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Carbon mark defect on piping product after pickling
I have been using HF+nitric for passivate but lately a few problem occur in the process. Those problem are: 1)the appearance of carbon mark 2)the appearance of acid mark those problem have slow down my production rate. I hope sir can recommend me the way to overcome this problem.
Thanks,
Lim Boon PinKanzen-Tetsu - Malaysia
Dear Mr. Pin,
You did not write that you passivate Stainless Steel but I understand that this is the case. You are not obliged to passivate with Hydrofluoric acid , omit the Hydrofluoric and you won't have the problems you described.
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Yehuda Blau
YB Plating Engineering and Quality - Haifa Israel
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