Pickling & Passivation

Pickling and Passivation are chemical treatments which remove any surface contaminants and help to reestablish the passive layer. This is generally a requirement for fabrications used in process engineering and water treatment plant, but can also have applications in construction.

Box section and angle fabrication - Pickled

Pickling

Welding stainless steel produces a coloured oxide layer and a depleted chromium layer. This can be removed by the use of pickling pastes which remove this surface layer.

The colour can also be removed by mechanical methods, however this can also introduce other ferrous contaminants.

For some fabricated components it may be appropriate to immerse the entire fabrication in a pickling solution. These are usually solutions of nitric (HNO3) or hydrofluoric acid (HF). The solution removes any weld colour, scale, the depleted chromium layer and any other iron contaminants. It restores the fabrication to a uniform condition.

Pickled and passivated fabrication

Passivation

Passivation aids the development of the passive film on the surface of stainless steel. This is usually a nitric acid solution (HNO3).

Both pickling and passivation use dangerous acid solutions and this process is usually undertaken by a specialist subcontractor. Talk to your sales contact about your requirements.

Welded tube and flange detail  - pickled and passivated

Need Holes or Slots?

We punch holes or slots in stainless steel or mild steel plates. The Punched Holes diameter must be greater than the plate thickness. Holes less than the plate thickness must be drilled - please contact the Sales Desk for a price
Holes or slots in Stainless or Mild Steel to your specification

How Accurate?

Download our Cutting & Bending tolerance specifications PDF
Accuracy Tolerances and Specifications

How Soon?

Delivery and manufacturing lead times. Depending upon the size of the order we aim to despatch goods within 2-5 working days. Carriage cost depends upon the size and weight of the order, and the delivery address postcode.
Delivery and manufacturing lead times