Buy aluminum windows and doors must look at three points:
1. Look at the materials. High-quality aluminum doors and windows with aluminum, thickness, strength and oxide film, should comply with the relevant provisions of national standards, should be 1.2 mm wall thickness, tensile strength reached 157 Newtons per square millimeter, the yield strength to reach every square millimeter 108 Newton, the oxide film thickness should reach 10 microns. If you can not reach the above criteria, indicating that this is the poor quality of aluminum windows and doors, it can not be used.
2. Look processing. High-quality aluminum doors and windows, precision machining, installation stress, good sealing performance, switch freely. Poor quality of aluminum doors and windows, aluminum blind selection series and specifications, processing shoddy, to sawing instead of milling is not required for installation, sealing performance is poor, not only leaking air leakage and the emergence of the phenomenon of glass burst, but encountered strong winds and external forces , easy to push and pull part or glass scraped off or touch down, wounding and breaking things.
3. To look at the price. In general, high-quality aluminum windows and doors because of the high production costs, the price is higher than the low-grade aluminum alloy doors and about 30%. Some of the wall thickness of only 0.6-0.8 mm aluminum doors and windows made of aluminum, tensile strength and yield strength is much lower than the relevant national standards, the use of very safe.