Investigation of Polyethylene Pipeline Behavior after 30 Years of Use in Gas Distribution Network

Polyethylene (PE) gas pipes are introduced in Algeria in 1978 to substitute the old pipelines made by copper, steel and cast iron. These later were used for the distribution of natural gas with medium working pressure of four bars. In this study, the polyethylene pipes were extracted from the Algerian distribution gas network in order to study their characteristics after more than 30 years of use. Two different pipe diameters (o63 and o125) with different ages of use were characterized according to the specifications on the EN1555-2 standard. The dimensional, physical and mechanical tests were performed with the same parameters as a newly produced pipe. The results showed that most of the characteristics are still fitting the EN 1555-2 specifications except for the density and the oxidative induction time. These two later will be considered as two basic parameters for the future studies of the polyethylene aging.