Stainless Steel Handling and Cleaning
Stainless steel cleaning is very important to increase its service life as well as to keep its aesthetic look retained. Stainless steel do require cleaning on a regular but very less frequent manner. Its cleaning frequency depends on the environment where it has been used. When Stainless steel can not be protected by a covering, procedures must be employed to keep the material clean. Hard water dripping, dirt from neighbouring operational activity, unclean handling of equipments etc can be causes of subsequent stains. The most severe problem arises in the shop that work in both carbon steel and stainless steel.
Apart from regular cleaning, fabrication care must also be taken to keep stainless steel clean before and after fabrication.
Contamination by contact with mild steel or alloy steel as well as sources of carbon contamination like varnish, paint, wax, marking pens etc., should be avoided. Cutting shears hold down pads, abrasive cut off wheels, toolings & equipment for roll forming, bending, drawing etc., shall be wiped off to make them free of adherent mild steel particles, oil or grease before use on the surface of stainless steel. The edges of thermally cut stainless steel should be cleaned by machining or grinding to remove surface contamination, particularly iron.
Weldments with heat tints also need cleaning which can be done either mechanically, chemically or electrochemically. All weld spatter and flux or slag should be removed by using clean grinding wheels. Weldments should be smooth and passivated after cleaning and grinding.
Cleaning Methods for different conditions
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| Condition of Surface |
Cleaning Agent |
Method of Application |
| Atmospheric and construction Dirt |
Soap/Detergent and water |
Sponge and rag. Rinse with water, wipe dry |
| Heavier Dirt Containing oil or Greece |
Organic solvents like
acetone benzene and Xylene |
Sponge or rag. Rinse with clean
water, wipe dry. Observe safety rules
(googles, gloves etc) |
Rust discoloration
from other
materials. |
Commercial pickling
pastes, diluted nitric
acid (15% by volume) |
Clean cloth or sponge – let
stand for 20 min. Rinse and repeat
20 min. Rinse and repeat if necessary.
Observe safety rules (goggles, gloves etc.) |
Heat tint or heavy
discoloration |
5% oxalic acid (warm)
5-15% nitric acid or
5-10% phosphoric acid &
follow with neutralizing rinse |
Swab or immerse.
Observe safety rules
(goggles, gloves etc.) |
Oil grease, fatty
acids (without swabbing). |
4-6% solution of sodium
metasilicate/trisodium phosphate. |
No swabbing required. |
Oil grease, fatty acids (with
swabbing). |
Carbon tetrachloride,
trichloroethylene, acetone,
kerosene, gasoline, alcohol. |
Rub with cloth. Observe
safety rules (goggles,
gloves etc.) |
Hand and
fingerprint smears. |
Calcium carbonate fine
powder, waxbased polish |
Rub with cloth. |