KnowledgeBase » Welding

Weld Slag Clean Up Requirements for Galvanizing

When welded structures are hot-dip galvanized, the weld area cleanliness significantly affects the quality and appearance of the galvanized coating around the weld.  If a coated electrode (i.e. a flux-coated welding wire/rod/stick) is used during welding, all welding flux and slag must be cleaned prior to galvanizing or the ...
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Is hot-dip galvanized steel considered anti-sparking?

Yes, hot-dip galvanized coatings are anti-sparking and non-incendiary as are most zinc coatings. The exception is zinc coating alloys that have 30 to 55% aluminum. It is important to realize if the galvanized steel is struck hard enough, and the zinc coating is penetrated all the way down to the base steel, then the steel could spark of course. Source: Corrosion Resistance of Zinc and Zinc Alloys, by Frank Porter, pg. 97
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What welding material yields normal zinc coatings?

For stick rod application, Lincoln Electric’s Fleetweld 35 LS (AWS E 6011) seems to work quite well to produce a galvanized coating thickness closest to the coating thickness of the surrounding unwelded galvanized steel area, as long as the steel itself is not reactive, i.e. doesn’t have high (between 0.04% & 0.15% or > 0.25%) silicon levels.  For submerged arc welding (SAW) L60/80 (AWS F6A2-EL12) material tends to yield zinc coatings ...
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Avoiding warpage and distortion of hot-dip galvanized articles

ASTM A384, Standard Practice for Safeguarding Against Warpage and Distortion During Hot-Dip Galvanizing of Steel Assemblies identifies factors and types of assemblies and weldments prone to shape change due to the heating and cooling incidental in the galvanizing process.  Specifically, light gauge material (20 gage to < 1/4”) welded or ri...
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