The production of cold-rolled stainless steel strips is not a simple "cold rolling" process. Typical production processes of cold-rolled stainless steel strips also include: heat treatment, pickling, grinding, etc. of hot-rolled steel strips; flattening; cross-cutting into steel plates or longitudinal cutting. Steel strip; sorting; cleaning and packaging.
Cold rolled stainless steel strip production process characteristics
Due to the characteristics of stainless steel and the special requirements for product quality, the stainless steel cold rolling production process has the following characteristics:
(1) Stainless steel is a high-alloy steel with greater resistance to rolling deformation. In order to carry out high-efficiency and high-precision rolling, a rolling mill with high rigidity should be used, usually a multi-roll cold rolling mill.
(2) Multi-roll cold rolling mills generally adopt a single-machine reversible rolling method. The head and tail parts wound around the coiler during rolling cannot be rolled and are cut off to become waste products. In order to improve the yield of the product, a section of lead tape must be welded at both ends of the stainless steel strip before rolling, and the lead tape part is not rolled; in addition, if the quality of the hot-rolled coil is too small, in order to improve the rolling efficiency and yield; it is necessary to Small steel coils are welded together into large steel coils in advance; in the continuous annealing and pickling units, due to continuous operation, the head and tail connections of the steel strips also need to be welded. Therefore, welding is an indispensable link in the production of stainless steel strips. The welding of stainless steel is much more difficult than the welding of ordinary steel. Especially when the weld needs to be rolled, the requirements for welding quality are more stringent. Therefore, special welding processes are also a feature of cold rolling production of stainless steel strips.
(3) Before cold rolling of stainless steel strips, the raw materials (hot rolled coils) must be annealed, intermediate annealing is required during the cold rolling process, and the final product must be annealed as finished product, so annealing is an important link in production. There are many types of stainless steel, each type of steel has different properties, the purpose, method and requirements of heat treatment are all different, and there is a unique process system.
(4) The requirements for surface quality of cold-rolled stainless steel strips are very strict. Not only the metallurgical defects and processing defects caused by the previous process are not allowed to remain, but also the obvious defects caused by the cold rolling process are not allowed. To this end, a series of elimination and protection measures have been taken during the cold rolling production process. For example: in order to eliminate the oxide scale in hot rolling, the hot-rolled steel strip needs to be shot blasted and pickled; in order to eliminate the defects caused by the billet and the defects caused by cold rolling and heat treatment, the steel strip often needs to be repaired on the grinding unit. Grinding; in order to ensure the surface quality after cold rolling, there are very strict requirements for the grinding of the rolls. In order to prevent the steel strip from being scratched during the production process, the steel coils of each unit are required to be tightly rolled and evenly rolled, and before and after cold rolling Many units must put protective paper between the layers of steel coils when coiling; in addition, some special protective measures are also taken on operations and equipment that are prone to scratches; in order to obtain a good and uniform surface gloss, there are The finished products must be pickled after annealing; bright steel plates with special requirements must be annealed in a protective atmosphere; the surface of some products must be coated with film, etc. In short, the production of cold-rolled stainless steel strips is a meticulous process that is unmatched by other steel types.
(5) There are some special requirements for the finishing of stainless steel strips. For example, the flattening process must not only improve the plate shape, but also use rolls with very low roughness (except for hemp panels) to produce bright 2B steel pans. For ferritic stainless steel, the forming performance of the steel plate must be improved by controlling the flattening amount. Stainless steel is hard and has strict requirements on straightness, so it must be straightened with a powerful straightener, and products of different thicknesses often require different straightening methods; stainless steel cold-rolled products are usually produced in two forms: coiling and cutting. Therefore, modern stainless steel cold rolling mills are equipped with slitting units and cross-cutting units respectively.
GNEE Steel Co., Ltd. is a manufacturer of cold rolled steel products. It is located in Anyang, China's largest steel product production base and distribution center, and also close to Tianjin. We have many loyal customers in Europe, South America, the Middle East, Asia and other places. We have a wide range of steel products such as stainless steel, galvanized steel, cold rolled steel, carbon steel, alloy steel, etc. The annual export volume is approximately 1 million tons.
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