Process Comparison Of Annealing And Pickling Line For Cold Rolled Stainless Steel

After cold rolling treatment, the hardness and strength of the stainless steel plate are significantly improved, but the formability is insufficient and it is difficult to put it into the market. Therefore, a series of follow-up treatments should be performed. Among them, the cold-rolled stainless steel annealing and pickling line processes and anneals cold-rolled sheets to remove the stress of the strip, remove the oxide scale formed during processing and annealing, and finally perform finishing and straightening treatments to improve the surface quality of the strip and obtain Satisfied with the product. Therefore, it is of great practical significance to study the process comparison of cold-rolled stainless steel annealing and pickling lines.

Table of Contents Hide
1 Cold rolled stainless steel, annealed and pickled

1.1 Traditional technology

1.2 No nitric acid Pickling

1.3 Dalnox brighttm technology

1.4Comparison of the three: cold rolled stainless steel, annealed and pickled, hot rolled stainless steel strip annealed and pickled
Finally, cold rolling should be carried out to meet the corresponding performance and thickness requirements. During the cold rolling process of stainless steel, work hardening occurs, and as the amount of cold rolling increases, the level of work hardening increases. If the temperature of a work-hardened material is increased to 900-1100°C, the deformation stresses are eliminated and recrystallization occurs at high temperatures, thus softening the material. Annealing after cold rolling can be divided into continuous horizontal annealing and vertical bright annealing according to the annealing method, and intermediate annealing and final annealing according to the annealing process.
Comparison of Cold Rolled Stainless Steel Annealing and Pickling Line Processes Traditional Technology
Traditional cold rolled stainless steel

The annealing and pickling line includes the following aspects:

① The entrance area, which consists of uncoiler, shearer, straightener, etc., and is mainly used for uncoiling.
② Welding machine, usually choose narrow lap seam welding machine, choose seam welding rolling process to carry out welding work.
③ The degreasing section consists of four functional sections, including spray washing section, brush washing section and cleaning section machine drying section one by one. The degreasing medium is mainly alkali solution and hot water in rinsing section, and air knife is selected for drying.
④ Loop, horizontal loop including outlet loop, inlet loop, etc.
⑤ For annealing furnace, the horizontal suspension type gas annealing furnace is usually selected to raise the temperature of steel strip to 1050-1150 ℃, so as to eliminate the work hardening and internal stress formed during steel strip rolling. The components include preheating section, heating section, air cooling section and water mist cooling section.
⑥ Pickling section, which is mainly used to eliminate the rust on the surface of the steel strip during annealing in the furnace area. The components include neutral salt electrolysis area, scrubbing area, pickling area, cleaning section and dryer, etc. During the stainless steel annealing and pickling production, HF + HNO3 mixed acid pickling is often used to remove the oxide layer on the surface of the steel strip produced by the annealing process of the hot rolling mill, and at the same time, the stainless steel surface is passivated by pickling to enhance the corrosion resistance of the steel plate.