Heat transfer analysis in API X70 steel joints performed by double submerged arc welding process

The longitudinal welds of pipelines are, preferable, performed by submerged arc welding procedure (SAW) with multiple arcs in order to increase the productivity and to achieve better mechanical properties of the welded joints. This research focuses on theoretical investigations of temperatures field in the welded joints achieved by double SAW process on API X70 steel, used in pipeline fabrication. The authors developed a 3D model of butt-joint using double SAW procedure, in distinct melted pools, using commercial finite element software MSC.Marc. Finally, numerical results on the temperature field are analysed and discussed and important conclusions are drawn.