1. Some unscrupulous merchants will make small moves on profiles in order to maximize profits. Merchants will stick a layer of film on the surface of the profile to identify its brand. However, in order to achieve the purpose of shoddy, some merchants tear up the original film of the profile with poor quality and put on new coats. They follow this method to show their excellent quality. However, the protective film on the surface of the original profile is directly pasted by the manufacturer with scientific methods when leaving the factory, which is characterized by smoothness, flatness and no bubbles and drums, while the manual pasting has bubbles and drums and is uneven.

second, the plastic-steel profile is a hard PVC-polyethylene profile, and its appearance color should be white and blue. The plastic-steel profile with excellent quality has anti-aging characteristics, while the profile with unsatisfactory quality is yellow or white in white. This product is weak in aging resistance, easy to deform and produce serious color difference after a long time. In addition to paying attention to the protective film during acceptance, we must also observe its color. Three, plastic doors and windows should be embedded with special steel lining, the role of steel lining is to fix the door and window structure, not deformation, collapse. Popular point is safety. Excellent plastic-steel products should not only look at their color, but also look at their shape. The thickness and material of steel lining must be determined. Four, according to the national industry standard, the section thickness of the profile must be 2.2 mm.. The section thickness of excellent profiles is generally 2.3 ~ 2.5 mm.