hot rolling takes slab (mainly continuous casting slab) as raw material and is made into strip steel by roughing mill and finishing mill after heating. The hot steel strip from the last finishing mill is cooled to the set temperature through laminar flow, and then rolled into steel strip roll by coiler. The cooled steel strip roll is processed into steel plate, flat roll and longitudinal cut steel strip products through different finishing operation lines (leveling, straightening, cross cutting or longitudinal cutting, inspection, weighing, packaging and marking, etc.) according to the different needs of users. To put it simply, after heating (that is, the red and hot steel block in TV), a billet is refined for several passes of rolling, then trimmed and corrected into a steel plate. This is called hot rolling
> the hardness of the cold rolled coil can only be deteriorated due to the hardness of the cold rolled coil, which can only be used as the raw material for cold rolling. Br>> after cold rolling, the hardness of the cold rolled coil is deteriorated. The hard rolled coil can be used as the raw material of the hot-dip galvanizing plant, because the hot-dip galvanizing units are equipped with annealing lines. The weight of rolled hard coil is generally 6 ~ 13.5 tons. The hot-rolled pickling coil is continuously rolled at room temperature. The inner diameter is 610mm
product features: because it has not been annealed, its hardness is very high (HRB is greater than 90) and its machining performance is very poor. It can only carry out simple directional bending less than 90 degrees (perpendicular to the coiling direction)
to put it simply, cold rolling is processed and rolled on the basis of hot rolled coils. Generally speaking, it is a processing process of hot rolling pickling cold rolling
cold rolling is processed from hot-rolled plate at normal temperature. Although the steel plate will be heated due to rolling in the processing process, it is still called cold rolling. The cold rolling, which is formed by continuous cold deformation after hot rolling, has poor mechanical properties and high hardness. Only after annealing can its mechanical properties be restored. Those without annealing are called rolled hard coil. Rolled hard coil is generally used to make products without bending and stretching. It is rolled hard with a thickness of less than 1.0 and bent on both or four sides with good luck
1. Cold rolling is processed from hot rolled plate at room temperature
2 After heating (that is, the red and hot steel block in TV), a billet is refined for several passes of rolling, then trimmed and corrected into a steel plate. This is called hot rolling.
in short, hot rolling can be understood as rough rolling and cold rolling can be understood as finish rolling
the surface of cold-rolled sheet has a certain gloss. It feels smooth by hand, which is similar to the common steel water cup used to drink water. Cold rolling is processed from hot rolled plate at room temperature
if the hot-rolled plate is not pickled, it is similar to the surface of many ordinary steel plates in the market. The rusted surface is red and the non rusted surface is purple black (iron oxide scale)
after heating (that is, the red and hot steel block in TV), a billet is refined for several passes of rolling, then trimmed and corrected into a steel plate. This is called hot rolling.