Zinc-Coated Ductile Iron Pipe

Zinc has been used to protect ferrous materials against corrosion for many years. Metallized arc-spray zinc coatings are now available on ductile iron pipe produced in the United States. Zinc-coated ductile iron pipe has been widely accepted and specified in the 18 months it has been available. This paper will present an overview of corrosion principles, how zinc is applied to ductile iron pipe, how zinc inhibits the corrosion of ferrous materials, and additional enhancements that, in combination with zinc, further extend the life of an already long-lasting product. The paper will also briefly highlight the performance characteristics of ductile iron pipe related to pressure, surge, flow characteristics, thrust restraint, and sustainability.