1. Air oxide film thickness - - Insufficient thickness, aluminum surface is very easy to rust, erosion. The national industry standard thickness of anodized film for building and industrial aluminum should not be less than 10um (μm). Some features name, detailed address, production license, qualification industrial aluminum profiles, plastic film thickness is 2 to 4um, some or no film.       

        2 kinds of chemical composition, mixed with a lot of waste aluminum, industrial aluminum profile can greatly reduce the cost, but will cause industrial aluminum chemical composition is not pass, more serious serious harm to safety engineering professional.        

        3. Thickness throughout the basic same specifications of engineering drawings, and its cross-sectional specifications, total width, core hole, but the difference in wall thickness is very large, but also can be very different net weight, each price is also corresponding to a very big difference. In addition, the lower industrial aluminum can reduce some of the shutdown time, reduce the cost of chemicals, but the raw material corrosion resistance is greatly reduced.       

        4. Manufacturers -- large and medium-sized aluminum profile factories, raw materials, production process specification, strict quality management, processing fees than small manufacturers, processing fees can be 2000-3000/ ton apart. Smaller 2-3 yuan /kg.