Engineers(?) tampering with corrosion test results
Engineers(?) tampering with corrosion test results
(OP)
Came across a description of engineers tampering with corrosion test results http://www.finishing.com/422/11.shtml
It deals with zinc plating that was salt spray tested per ASTM B117. To those unfamilar, at the end of the salt spray
"The specimens shall be carefully removed.
Specimens may be gently washed or dipped in clean running water not warmer than 38oC (100oF) to remove salt deposits from their surface, and then immediately dried. Drying shall be accomplished with a stream of clean, compressed air."
The engineers(?) were wiping off the white residue (zinc corrosion is white), asserting that it was salt. Pretty unprofessional. Was my response appropriate?
It deals with zinc plating that was salt spray tested per ASTM B117. To those unfamilar, at the end of the salt spray
"The specimens shall be carefully removed.
Specimens may be gently washed or dipped in clean running water not warmer than 38oC (100oF) to remove salt deposits from their surface, and then immediately dried. Drying shall be accomplished with a stream of clean, compressed air."
The engineers(?) were wiping off the white residue (zinc corrosion is white), asserting that it was salt. Pretty unprofessional. Was my response appropriate?





RE: Engineers(?) tampering with corrosion test results
Were you going to respond about the black spots the poster asked about?
TTFN
RE: Engineers(?) tampering with corrosion test results
Black spots can be due to porosity in the zinc plating, some reaction between zinc, chromate & humidity, or contamination of some type. No chromate details were given & my experience is nearly all with hex Cr, so it would have been unprofessional to guess.
RE: Engineers(?) tampering with corrosion test results
Mike Halloran
Pembroke Pines, FL, USA
RE: Engineers(?) tampering with corrosion test results
It is likely that the "engineers" mentioned are not P.E.s.
It is not clear from the OP that anything fradulent actually occurred, it may have only be "debate" between engineering and QA.
However, as you pointed out, B117 is pretty clear. They do appear to be either too lazy to read it, or too stupid to understand it.
RE: Engineers(?) tampering with corrosion test results
http://www.answers.com/topic/salt
second defintion
Cheers
Greg Locock
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.
RE: Engineers(?) tampering with corrosion test results
Although ZnCl2 is a salt, chemically speaking, it is very water-soluble and drips off the surface during salt spray testing, and none will remain after rinsing. White residue is Zn(OH)2 which I believe is not considered a salt.
RE: Engineers(?) tampering with corrosion test results
RE: Engineers(?) tampering with corrosion test results
RE: Engineers(?) tampering with corrosion test results
dik
RE: Engineers(?) tampering with corrosion test results
TTFN
RE: Engineers(?) tampering with corrosion test results
Your replies are just fine, and drive the point(s) home.
RE: Engineers(?) tampering with corrosion test results
Why do you think it's an ethics thing and not just an issue of people who don't know what they're doing?
The probably need training on ASTM B117 more than they need ethics training.
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RE: Engineers(?) tampering with corrosion test results
Like having the pilot on your flight qualified by having slept in a certain hotel [a television commercial in the US]???
To Greg: Zinc corrosion in the salt spray test is "white rust"
thread338-164597
Is that expression also used outside N. America?
RE: Engineers(?) tampering with corrosion test results
If it doesn't actually, specifically say, "no wiping", or words to that effect, some people would assert that wiping is allowed, because it's not expressly prohibited.
Mike Halloran
Pembroke Pines, FL, USA
RE: Engineers(?) tampering with corrosion test results
RE: Engineers(?) tampering with corrosion test results
Actually, ASTM is rather explicit: "Unless otherwise specified...specimens shall be treated as follows..."
then gives the rinsing procedure described above.
RE: Engineers(?) tampering with corrosion test results
I have, however, worked with individuals who:
- are alleged to be engineers.
- believe they can flex rules _because_ they are engineers.
- don't read particularly well.
- interpret what they do read, with a lot of, er, latitude.
- dress fashionably.
- keep their jobs, and get promoted, despite the odd and unfortunate things that happen on their watch.
I think that 'fraud' requires deliberate deception, and may therefore be too strong a word for the extant case. But 'incompetence' seems too weak a word.
Mike Halloran
Pembroke Pines, FL, USA
RE: Engineers(?) tampering with corrosion test results
The ultimate responsibility need to be very clearly defined and who ever has it must supervise effectively. I think we can all reach this conclusion witout too much trouble but one thing everyone should be aware of is the dangers inherent in "routine" activities, this is where catastrophies start.
It has to be a natural expectation that routine tasks can quickly become corrupted and more quickly if not supervised with intent.
If inspections are justified or required then there must be an element of involved supervision even if the grunt work is delegated.
This is an interesting and informative case:
http://www.hse.gov.uk/nuclear/mox/mox1.htm
A lot of money was spent on this investigation and they clearly state they have no idea as to motive.
The opening link in this thread ought to be worrying because the guy who raised the question is presumably the "responsible supervisor" needing to get outside advise on a test he is responsible for and which is delegated to others to do.... training should start at the top and the test should surely be throughly understood by the supervisor before it is delegated down.
JMW
www.ViscoAnalyser.com
RE: Engineers(?) tampering with corrosion test results
Dik
RE: Engineers(?) tampering with corrosion test results
The number of hours before white rust in the salt spray test is a measure of the quality of the chromate coating.
E.g., in thread338-164597, the minimum for Type II chromated zinc per ASTM B633 is 96 hours. White rust before this time constitutes failure. Many platers are having problems since switching from proven hexavalent chromium formulae to new, trivalent chromium (less hazardous to health & environment).
The number of hours before red rust (rusted steel substrate) is a measure of the quality of (zinc plating + chromate).