Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

A specialized program for life extension of HP-IP steam turbine rotors

Conference ·
OSTI ID:549994
;  [1]
  1. Reinhart and Associates, Inc., Austin, TX (United States)
Significant cracking in the HP stages of two HP-IP steam turbine rotors required the development of programs to assess the impact of the cracking observed at the seal land surfaces on the integrity of the rotor under daily hot starts. Originally designed for base-load operation, the units ar constrained in their operation by design (minimal steam bypass capability to the condenser) and environmental concerns (noise abatement). Combined with daily starts, these operational constraints subject the HP-IP steam turbine rotors to excessive thermal stresses. A program of analysis, inspection, and plant operation modification has been developed to continue operation of the unit for the least overall cost. This paper covers analysis of the cracking, strategies for its control, and innovative nondestructive ultrasonic inspection techniques used to monitor the condition of the rotor. To minimize inspection time, a unique, computer-based ultrasonic boreside scanning system was used to examine the blade attachment areas with the rotors in place. Five boreside inspections have been conducted with an expansion to include a portion of the IP stages. The overall program has extended by ten years the useful operating life of two turbine units previously recommended for replacement or repair. The cost savings to the utility have been considerable because no replacement rotors were required, repair costs were reduced, and the in-place inspection reduced downtime and disassembly costs. Results of the four-year program are presented in this paper.
OSTI ID:
549994
Report Number(s):
CONF-961006--; ISBN 0-7918-1796-2
Country of Publication:
United States
Language:
English

Similar Records

Main steam inlet sleeves on steam turbines: External ultrasonic test and external sleeve replacement (closed HP-IP casing)
Conference · Mon Dec 30 23:00:00 EST 1996 · OSTI ID:549971

Independent life extension of a steam turbine rotor
Conference · Mon Dec 30 23:00:00 EST 1996 · OSTI ID:549995

TRIAD; A decision support system for evaluating turbine rotor replacement decisions
Conference · Mon Dec 31 23:00:00 EST 1990 · Proceedings of the American Power Conference; (United States) · OSTI ID:5136084