Abstract:2205 duplex stainless steel (DSS) possesses favorable mechanical property and good corrosion resistance at the same time, and has been a new material and applied widely in petroleum,natural gas, ocean and chemistry industry etc from 1980's in some advanced countries and from 1990's in China. One natural gas headstream project possesses abundant natural gas and provides 80， of total quantity gas for West-East Pipeline Project. The project includes a 13 km length pipeline and a gas treatment plant that purify gas about 12 × 109 m3 every year. The Cl- concentration in the water separated from gas is about 10，, and so the corrosion of medium is very violent to the pipeline. 2205 DSS material has been applied successfully to the project in 2004. This is the first time of such a mass of DSS material application in a project in China. The characteristic of 2205 DSS and application in natural gas pipeline project has been introduced in this paper.
