50051

Cooling coil material for HF acid etch bath?

September 17, 2008

We are anodising aluminium sheet parts since a long time, but recently have to anodise Silicon- bearing cast parts. These are first etched by us in dil 5% HF bath in plastic (PP) tank at room temp (about 30C),then swilled in dil nitric acid bath before anodising. The results are acceptable to the buyer. However, we face the problem of HF bath heating up incresingly as subsequent batches are treated in it.Could anyone suggest the cooling coil material to be used in this HF bath. Any help would be highly appreciated.

Malvinder Nagi
Partner in anodizing shop - Delhi, India

PTFE(polytetraflurethylene) also known by the tradename TEFLON

Gene Packman
- Great Neck, NY

Hi Malvinder

What Gene says makes sense but also investigate a material called PVDF .... should cost far less... available,I believe, from G.F.Fisher

Freeman Newton - White Rock, B.C. Canada