Chemical methods can remove high temperature oxide and iron contamination without damaging the surface finish. Electropolishing may improve the surface finish. Since they remove the surface layer by controlled corrosion, chemicals will also selectively remove the least corrosion-resistant areas such as the chromium-depleted zones.
Spot Remover aids in cleaning of stains, spots of oil, grease & other stains, annealing colorations, rust contaminations, welding marks and burns. These chemicals are also suited to clean rusted domestic fittings.
Tank immersion, spray pickling and passivation treatments should be entrusted to competent fabricators or stainless steel finishing specialists. The selection and control of these potentially hazardous processes is critical for ensuring that satisfactory corrosion resistant finishes are obtained.
Pickling/ cleaning operations following a typical manufacturing programme could be:
- Grinding for removal of defects caused by welding, for slag removal after welding
- Removal of organic contamination
- Pickling using a bath, paste or solution, possibly in combination with a careful mechanical treatment to break oxides
- Thorough rinsing with water, preferably using high-pressure water jet
Main standards to abide by are:
- ASTM A380: Practice for cleaning, Descaling and Passivating of Stainless Steel Parts, Equipment and Systems
- ASTM A967: Specification for Chemical Passivation Treatments for Stainless Steel Parts
Key Features and Benefits
- Corrosion protection
- Adheres/ sticks to vertical surfaces
- Restores protective layer on metal surfaces
- Extends metal life