Acoustic emission monitoring for crack growth in headers

Technical Report · Mon Jul 01 04:00:00 EDT 1996

OSTI ID:401930

Morgan, B C ^[1]; Tilley, R ^[2]

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1. VECTRA Technologies, Inc., San Ramon, CA (United States)
2. Electric Power Research Institute, Palo Alto, CA (United States)

EPRI and Pacific Gas & Electric Company have cooperated in a program to investigate use of acoustic emission monitoring for detection of cracking in fossil plant high energy superheater outlet headers. These chrome moly headers have been shown to be susceptible to creep damage and thermal fatigue from elevated temperature operation. These mechanisms have initiated and grown cracks in bore hole tube ligaments and stub tube-to-header welds. This program has field monitored a cracked header. Those results correlated acoustic emission signal generation to damage found at stub tube-to-header welds. The program also conducted laboratory testing to generate ligament cracking. These grown ligament cracks also produced detectable acoustic emission. Utilizing these results, EPRI guidelines are currently being generated for applying acoustic emission monitoring to high energy headers. The objective is to provide a means of detecting and assessing crack growth as part of condition monitoring.

• Research Organization: Electric Power Research Inst., Palo Alto, CA (United States); Baltimore Gas and Electric Co., MD (United States)
• OSTI ID: 401930
• Report Number(s): EPRI-TR--106753; CONF-960719--
• Country of Publication: United States
• Language: English

Related Subjects

20 FOSSIL-FUELED POWER PLANTS
42 ENGINEERING
ACOUSTIC EMISSION TESTING
CRACK PROPAGATION
FOSSIL-FUEL POWER PLANTS
MAINTENANCE
MONITORING
SUPERHEATERS
WELDED JOINTS