Pickling of bright steel

At Kröger Works’ surface treatment facility, we perform pool and spray pickling for stainless and acid-resistant steels. We handle both large assemblies and small components.

Corrosion resistance and appearance

Heat treatment or welding forms an oxide layer on the surface of stainless and acid-resistant steels, along with a zone beneath it with low chromium content. Removing these zones and forming a passive film is crucial for the corrosion resistance and appearance of the product.

The best corrosion resistance is achieved through chemical treatment, i.e., pickling.

The most common method for coating bulk goods as well as strip, tube, and sheet products is mixed acid coating in a mixture of nitric acid (HNO3) and hydrofluoric acid (HF). The purpose is to remove the last remnants of the oxide layer, dissolve the chromium-depleted zone, and form a passive surface.

We consider environmental impacts

At Kröger Works’ pickling facility, special attention has been paid to the environmental impacts of the plant. All process waters are treated in our own wastewater treatment plant, which meets strict environmental requirements, before being discharged into the sewage network.

The wastewater treatment plant has met its requirements very well. It has achieved a 98 percent purification efficiency for chromium and nickel in the wastewater. The concentrations of other heavy metals also significantly fall below the limit values required by the sewage agreement.

Thanks to the high-level purification process, 30–50 percent of the treated water can be reused in the pickling process as washing and rinsing water.

The pickling facility operates an air purification system that already meets future tightened requirements. Only purified rinsing water is used in the purification process, which is recycled through the treatment plant in the process continuously.

The pickling facility of Kröger Works

The pickling facility of Kröger Works enables the pickling of stainless and acid-resistant steels through both pool pickling and spray pickling.

  • Facility area: 1000 m2
  • Coating pool: Length 13,410 mm, width 3030 mm, depth 3200 mm, liquid surface 2800 mm, volume 115 m3
  • Door sizes: 5,450 x 5,500 mm and 4,500 x 5,000 mm
  • Cranes: 2 units of 20,000 kg cranes

Ask for more information or request a quote

Ask for more information or request a quote by calling or emailing us.