Hot-dip galvanizing coats steel fasteners — including structural bolts, weathering steel bolts and tension-control bolts — with zinc by immersing them in molten zinc. The coating is thicker than many electroplated finishes.
The thicker coating improves outdoor corrosion resistance, but it also affects thread fit. Matching nuts are usually tapped oversize after galvanizing.
Buyers should confirm coating standard, coating thickness, thread tolerance and whether the assembly will be exposed to salt or chemical environments.
