The primary purpose of cold rolling of steels is to reduce the thickness of the hot rolled steel strips (normally ranging from 2 mm to 6 mm) into thinner thicknesses (usually ranging from 0.09 mm to 3.15 mm) for improving the physical and mechanical properties, to make it work for different segments of the market.
Advantages of Cold rolling
Bright annealing is an annealing process performed in a controlled atmosphere containing inert gases (such as hydrogen and nitrogen). This controlled atmosphere reduces the surface oxidation to a minimum which results in a brighter surface and a much thinner oxide layer. Pickling is not needed after bright annealing since the oxidation is minimal. Since there is no pickling, the surface is much smoother which results in better resistance to corrosion.
Annealing is a heat treatment process which alters the microstructure of a material to change its mechanical or electrical properties. Typically, in steels, annealing is used to reduce hardness, increase ductility and help eliminate internal stresses. Annealing is a generic term and may refer to subcritical, intermediate or full annealing in a variety of atmospheres.
Pickling process is used to remove a thin layer of metal off of the stainless steel part. This is different from the descaling process, which removes visibly thick oxide scale from the stainless steel part. Our pickling solutions for stainless steel are mixtures of nitric acid and hydrofluoric acid. Corrosion on the contacted part can occur if the process is not done.
Tension levelling is a process used in the steel industry to remove any shape defects (i.e. out of flatness) present in cold rolled material. It is generally the final process before the cold rolled product is dispatched to the customer, and is therefore a process which plays an important role in delivering the desired material properties and the product standards required by the customerThe tension leveling process is a combination of elongating the strip and bending the fibers over a series of work rolls. Tension leveling will eliminate edge wave & center buckle as well as correct excessive crossbow and coil set
Skin-pass rolling (or temper rolling) is usually the final forming step in the production of cold-rolled steel sheets, following the annealing process. Reduction of 2% - 3% is to improve flatness, produce the final surface finish or texture and develop mechanical properties.
Slitting is a process to cut a wide coil of metal into a number of narrower coils as the main coil is moved through the slitter. During the slitting process, the metal coil passes lengthwise through the slitter's circular blades.
A Cut-To-Length Line will uncoil the material, level it, and then cut it to the required length, the end product produced by a Cut-To-Length Line is a flat sheet of material cut to a very precise length tolerance