In the production process of cold-rolled stainless steel plate, in addition to annealing, pickling and grinding before cold-rolling, but also stainless steel processing such as leveling, straightening, shearing, and stacking after cold-rolling, so the whole process is essentially The above is the whole process from the hot-rolled coil to the production of the cold-rolled finished product.
Because of the characteristics of stainless steel materials and the special requirements for quality, the characteristics of the cold rolling process are also obvious.
First: as a kind of high alloy steel, stainless steel has strong resistance to rolling deformation. In order to perform high-efficiency and high-precision rolling, it is necessary to use a rolling mill with greater rigidity, usually a multi-roll cold rolling mill.
Second: When the stainless steel strip is cold rolled on the reversing rolling mill, the head and tail parts wound on the coiler cannot be pressed down and are cut off and become waste products. In order to improve this situation and increase the yield of stainless steel, 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 light, in order to enhance the rolling efficiency and yield, the stainless steel coil is also Welding should be done in advance; on the continuous annealing and pickling unit, because of the continuous operation, the head and tail connections of the stainless steel strip should also be welded. Therefore, welding is an indispensable link in stainless steel production. However, the welding of stainless steel is different from ordinary steel, and the welding is more difficult, especially some welds are under pressure, and the requirements for welding quality are also stricter. Therefore, the special welding process is also a feature of stainless steel cold-rolled strip production.
Third: In the process of stainless steel production, the hot-rolled coil as the raw material needs to be annealed, the cold-rolled process needs to be subjected to intermediate annealing, and the final product is also annealed. Annealing is an important link in production. And there are many types of stainless steel, and the properties of various stainless steel materials are also different. The purpose, method and requirements of heat treatment are different, and these have their own unique processing technology.
As a high-grade steel product, cold-rolled stainless steel has very strict requirements on surface quality. Not only the metallurgical defects caused by the previous process are not allowed to remain, but also significant defects caused by the cold-rolling process are not allowed. Therefore, a series of elimination and protection measures are used in the production process.
For example, in order to remove the hot-rolled iron oxide scale, the hot-rolled strip needs to be shot peened and pickled; in order to remove the defects caused by the billet and the defects caused by cold rolling and heat treatment, the stainless steel strip is usually ground on a grinding unit; In order to ensure the surface quality of stainless steel after cold rolling, there are high requirements for the grinding of the rolls; in order to avoid scratches in the production process, the stainless steel coils of each unit are required to be tightly rolled and rolled, and cold rolling is performed. In many units before and after the coil, craft paper should be placed on the interlayer of the stainless steel coil; in addition, some special protective measures are also used on the operations and equipment that are prone to scratches; in order to obtain better and uniform surface gloss , the finished product needs to be pickled after annealing, and the bright plate with special requirements needs to be annealed in a protective atmosphere; in order to protect the surface of the stainless steel product, sometimes the surface of the finished product needs to be coated. In general, the production of cold-rolled stainless steel is a meticulous processing process, which is incomparable with other stainless steels.
In simple terms, the finishing of stainless steel is also different from ordinary steel. There are some special requirements. For example, the flattening process should not only improve the shape of the plate, but also use rollers with high smoothness to produce a smooth 2B stainless steel surface. Ferritic stainless steel also optimizes the forming performance of stainless steel by controlling the amount of flat reduction, which is essentially a kind of quenching and tempering rolling. Because stainless steel is harder, it also has higher requirements for flatness. It must be straightened with a strong straightening machine, and products with different thicknesses usually use different straightening methods.
Hunan Centeway has been specializing in the production of stainless steel coils for more than 20 years. For any needs, please contact
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