Abstract：With the increase of transportation pressure and the requirement for transportation efficiency of long-distance pipeline，X80 steel is gradually used on a large scale in the long-distance gas pipeline. As the chemical component is the steel "gene"，analyzing the evolution of chemical composition and determining the appropriate target value are important to solve manufacturing，welding and other problems. There is no engineering application of X80 pipeline in synthetic natural gas pipeline until today. In order to meet the needs of Xinjiang synthetic natural gas export pipeline project being built by Sinopec，the study of X80 pipeline steel should be strengthen.
2016, Vol. 26 
