... ; corrosion protection in gates of bridges and irrigation works; rustproof, de-oxidation, and paint removal for metallic parts.Main structureInner layer ... needs to be re-determined as the customer’s requirement. 2.Requirements for special working pressure, length, or colors may be ... ,1,1-1/4,1-1/2,1-3/4,2,2-3/8,2-1/2,3,3-1/2,4,5,6,7,8 ... ,10,12,18 ect. 2 inch concrete ...