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Curated with aloha by
Ted Mooney, P.E. RET
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How to do Pickling solution analysis
Q. I am interested in technical books that describe the process of titrating nitric/HF acid pickling solutions to determine percentage of Nitric, HF and iron or titanium content.
The information should include a list of chemicals, equipment necessary to perform the analysis, the titration procedure, including any equations required to determine the % composition.
I would also like to have information on how much Nitric Acid/HF should be added to a tank on known volume to bring the tank up to specification requirements, once the analysis is complete.
Thanks in advance for your answer. I am reviewing our present process to perform this analysis.
Not being a chemist, I would like some starting point to know if our present process will yield accurate results.
metal bellows - Anaheim, California
2003
2005
Q. Hi There
Question stated above, I would also be interested in any applicable information.
My main objective is to obtain the procedure to analyze for iron & titanium content in a pickle solution of;
40-47% Nitric
2-4% Ammonium Bifluoride
Balance DI water
We use the solution for specific etching prior to penetrant inspection, & for a post shot peen cleaning operation.
Also thank you in advance,
Aerospace - Kitchener, Ontario, Canada
Hi. Similar, although not identical, questions have been asked and answered here several times before. So maybe start with letter 16977 and see if that helps. Also letters 15345 & 16849 and possibly 4626 & 5912. If one of those "almost" answers your question, maybe a follow-up there will get you the remaining missing info. Good luck.
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Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2005
How to know if a pickling solution is still usable?
Q. Can anybody help me how can I decide if a liquid for pickling (mainly HF and H3PO4) is still good enough for using? So for which parameters should I measure (besides examining the quality of the treated metal)? I mean if I used it once and I'd like to use it again, which parameters guarantee the same quality?
Thank you for your kindness!
- Budapest, Hungary
August 8, 2014
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