28040 2013 eng 130 140 conferenceobject Publishing house SPbSPU Saint-Petersburg state polytechnic university 0 -- -- -- To a large extend, longitudinally welded large-diameter pipes are used for modern oil- und gas-pipelines. Thereby the mostly applied base materials are made from the API-steels X65 and X70. Constantly increasing natural gas and oil delivery rates demand advancements of the assigned materials. Wall thickness minimization or operating pressure increase is achieved by material Substitution, e.g. employment of a high strength Steel grade API-X80, API-X100 or API-X120. For the production of such pipes a large plate is first formed to an open ring. Subsequent, it is continuously tacked along its longitudinal gap by means of a GMA-process. In the further process, the remaining double-sided joint gaps are filled up by cost-intensive multiple-wire submerged arc welding (SAW) processes. The GMA-tack weld is being completely remelted in the process. The maximal root face is dependent on the welding process and which is currently 8 mm. The innovative laser hybrid welding technology offers a significant increase in the full penetrated root face and welding speed, compared to conventional wielding technologies. It means for the pipe production, that the amount of SAW filier layers will be reduced and, parallel to that, the increased welding speed will led to the shortening of the production cycle for the longitudinal welded pipes. VII. International scientific and technical conference 'Beam technologies & laser application' (Proceedings) 30883 VII. International scientific and technical conference 'Beam technologies & laser application' Saint-Petersburg, Russia 18.09.2012 21.09.2012 0 Michael Rethmeier Sergej Gook Andrey Gumenyuk eng uncontrolled High strength steel eng uncontrolled Laser hybrid welding eng uncontrolled Modified spray arc eng uncontrolled Longitudinal weld eng uncontrolled Pipeline Datei im Netzwerk der BAM verfügbar ("Closed Access") Graue Literatur