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Posted by Private on March 23, 2008, 6:49 pm
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> Put them on a gas barbecue grill if you have one -- that will get a lot
> hotter than your kitchen oven, and will eliminate the wife factor...
>
IIRC the major gas given off by burning propane is water vapor.........
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Posted by Serial # 19781010 on March 23, 2008, 6:52 pm
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On Sun, 23 Mar 2008 13:39:28 -0500, "Alan Andrews"
>Some time ago I purchased a 50# box of E7018 Hobart electrodes. I'm not a
>professional welder, nor do I have occasion to do that much welding, which
>means that I had an open box of low hydrogen exposed to atmospheric humidity
>for quite some time, like a year.
>
>I'm in the midst of building a custom steel fence on the front of my
>residence property and some of the welding will be done with low hydrogen.
>At the local welding supply I mentioned in passing the story about the
>opened rods and asked if low hydrogen rods actually "got old," like I'd
>heard for ever. They indicated that they did indeed degrade, such so that
>they couldn't even be reconditioned in an oven.
>
>When I got home I called Hobart and spoke with a technician who said that
>once low hydrogen was exposed to the atmosphere, it immediately started
>*irreversibly* degrading, and that, yes, re-drying them in an oven didn't
>help. I said that that would seem to indicate that a chemical reaction had
>taken place (with what I thought was rather inert inorganic material
>(rutile, for instance)) and he, sorta handwavingly (if that's a word) said,
>yeah.
>
>To confuse and confound the question, I found a document on the Web from
>Lincoln Electric that indicated that Lincoln E7018 could indeed be reclaimed
>by drying in an oven (http://www.jflf.org/pdfs/papers/fabguide.pdf, p. 7).
>So...what IS the story on storing an open quanity of 7018 for protracted
>periods, in out of the weather (my garage, for instance), but nonetheless
>exposed to Southern-style humidity.
>
>Thanks,
>Alan
>
I was involved in a huge nameless fabrication activity. Some of my
duties involved sampling Low Hy electrodes for moisture content.
There was a limit depending on the strength of filler material. There
was a limit to the exposure time and then you had to return the filler
material to be held, disposed of, or reconditioned @ >300 F as others
have mentioned. That being said, after the electrodes were
reconditioned a number of times, you could "rebake" the electrodes by
increasing the temperature to >800 F and then held for a set time to
"drive" off the moisture.
The Hobart tech knows the "small operator" does not have access to a
welding laboratory, mechanical and/or chem laboratory to perform full
procedure testing as we had access to (money for us was no object), so
its better (cheaper, easier, by thousands of dollars.) to sell you
another can of unopened electrodes(+ Hobart makes money).
We were required to open 10 lb cans of Low HY electrode and test them
for moisture. Since the material was moisture sensitive we were
required to dispose of any of the remainder from the cans. We used to
stick them on a pallet and occasionally, workers would stop by and ask
if we had any electrodes that they could have for "country jobs" (home
use, fence building?).
So, you have two types of welding, critical or non-critical. For
example, if your fence was likely to fall on someone walking by (or
like the attachment welds for that crane in NY), then yes it would be
considered critical. If your fence was just a visual embarassment to
your wife, family or others and if it fell over would not injure
anyone, than that would be considered non critical.
So, run a bead, grind it half way down, if you see any porosity or
other defects, then you probably wouldn't want to use that electrode,
if not, its probably still good to use for non-structural,
non-critical welding applications. Switch to E6011 or E6010 and be
done with it.
--
Posted via a free Usenet account from http://www.teranews.com
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Posted by Ernie Leimkuhler on March 25, 2008, 2:15 am
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> Some time ago I purchased a 50# box of E7018 Hobart electrodes. I'm not a
> professional welder, nor do I have occasion to do that much welding, which
> means that I had an open box of low hydrogen exposed to atmospheric humidity
> for quite some time, like a year.
>
> I'm in the midst of building a custom steel fence on the front of my
> residence property and some of the welding will be done with low hydrogen.
> At the local welding supply I mentioned in passing the story about the
> opened rods and asked if low hydrogen rods actually "got old," like I'd
> heard for ever. They indicated that they did indeed degrade, such so that
> they couldn't even be reconditioned in an oven.
>
> When I got home I called Hobart and spoke with a technician who said that
> once low hydrogen was exposed to the atmosphere, it immediately started
> *irreversibly* degrading, and that, yes, re-drying them in an oven didn't
> help. I said that that would seem to indicate that a chemical reaction had
> taken place (with what I thought was rather inert inorganic material
> (rutile, for instance)) and he, sorta handwavingly (if that's a word) said,
> yeah.
>
> To confuse and confound the question, I found a document on the Web from
> Lincoln Electric that indicated that Lincoln E7018 could indeed be reclaimed
> by drying in an oven (http://www.jflf.org/pdfs/papers/fabguide.pdf, p. 7).
> So...what IS the story on storing an open quanity of 7018 for protracted
> periods, in out of the weather (my garage, for instance), but nonetheless
> exposed to Southern-style humidity.
>
> Thanks,
> Alan
The rule I have worked by is that unless the rod was soaking in water,
(which will break down the binders in the flux), you can usually bring
the rod back to usefulness.
However,the first test to see if the rod can be salvaged is easy.
Take a sample rod, or a few, and bend it in a tight "U" shape until the
flux breaks off.
If thew wire inside is rusted, trash it.
If the wire is OK, then roast it.
Lincoln has the PDF about roasting in an oven for a long period.
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> hotter than your kitchen oven, and will eliminate the wife factor...
>