First, the hot-rolled steel profiles will roll straight hair by cutting head, cut tail, trimming and multi-pass straightening, leveling and so after finishing line, then cutting board or heavy volume, that is to be: hot rolled steel plate, flat hot rolled coils, slitting and other products. If the finishing hot roll pickled to remove oxide and coated with oil Serve hot rolled pickled coils. The alternative to cold-rolled sheet products are the trend of local, affordable, loved by the majority of users. Second, the types and uses of hot-rolled steel plate [1] 1, structural steel production of general structural steel and welding structural steel, mainly used for steel structure, bridge, ship, vehicle production. 2, the weathering steel to add a special element (P, Cu, C, etc.), has good corrosion resistance and resistance to atmospheric corrosion, for the container, the production of special vehicles, but also for building structures. 3, vehicle structural steel has good welding properties DRAWING performance and high-strength steel for the automotive FRAME, WHEEL, and other production. 4, the general mechanical structure of hot-rolled special steel, carbon steel, alloy steel, tool steel, after heat treatment works for a variety of mechanical parts production. 5, the original plates for the production of cold-rolled cold-rolled products, including CR, GI, color-coated and so on. 6, steel pipe steel has good processing properties and compressive strength, volume 500 for the production of content!? Less filling LPG, acetylene gas and a variety of high-pressure gas pressure gas container. 7, pressure vessel steel plate has good processing properties and compressive strength, volume 500 for the production of content!? Less filling LPG, acetylene gas and a variety of high-pressure gas pressure gas container. Third, the difference between hot-rolled steel and cold rolled steel hot rolled plate of low hardness, easily processed, good ductility. Cold rolled sheet, high hardness, relatively difficult to process some, but not easy to deformation, high strength. Relatively low strength of hot-rolled plates, surface quality almost (with oxidation \ finish low), but the plastic is good, generally plate, cold rolled sheet: high strength, \ hardness, surface finish, usually thin, can be used as punching with the board. rolled steel, mechanical properties far and cold, but also inferior to forging, but good toughness and ductility cold-rolled steel sheet due to a certain degree of hardening, toughness is low, but it can achieve better yield ratio, used to cold springs and other parts, while the yield point closer to the tensile strength, so the risk of not using the predictability of the process, the load is larger than the allowable load, prone to accidents added, 0.3-3.0mm cold rolled steel plate , hot-rolled steel sheet 2.0