Pickling & Passivation SS/INOX

Pickling and Passivation on Stainless Steel

Stainless steel and Inox pickling and passivation are chemical processes that are utilized to provide protection to metals against corrosion and pitting. In Pickling and passivation process, an acidic solution is used to the metal surface to remove contaminants and process for chromium-oxide passive film after successful removal of Nickel, molybdenum and other metal. Without pickling and passivation, stainless steel is subject to corrosion which can lead to quality issues and job failure.

1. Degreaser

Before pickling or passivation of stainless steel or inox it must to remove processing oils and grease, organic contaminants present on the surface of the metal. If these contaminants are not removed before the pickling and passivation or passivation, it will have an adverse effect and the desired result will not be achieved.

2.Pickling liquid

Pickling Liquid is usually used in tank immersion or circulation and it is advantageous for treating all the fabrication surfaces at the same time for uniformity of finish and optimum corrosion resistance. Pickling liquid is circulated through a system of pipework and is particularly recommended for piping that will carry corrosive liquids.

3. Pickling Spray Semi Gel

Pickling spray semi gel is usually recommended for treatment of complete fabricated structures or tanks in which immersion or circulation is not possible. Pickling Spray semi gel has consistency so it can be sprayed with the help of pressure sprayer and it sticks to job for enough time so process gets completed. Pickling Spray semi gel advantageous for on-site treatment but proper acid disposal and safety procedures are essential.

4. Pickling Gel /Pickling paste

Pickling gel or paste is used for cleaning and passivating of welding joints and the heat affected area of welded stainless steel or inox fabrication. Pickling paste is applied with a special acid resistant brush. Pickling gel or paste has adhesive capacity and can be applied on vertical surfaces and formations or corners without any risk of running or drying. It is useful for spot treatment of welds and other intricate areas that require manual detail.

5. Passivation

Passivation is a chemical treatment with an acidic process that removes free-iron and other contamination from the stainless steel while simultaneously promoting the formation of a passive chromium oxide layer to act as a barrier to further corrosion. Stainless steel contains enough chromium to undergo passivation by forming an inert film of chromium oxide on its surface. Chromium produces a thin layer of oxide on the surface of the steel the passive layer that prevents surface corrosion.

6. Neutralizer

Neutralizer solution liquid alkaline solution to neutralize acid stainless steel pickling products and / or acidic surface after pickling and passivation. Neutralizer is the best way to ensure you are getting all of the pickling and passivation solution off your parts.


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