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

Acoustic emission monitoring of steam turbines. Final report

Technical Report ·
OSTI ID:6192196

Experience over several years with on-line monitoring of steam turbines, supported by relevant laboratory studies, has led to a clearer understanding of the conditions under which acoustic emission (AE) due to turbine shaft cracking can be detected. To overcome problems associated with the noisy environment, efforts have been directed at improving the AE signal discrimination capabilities of the monitoring electronics. These efforts have been guided by extensive measurements of the amplitude, frequency and time dependence of normal turbine noises in a variety of operating conditions. Similar measurements have been made in the laboratory to determine the characteristics of AE due to crack growth in rotor steels with several loading conditions and temperatures. Along with determinations of the attenuation and wave propagation characteristics of simulated AE in the rotor shafts, these measurements have permitted estimates of the detectability of AE due to crack growth under various conditions, should it occur. An essential part of the proposed monitoring will be determining the source locations and characteristics of ''normal'' operating noise and developing time histories of these sources so that when ''abnormal'' crack growth AE occurs, it will be recognized. The time histories of the ''normal'' operating noises may also reveal other potentially damaging conditions such as lubricating oil contamination, bearing wear, out-of-balance condition, loose turbine disks, blade cracking or rubbing and impingement of exfoliation particles or water droplets, each of which is known or expected to have a characteristic acoustic signature. 17 refs., 23 figs., 8 tabs.

Research Organization:
Rockwell International Corp., Canoga Park, CA (USA). Rocketdyne Div.; Rockwell International Corp., Thousand Oaks, CA (USA). Science Center
OSTI ID:
6192196
Report Number(s):
EPRI-CS-4427; ON: TI86920171
Country of Publication:
United States
Language:
English