PRACTICAL EXPERIENCE WITH WELDING NEW GENERATION STEEL THOR®115 ASSIGNED FOR POWER INDUSTRY

Abstract

Very popular and highly employed steel grades such as the 9 % Cr CSEF steels are limited in terms of service temperature mainly due to capping their steam oxidation resistance capabilities at temperature levels, required by the drive for efficiency increase. For heat-exchangers manufactured from conventional materials, the formation, growth and spallation of oxide scale on the steam side may eventually impair plant operations and damage other downstream components. To address the requirements of the energy market considering these new requirements, Tenaris developed the Tenaris High Oxidation Resistance (THOR®115) CSEF steel grade. Easy weldability is a key property of steel grades and is decisive whether or not a material is adopted by power plant manufacturers. This paper presents the welding experience of THOR®115 grade assigned to power industry. In contribution, results of non-destructive and destructive tests gained during first steps of welding homogenous welded joints are presented.