Welding of combustion turbine rotors and discs
- Westinghouse Turbine Generator Plant, Charlotte, NC (United States)
- Westinghouse Electric Corp., Orlando, FL (United States)
Weld repair of steam turbine rotors and discs by Westinghouse has been performed successfully and has proven itself in operation for the last 15 years. Since 1978, over 200 low pressure (LP) rotors and discs have been weld repaired using the Gas Tungsten Arc Welding (GTAW) process. This process yields properties equal to or better than the original rotor/disc forging for LP alloys. In 1987, the GTAW process was extended to include repair on high pressure (HP) rotor alloys. Since that time, over 45 high pressure and intermediate pressure (IP) rotors have been successfully weld repaired and returned to service. Recently, to meet the demand for repair of combustion turbine alloys, a development program was initiated to make a step increase in the current LP welding process and filler materials from 100--110 ksi weld metal yield strength (on LP alloys) to 140 ksi needed on many areas of a combustion turbine. The challenge to increase the strength by 30% could not be achieved at the expense of the other critical properties particularly toughness. This paper first reviews the successful LP and HP welding programs which were fundamental building blocks for welding combustion turbines. Secondly, the development and testing of a new filler material for welding combustion turbines is reviewed which demonstrated the ability to achieve approximately 135 ksi yield strength. This new program was implemented on lower stress areas of several production parts which are described in part three. The paper concludes with a summary of possible future work to achieve nominal yield strengths near 145 ksi.
- OSTI ID:
- 234175
- Report Number(s):
- CONF-9411168--; ISBN 0-87171-444-2
- Country of Publication:
- United States
- Language:
- English
Similar Records
Proceedings: Fossil steam turbine disc cracking workshop
Stress corrosion cracking of steam turbine rotors