Anti Rust Hot Dipped Galvanized H Section Steel for Outdoor Construction Framework

Hot-dip galvanizing immerses steel in molten zinc to form a metallurgically bonded zinc layer covering all surfaces (including inner walls), with 20-30 year corrosion life and self-healing scratches. Painting applies organic coating on surface, difficult to cover corners and inner walls, with 5-10 year life and easy corrosion at scratches. Galvanizing costs 30-50% more initially but has lower lifecycle cost. Prefer galvanizing for outdoor and corrosive environments.

Yes. But welding and cutting damage local zinc layer; after welding, must touch up with zinc-rich primer + galvanizing repair compound to ensure corrosion continuity. Drilling is recommended before galvanizing (fabricate-then-galvanize), so holes also have zinc protection; if drilling after galvanizing is necessary, hole inner walls must be coated with zinc-rich paint.

Per GB/T 13912, for steel thickness >=6mm, average zinc coating >=85um, local >=70um; for thickness <6mm, average >=70um, local >=55um. Inspect with magnetic thickness gauge, measure 5 points per member and average. We provide zinc thickness inspection reports at delivery.

Hot-dip galvanizing (440-460C zinc immersion) may cause slight deformation, especially for slender thin-walled members. We use proper racks and cooling process to control deformation, and straighten after galvanizing. Deformation is controlled within L/1000, not affecting installation.

Standard stock sizes: MOQ 1 tonne, ships in 3-7 days. Galvanizing required: MOQ 5 tonnes, 7-15 days (including 3-5 days galvanizing cycle). Large project orders can lock galvanizing capacity and deliver in batches per schedule.