Automated Welding of Turbine Blades

Abstract

The welding of superalloys has been regarded, generally, as an art requiring the highest degree of welder skill and discipline. These highly alloyed materials are prone to micro-cracking and, in some cases, even the best welders cannot achieve satisfactory results. Now, however, advances in automation technology have made it possible to program precisely the complex airfoil shapes and the welding parameters. Consequently, turbine blades can be welded in a repeatable manner, with a minimum of heat input, resulting in better metallurgical quality both in the base metal and the weld deposit. The application of this technology to the automated welding of high-pressure compressor turbine blade tips and the refurbishment of low-pressure turbine blade shrouds are presented in this paper.