Characteristics of stainless steel cold-rolled production and processing

In addition to the cold rolling process, the production process of cold-rolled stainless steel strip also includes other complicated processes. Before cold-rolling the plate, operations such as annealing, pickling and grinding must be carried out. After cold-rolling, it is also necessary to carry out processing procedures such as leveling, straightening, shearing, and stacking. Therefore, the entire cold-rolling process is actually stainless steel. The whole process of coil from hot rolling to cold rolling finished product.

Cold rolled stainless steel coil
Because the performance characteristics and application requirements of stainless steel materials are different, the cold rolling production process has the following characteristics.
Using a multi-roll mill
First of all, as a kind of high alloy steel, stainless steel has high rolling deformation resistance. In order to ensure high efficiency and high precision of rolling, it is best to use a rigid rolling mill, usually a multi-roll cold rolling mill.
Welding is essential
Secondly, when the stainless steel strip is cold rolled on the reversing rolling mill, the head and tail parts wound on the coiler will be cut off and directly become waste because they cannot be pressed down. In order to avoid this situation and increase the yield, both ends of the stainless steel strip should be welded and led before rolling; in addition, if the weight of the hot-rolled stainless steel coil is too small, in order to improve the rolling efficiency and yield, the stainless steel coil should be Pre-coil welding; on the continuous annealing and pickling unit, because it is a continuous operation, the head and tail connections of the stainless steel strip should also be pre-welded. Because welding is essential in the production of stainless steel. However, the welding of stainless steel is different from ordinary steel, and it is much more difficult than ordinary steel; especially, some welds have to be pressed down, and the requirements for welding quality are much higher. Therefore, a suitable welding process is also a feature in the production process of stainless steel cold-rolled strip.
Annealing process
In the production of stainless steel strips, hot-rolled coils need annealing, intermediate annealing is required during cold-rolling, and final products also need annealing, so annealing is also an important part of cold-rolled coil production. And because there are many stainless steel specifications and their properties are different, the purpose, method and requirements of heat treatment must be considered.
Take measures to eliminate and prevent defects
Cold-rolled stainless steel is a kind of high-grade steel, and its surface quality requirements are very strict. It can neither retain the smelting defects caused by the previous process nor show obvious defects in the cold-rolling process. Therefore, various elimination and protection measures must be used in production. For example, in order to eliminate the hot-rolled iron oxide scale, the hot-rolled strip needs shot peening and pickling; in order to eliminate the defects caused by the billet and the defects caused by cold rolling and heat treatment, the stainless steel strip is usually ground on the grinding unit; In order to ensure the surface quality of stainless steel after cold rolling, there are very strict requirements on the grinding of the rolls. In general, the production process of cold-rolled stainless steel is far more meticulous than other steels.
Finishing
The finishing process of stainless steel is also different from that of ordinary steel. The flattening process not only needs to optimize the shape of the plate, but also uses a roll with a high degree of finish, so that a smooth 2B panel can be produced. To improve the formability of stainless steel sheets, this is essentially a quench and temper rolling. Because stainless steel has a hard texture and strict flatness requirements, it must be straightened with a strong straightening machine, and products with different thicknesses usually use different straightening methods. Stainless steel cold-rolled products are generally delivered in two ways: coiled and cut, and sometimes delivered in strips. Therefore, modern stainless steel cold rolling mills need to set up slitting and cross-cutting units respectively.