High Quality Content by WIKIPEDIA articles! Ductile iron pipe is a pipe commonly used in potable water distribution. The predominant wall material is ductile iron, a spheroidized graphite cast iron, although an internal cement mortar lining usually serves to inhibit corrosion from the fluid being distributed, and various types of external coating are used to inhibit corrosion from the environment. Ductile iron pipe is a direct development of earlier cast iron pipe which it has superseded. Ductile iron has proven to be a better pipe material than cast iron in the 1970s but as costs have increased and the walls of the ductile iron pipe were made thinner, ductile iron pipe is increasingly having more leaks and premature failures. USU 2012 Study While ductile iron is still believed to be stronger and more fracture resistant; like most ferrous materials, it is susceptible to corrosion and retains some brittle characteristics. Relatively recent developments such as polyethylene or commonly called poly wrap or plastic bagging/sleeving have helped only marginally to mitigate true corrosion impacts, but it has pacified many in order to continue using ductile iron pipe in corrosive soils. A typical life expectancy of thicker walled pipe has been in excess of 75 years, however with the current thinner walled ductile pipe (a 76% reduction in size since 1908 1.58 inch to .38 inch in 1991 CL 150 DI), premature failure Corrosion can occur within 20 years in highly corrosive soils without a corrosion control program like Cathodic protection.