Pickled Strip Steel
Pickled slit strip is the base material for a wide variety of products at our customers in the furniture, vehicle and construction industries. Therefore, excellent and consistent quality as well as the reliability of the product are important.
We therefore pickle hot-rolled steel strip in our own pickling plants according to the highest technical standards.
We supply the flat product descaled in this way as pickled slit strip or pickled wide strip. Our pickled slit strip is also used for our own production of pickled tubes and profiles, galvanized tubes and profiles and hot-dip galvanized strip steel. In this way, we can guarantee the best quality of the starting material in our downstream finishing stages.
Why is steel pickled?
During strip production, rolling and annealing during the manufacturing process causes a complex oxide layer, the "scale", to build up on the surface of the steel. Pickling removes this unwanted top layer and thus creates a metallically clean surface for further processing.
How does the pickling process work?
There are different processes for pickling steel. At Wuppermann, the steel strip is treated with a hydrochloric acid concentrate. Pickling with hydrochloric acid is more effective and energy-saving than, comparatively, the process with sulphuric acid.
First, the scale is broken up mechanically in the scale breaker and the strip surface is prepared for the subsequent treatment in the acid bath. The hydrochloric acid passes through the cracks and pores in the scale layer to the steel base. In the process, the oxide layer loses its grip on the substrate and dissolves chemically. The remaining acid residues on the strip surface are finally washed off in a ressource-saving cascade rinse in a resource-saving manner and the steel strip is finally dried. The result is a high-quality primary product with a light grey, slightly rough, metallically clean belt surface.
What happens with the acid?
All the hydrochloric acid used is recycled and flows through the pickling or regeneration plant in the process. Only small amounts lost during the process have to be replaced by fresh acid.
The waste product " iron chloride" can be further recycled and is used, for example, in mechanical wastewater treatment or textile printing.