Hot dip galvanized bolts (HDG bolts) are widely chosen for outdoor, coastal and humid environment construction. Unlike electroplating, hot dip galvanizing forms a thick, uniform zinc alloy layer on steel surface.
The zinc coating thickness usually ranges from 85μm to 100μm. It provides both barrier protection and sacrificial anode protection. Even if the coating gets scratched, the surrounding zinc will sacrifice itself to prevent the steel substrate from rusting.
HDG fasteners are popular for bridges, solar brackets, highway guardrails and waterfront facilities. The only downside is thicker zinc layer, which may affect thread fit. We can supply over-tapped HDG nuts to solve assembly problems. Compare HDG with zinc plating when selecting fasteners for anti-corrosion projects.