Material

The steel bars preparing for being coated shall avoid the contamination of grease and oil and have no burr or other defects on their surface. The quality of steel bars shall be in accordance with valid national standard specification.

The coating material shall be produced by special manufacturers and consistent with C1 in Appendix C of JG3042-97.

The sealing material shall be supplied by special manufacturers and compatible with coating material. It shall be inert in concrete and in compliance with C1 in Appendix C of JG3042-97.

Manufacturing process

The coated steel bars are manufactured on assembly lines. The manufacturing process involves the following steps: Surface preparation (grit blasting) --preheating--electrostatic sprayin--water quenching--quality testing--packing--stocking.

Reinforcing steel bars are blast-cleaned to a near-white metal finish (Sa 2.5) using abrasive grit, which also roughs the surface of steel bars in order to give it a textured, anchor profile assuring the maximum adhesion between coating and steel substrate. After blast cleaning, at no time shall there be contaminants of mill scale and rust, which will affect coating quality.

After surface preparation, steel bars are preheated to certain temperature by induction heating.

The preheated steel bars are sprayed with epoxy resin powder when passing through electrostatic spray booth. The powder melts to form uniform film, which is allowed to cure in a short time and then hardens to be inert and corrosion-proof coating.