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Engineers(?) tampering with corrosion test results

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?

RE: Engineers(?) tampering with corrosion test results

A bit harsh, but may be necessary.  

Were you going to respond about the black spots the poster asked about?

TTFN



RE: Engineers(?) tampering with corrosion test results

(OP)
Thanks, I thought it gave a really bad image of engineers to the world, ergo harsh corrective action.  Some MIL specs do require product recalls back to the data of last verifiable qualification tests, which could bankrupt some suppliers...

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

You might have suggested that the white stuff be recovered from the wipers and sprinkled on the offenders' lunch.

Mike Halloran
Pembroke Pines, FL, USA

RE: Engineers(?) tampering with corrosion test results

Perhaps a bit harsh.

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

A little chemical knowledge is a dangerous thing, but salt is not just NaCl

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

(OP)
"A little learning is a dangerous thing."

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

What does being P.E. have to do with anything?  Perhaps the offending engineers where all wearing blue shirts.  Or maybe they all have 6 toes on their left foot.  Or maybe, just maybe, they just didn't follow the specification as written.  It isn't always some conspiracy of non-PE's to circumvent the system, just to stick it to the PE's.

RE: Engineers(?) tampering with corrosion test results

kenvlach...appropriate response, though wrong anatomy.

RE: Engineers(?) tampering with corrosion test results

What is the downside of wiping the specimen?  other than voiding the test...

dik

RE: Engineers(?) tampering with corrosion test results

And getting weird crap under your fingernails?  Particularly if you're one of those that chew their...

TTFN



RE: Engineers(?) tampering with corrosion test results

Quote (Ken V):

Your company needs tighter control of QA testing. ASTM B117 is pretty clear. No wiping. After water rinsing, remaining white stuff is zinc corrosion product. Chemically analyze for Zn if you want verification.

Option 1) Recall all parts shipped since the last verifiable, non-fraudulent salt spray results.
Option 2) Cut some fingers off the saboteurs, and require remedial courses in professional ethics.

Your replies are just fine, and drive the point(s) home.

RE: Engineers(?) tampering with corrosion test results

I think the Saudis or the Taliban would probably agree with your option #2.

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.

--------------------
How much do YOU owe?
http://www.brillig.com/debt_clock/
--------------------

RE: Engineers(?) tampering with corrosion test results

(OP)

Quote (Beggar):

Why do you think it's an ethics thing and not just an issue of people who don't know what they're doing?
"people who don't know what they're doing" violates every QA process requirement that I've read or written.  Definitely "an ethics thing" for non-QA engineers(?) to falsify results.  Unprofessional in any profession.

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

Maybe the specification could be more clear.

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

MikeHalloran, the spec explains what to do.  A spec can't possibly explain everything not to do.  A spec that listed everything not to do would go on forever.

RE: Engineers(?) tampering with corrosion test results

(OP)
Mike perhaps tells waiters not to spit (or worse) in the cup when he orders coffee or soup...

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

No, guys, I, personally, would follow the spec as written, especially with a UOS in the preface, and expect anyone on my team to do the same.

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

I suspect that inspections, routine inspections, are often delegated down the tree to "technicians". Delegation is fine if proper training is given and especially, ongoing supervision.
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

Quote:

It has not been possible to establish the motive for this falsification, but the poor ergonomic design of this part of the plant and the tedium of the job seem to have been contributory factors. The lack of adequate supervision has provided the opportunity. Despite this, self-discipline ought to have ensured that those involved followed the proper procedures.
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

I think we can agree that wiping is not permitted... but, can anyone tell me what the effect of this is?

Dik

RE: Engineers(?) tampering with corrosion test results

(OP)
Zinc plating on steel is often chromated for corrosion protection.  Several grades of chromating offer different degrees of corrosion protection of the zinc.

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).

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