Steel pickling and oiling is a metal surface treatment finishing process used to remove surface impurities such as rust and carbon scale from hot rolled carbon steel. The steel is submersed in a bath of pickle liquor, a solution of Hydrogen Chloride acid, to remove the impurities from the surface of the steel.
Wilton Steel Processing, Inc. performs batch pickling and oiling of hot rolled carbon steel products of many different types. We can pickle flat bar, angles, tubing and plate material up to 26’ long; we also can do certain smaller specialty parts. A basic overview of our process:
- Loading: Each rack is carefully loaded by separating individual pieces of material in rows on the rack. Each row is separated with angles in insure that our solution will reach every square inch of material
- Cleaning: The rack is then placed in a highly alkaline (sodium hydroxide based) cleaner in order to remove soils and oil from the surface of the metal.
- Rinsing the rack of steel is then thoroughly rinsed in two tanks to remove the cleaner from the material and to reduce the P-H before pickling.
- Pickling: The rack is then immersed in hydrochloric acid (HCI) for as long as it takes to remove the scale, rust and corrosion from the surface of the product.
- Rinsing: The rack is then rinsed in two tanks to remove the hydrochloric acid from the surface of the material.
- Cleaning: The rack is placed back into the alkaline cleaner in order to completely neutralize any acid residue that may remain on the surface of the steel.
- Final Rinse: Our final rinse tank removes the cleaner from the material surface.
- Oiling: The rack is then placed in either water soluble oil or a mineral based oil to prevent flash rust from forming on the pickled steel while it awaits further fabrication.