce the oxidation time, some businesses lead to unqualified oxide film thickness, which affects the corrosion resistance of cnc milling aluminum industrial profile . Normal film thickness shall not be less than 10 μ。 Also, the sealing time is not enough, and poor sealing will also affect the corrosion resistance and pollution resistance of aluminum profiles. The thickness gauge or salt spray test can be used to check the corrosion resistance of the film thickness. If the hole sealing is not good, a ballpoint pen can be used to draw a line on the surface of industrial aluminum profiles. If it is not easy to clean, it indicates that the hole sealing is not good.
3、 The wall thickness is unacceptable.
The processing price of industrial aluminum profiles in some businesses is calculated by meters, so the thinner the wall thickness is, the lower the cost is. The wall thickness of qualified industrial aluminum profiles is strictly controlled according to the drawings, and cannot exceed the tolerance range. Calipers can be used to measure the wall thickness of unqualified aluminum profiles.
4、 The geometric tolerance is unqualified.
In case of this problem, the technical level of the manufacturer needs to be improved, which may be due to the aging of the extruder, unreasonable mold design, and nonconforming extrusion ratio. The out of tolerance of form and position will lead to the insecure fitting of industrial aluminum profiles and parts, or even the inability to use. We can also use calipers to measure the geometric tolerance, and we should strictly inspect the special dimensions.