1.Crude stainless steel smelting process: At present, the smelting process for producing stainless steel in the world is mainly divided into one-step method, two-step method and three-step method, as well as new integrated production methods. The one-step smelting method is: molten iron + AOD; the two-step method is: EAF + AOD. The three-step method is: EAF+AOD+ VOD. In addition to several traditional production processes, the current integrated production process, that is, the production process from molten iron directly to stainless steel, has also been adopted by many companies. The production process is:RKEF+AOD.
2. Stainless steel hot rolling process: The stainless steel hot rolling process uses slabs (mainly continuous casting billets) as raw materials, and after heating, the rough rolling mill and the finishing mill are used to make strip steel. The hot steel strip from the last rolling mill of finishing rolling is cooled to the set temperature by laminar flow, and then coiled into steel coil by the coiler. The cooled steel coil has oxide scale on the surface and appears black, commonly known as “stainless steel black coil” . After annealing and pickling to remove the oxidized surface, it is called “stainless steel white skin coil”. Most of the hot-rolled products circulating in the stainless steel market are stainless steel white skin coils.
Stainless steel cold rolling process: After the stainless steel is hot rolled, part of the stainless steel hot-rolled products are directly used downstream, and some hot-rolled products need to be processed into cold-rolled before use. For stainless steel cold rolling, hot-rolled stainless steel products with a thickness of 3.0-5.5mm are mostly used. After rolling by cold-rolling equipment, they are produced into stainless steel cold-rolled products. At present, the main production processes of stainless steel cold rolling are two types: stainless steel single-stand cold rolling and stainless steel multi-stand cold rolling.
After the stainless steel is cold rolled, it needs to go through an annealing and pickling line. Annealing of stainless steel after cold rolling is to eliminate work hardening through the recrystallization process to achieve softening; the purpose of pickling is to remove the oxide layer formed on the surface of the steel strip during the annealing process, and the second is to passivate the surface of the stainless steel. , Improve the corrosion resistance of steel plate.