hot rolled coils

Standard Code: GB / T 709-2006
Standard Name: hot-rolled steel sheet and strip size, shape, weight and allowable deviation
Standard Status: Current
The implementation date :2007-2-1
Promulgation of Department: State Administration of Quality Supervision, Inspection and Quarantine and the Standardization Administration of China
Brief Introduction: This standard specifies the size of hot-rolled steel sheet and strip, shape, weight, and technological conditions. This standard applies to rolling width of not less than 600mm of rolled sheet, strip and the shear plate and the longitudinal strips.
Standard Code: GB 11251-1989
Standard Name: Alloy structural steel hot-rolled steel plate
Standard Status: Current
The implementation date :1990-1-1
Promulgation of Department: Bureau of Technical Supervision
Brief Introduction: This standard specifies the structure of the alloy steel hot-rolled steel plate of the size, shape, technical requirements, test methods, inspection rules, packaging, marking and quality certificates. This standard applies to more than 4 ~ 30mm thickness of the alloy steel hot-rolled steel plate.

Hot-rolled plate hardness is low, is easily processed, ductility can be good.
Cold-rolled sheet, high hardness, relatively difficult to process some, but not easy to deformation, a higher intensity.
Relatively low strength of hot-rolled plates, surface quality and almost (with oxidation \ finish low), but the plastic is good, generally plate, cold-rolled sheet: high intensity, \ high hardness, high surface finish, generally plate, can serve as a punching with the board.
Hot-rolled steel, mechanical properties far and cold, but also inferior to forging, but there are good toughness and ductility
Cold-rolled steel sheet due to a certain degree of work-hardening, toughness is low, but it can achieve a good yield ratio, is used to cold-formed parts such as leaf spring, and because relatively close to the tensile yield point, so there is no risk of the use during the course of predictability, in the load is larger than the allowable loads are susceptible to accidents
Added cold-rolled steel 0.3-3.0mm, hot-rolled steel sheet 2.0

About hot-rolled steel plate with the beginning of rolling slab continuous casting slab or as raw material, after reheating furnace heating, high-pressure water descaling entered the rough mill, roughing cut is expected by the head, tail, re-entering the finishing mill, the implementation of the computer controlled rolling, and finally after rolling through the laminar cooling (computer-controlled cooling rate) and the winding machine winding, becoming straight hair volume. Straight hair volume head, tail and tongue are often presented fishtail shape, thickness, width less accuracy, often there is wave-shaped edge, hem, tower and other defects. Heavier weight of its volume, coil inner diameter of 760mm. (Generally prefer to use the pipe industry.) Will roll through the straight hair cut head, cut tail, cutting edge and multi-pass straightening, leveling and other finishing line treatment, and then cutting board or heavy volume, it becomes: hot-rolled steel plate, flat hot-rolled coil, slitting with other products. Hot roll finishing, if removal of oxide by pickling and oiling after the branding for pickling hot-rolled coils. The alternative to cold-rolled sheet products are part of the trend, the price is moderate, well received by customers love.

About hot-rolled steel plate with the beginning of rolling slab continuous casting slab or as raw materials