Carbon steel plate is a kind of material with a large amount of use, which is divided into ordinary low carbon steel plate and special steel plate, including low alloy high strength steel and corrosion and heat resistant clad steel plate. Ordinary low-carbon steel sheets are divided into two types: cold-rolled and hot-rolled. Cold-rolled steel sheets have good surface quality and precise thickness and dimensions, and are mostly used in the manufacture of car bodies. Hot-rolled sheets are mostly used in the manufacture of frames and the like.