Scale Problems on Steel

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We need to remove weld scale and glass from steel parts that have a particularly bad looking weld. Our normal treatment uses 2 mins in a 20% Sulfuric(Cathodic) to help remove the scale prior to plating with Nickel. We have tried the following without much success: Longer immersion times in the 20% Sulfuric, Alkaline Permangante Solution @100g/L at 120 degrees F, and media blasting. Media Blasting works everytime but we are not set up to run this kind of volume I am looking for other alternatives.

J. Ott
plating shop - Hbg, PA

First of two simultaneous responses -- +++++++

Try pickle paste (brush-on) from a welding supplier.

Alkaline permanganate scale conditioning is usually performed at higher temperatures, 160 to 180°F (71 to 82°C).

Ken Vlach
- Goleta, California

Second of two simultaneous responses -- +++++++

Gentleman,
If usage of Cyanide is not restricted,you can try using the following composition in Periodic reverse current cleaning,10 seconds forward and 20 seconds reverse for a period of 15 mts.

Sodium Cyanide 60 gram/litre and Sodium Hydroxide 60 gram/litre.
Temperature shall be ambient.

SHANKARANARAYANAN N
- Bengalooru, Karnataka, India