Chemical pickling

Why chemically pickle stainless steel?

The corrosion resistance of stainless steel is based on the formation of a very thin chromium oxide-rich passive layer, which is formed only on metallically pure stainless steel surfaces.

Scale layers, welding colours and tarnish, ferritic impurities (e.g. abrasion) and mechanical processing (e.g. grinding, blasting, etc.) inhibit the formation of a closed passive layer.

Only fully controlled pickled stainless steel surfaces and weld seams therefore guarantee full corrosion resistance of the material and offer a decorative metallic appearance.

Comparison welded seams and untreated
Comparison welded seams and untreated

Pickling of stainless steel – how is it done?

Chemical pickling processes

  • Bath pickling
  • Spray pickling
  • Circular pickling
  • Local weld seam pickling

Technical procedure

Depending on the requirements and size of the workpieces, the components to be pickled are immersed into pickling baths or the pickling medium is sprayed directly onto the metal surface and rinsed off with conditioned (demineralised) water.

The chemically pickled components are then passivated and acid-free rinsed with conditioned water with limited conductivity.

Even the pickling of stainless steel tube systems is no problem for us. The systems to be treated are pickled and passivated with a circulating rinse.

Our services

  • Machining of workpieces of any size (pickling baths up to 80,000 litres)
  • Processing documentation
  • Execution of pickling work, including on-site work
  • Development and delivery of chemicals for pickling and passivation
  • Delivery of pickling equipment and spraying equipment for pickling.

There are next to no limits when it comes to the pickling treatment. Practical examples include:

  • Tubes, tube systems, fittings,
  • Special parts,
  • Heat exchanger tubes, tube bundles and plates,
  • Fences, railings and handrails,
  • Storage tanks, mixing and batch tanks,
  • Cryostats, fermenters, agitators and built-in components,
  • Reactors
  • Installations and complete systems,
  • and much more.

Every material has particular characteristics. The composition of the metallic alloy has a considerable effect on the pickling treatment. HENKEL pickling supports the following materials, amongst others:

  • High-alloy steel alloys,
  • Copper & copper alloys,
  • Nickel & nickel alloys,
  • Titanium & titanium alloys,
  • Niobium & niobium alloys.

Interested?

Ask today about the machining options for your components. We would be happy to give you a non-binding offer.