Sml Rainwater Pipe The material is cast iron with flake graphite as per EN 1561, at least EN-GJL-150. The inside coating of DS MLB fully meet EN 877; the outside coating corresponds to ZTV-ING part 4 steel construction,. Application:Construction drainage,bridge drainage system,pollution discharge,waste water rain water. Sml Cast Iron Pipe Painting:Inside:fully cross-linked epoxy thickness min.120μmOutside:two-layer thermal spraying zinc coating min.40μm + cover two-components epoxy coating 80μm silvery grey. Features:Flat and straight ; high strength and density without defect;easy to install and maintain ; long lifetime ,fireproof and noise resistant; environmental protection. Sml Rainwater Pipe