orange colored residual on 9018b3 weld
orange colored residual on 9018b3 weld
(OP)
we are welding t-22 w/ 9018b3 and are getting a residual orange colored like rust residue on weld. What is this?
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orange colored residual on 9018b3 weld
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RE: orange colored residual on 9018b3 weld
how long after the weld does the residue show up?
did they firehose the boiler after you welded?
RE: orange colored residual on 9018b3 weld
RE: orange colored residual on 9018b3 weld
I've seen this several times over the years and have received numerous reason for the residue. With SMAW you will see this residue when welding with a long arc. Was told that this was from the Cr electrode and others from the flux. the remedy was to shorten the air, let the coating almost drag on the weld puddle. In TIG and MIG it is supposed to be because you loose the shielding gas for some peroid of time. This happens a lot on SS, again it the oxidation of the Cr. It is the same for the yellow fumes you sometimes see around welding. I've never seen anybody that seem to worry about it except to clean it off during after the weld was completed..
Though I've never analysed the residue I think the Cr idea is approaching the cause though I believe Fe enters into the picture because in a Steel mill a lot times you see yellow fumes prior to red fumes.
When we used to cut SS with an iron powder rig you would see yellow appearing fumes before the red cloud appeared.
RE: orange colored residual on 9018b3 weld
RE: orange colored residual on 9018b3 weld
Chromium Trioxide is a orange brownish color which I believe will form in an arc. Taking into account that you are going to have other metals present in the fumes, I don't think orange/yellow fumes or yellowish deposit are out of the question. As you always lose Cr when welding an alloy containing CR the little information that I posted may not be too far fetched even if some is caught in the slag..
I could be way out in left field, they want let me play center field.
RE: orange colored residual on 9018b3 weld
RE: orange colored residual on 9018b3 weld
RE: orange colored residual on 9018b3 weld
the oxide film from the older tubes and those non-T22 and the firing of coal (even after a power washing) is leaching (for lack of a better word) into the new welds.
as said above just wire brush after each pass and do not worry about it.