I have encountered cases where two roughly 24" long 1/4" welds were done to a
plate embedded in concrete and "fried" the concrete. By "fried", I mean that
the concrete was discolored and had lost most of its strength from the heat
(could easily be chipped out). To solve the problem, we specified 2" skip welds
in place of the continuous weld, and we may have called for a paused between
welds to allow the heat to dissipate. For smaller welds, I have not personally
heard of any problems.
"Polhemus, Bill" wrote:
> I have a situation where I need to weld (vertical position) some 1/4" plate
> that is set against a concrete wall. The weld would just be a partial-pen
> weld, AWS prequalified weld joint designation B-P1c.
> My question is: is there anything I must do to protect the concrete directly
> behind the weld? Or is this not a problem?
> Your comments, please.