Conventional Situation Ductile iron pipe and fittings are manufactured having a cosmetic application of NSF-sixty one Qualified sealcoat, black asphaltic paint on their exterior surfaces, and a thin Portland cement lining inside. The freshly placed cement lining is likewise normally sealcoated over the Preliminary curing method. Epoxy coatings: Epoxy coatings https://www.pinterest.com/pin/993958580252143889/