Manufacturing of X100 Pipes for the TAP Project

The application of high strength steels like X100 are considered as an economical necessity in order to supply large volumes of gas over long distances in a competitive manner. The development of the grade X100 started more than 10 years ago and has progressed significantly. Therefore the focus of actual development and research work is focused on questions regarding the installation and the service behaviour of such high strength steels. In this context the TAP project has been launched by the ENI group in order to provide answers regarding the economic viability, the technological reliability and the real possibility of constructing high pressure pipelines with this newly developed steel grade. In this paper the manufacturing of line pipe in grade X100 for the TAP project including the two fibre reinforced crack arrestors will be summarized and the production results regarding strength and toughness we presented. Furthermore the analysis of tensile test results regarding the influence of specimen type, anisotropy and the effect of thermal treatment (low temperature ageing) on the stress-strain curve will be discussed.