High strength seamless line pipes up to grade X100

The development and improvement of high-strength steel grades up to grade X100 with good toughness and sour service properties as well as welding performance becomes more and more important due to enhanced material and design requirements. Over the last years Vallourec & Mannesmann Tubes and Salzgitter Mannesmann Forschung have developed new high strength steels up to grade X90 or even X100. Seamless quenched and tempered pipes with wall thickness up to 38mm of these steels exhibited good toughness and sour service properties. Welding tests on grade X70 material were very promising, showing a good weldability. Further welding tests are performed at the moment on X80 and X90 pipe material.