Hot-Dip Galvanizing Process for Scaffolding and Formwork
Feb 02, 2026| The hot-dip galvanizing process for scaffolding and steel formwork follows the standard hot-dip galvanizing procedure, with Q235/S235 carbon steel as the base material. The whole process centers on decontamination → activation → galvanizing → cooling, featuring standardized operation and suitability for mass production-this is also a key process concern for overseas customers. The core steps are as follows:
Acid Pickling for Rust Removal: Immerse the steel in hydrochloric/sulfuric acid solution to remove surface scale and rust, ensuring zinc coating adhesion.
Rinsing and Neutralization: Rinse off acid pickling residues with clean water, then neutralize surface acidity with weak alkaline solution to prevent blistering of the subsequent zinc coating.
Fluxing Treatment: Immerse in a zinc chloride/ammonium chloride mixed solution to form a protective film on the steel surface and improve zinc coating bonding.
Hot-Dip Galvanizing: Immerse the dried steel in molten zinc liquid at about 450℃, forming a uniform and dense zinc-iron alloy layer plus pure zinc layer on the steel surface.
Cooling and Passivation: Cool with clean water after fishing out, then conduct passivation treatment to enhance the corrosion resistance of the zinc coating and prevent surface white rust.
Trimming and Inspection: Remove surface zinc nodules and burrs, inspect the thickness and uniformity of the zinc coating to ensure compliance with international EN/ISO standards (a must for foreign trade export).