The thickness of cold-rolled steel plates on the market generally does not exceed 6mm. On the one hand, it is subject to market demand, and on the other hand, it is also limited by the rolling process. Cold-rolled steel plates are made by cold rolling, annealing, and pickling of hot-rolled steel coils. Their plasticity decreases and their hardness increases. Therefore, after exceeding a certain thickness, its surface state cannot meet the surface quality requirements of cold-rolled steel plates.
Thickness specifications of stainless steel cold-rolled plates:
Thickness is generally ≤6mm and width is generally ≤1.5m.
The maximum thickness of cold-rolled steel plates is 8mm, and the widest is 2m. (Note: The above data refer to stainless steel materials)

1. In terms of color, black pipe is black as its name suggests; while galvanized pipe is a silvery white or gray pipe, which will appear this color after being plated with zinc.
2. The materials used are also different. Black pipes are usually made of cold-rolled or hot-rolled plates; while galvanized pipes are made of cold-rolled plates that have been galvanized. Since galvanized pipes are coated with zinc on the surface, they can effectively prevent corrosion and rust, so they can be used in a wider range of applications.
Although black pipes and galvanized pipes are both pipes, the price of black pipes is relatively low, which has cost advantages; while the price of galvanized pipes is higher, compared with other similar products, they have a longer service life and a more appropriate cost.

1. The main difference between the two is the degree of their coating. The galvanized steel sheet is mainly plated with zinc on the coating. The coating of the galvalume steel sheet is not only zinc but also aluminum.
2. The surface of the galvanized steel sheet is plated with zinc, which has a good protective effect on the material and is not easy to rust. As for the galvalume steel sheet, because part of the zinc on the surface is changed to aluminum, it is easy to oxidize and rust. So in comparison, the service life of the galvanized steel sheet is longer than that of the galvalume steel sheet.