Weld Slag

The black/brown line is the arc weld slag that has not been chipped off after welding.  This cannot be removed by the normal pre-treatments in the galvanizing process.  If it is not seen prior to galvanizing, the weld slag will remain in place and the steel will not be galvanized underneath.  This responsibility rests with the the fabricator.  The weld slag needs to be chipped off and a paint repair with a zinc rich paint made.

black, line, brown, slag, weld, ungalvanized, lump

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