Double layer roll forming machine, that mainly produce different types of colored steel roofing sheet. it is very common in our daily lives. You can see that they are used in various fields, such as Suitable for industrial and civil buildings, warehouses, special buildings, large span steel structure of the roof, wall and interior and exterior decoration, then why is it so widely used? Compared with traditional tiles, it has many advantages, such as light weight, high strength, heat insulation, easy installation, bright colors and waterproof, but at the same time it also has some small defects, such as sound insulation because of its thin thickness. The effect is relatively poor, and the ability to resist wind and cold is relatively poor, and it is easy to rust after a long period of rain and it is not easy to recycle.