Advances in flaw evaluation procedures and acceptance criteria for reactor piping

Conference · Wed Jan 01 04:00:00 EST 1986 · Trans. Am. Nucl. Soc.; (United States)

OSTI ID:6499113

Gamble, R M; Zahoor, A; Norris, D M

During the past several years, intergranular stress corrosion cracks (IGSCC) have been detected in stainless steel piping in boiling water reactors (BWRs) and have resulted in an increased number of flaw evaluations. To reduce the outage time associated with evaluating IGSCC, various research and ASME code groups have spent significant effort to provide utility personnel with efficient means to detect, classify, and size flaws, and to determine suitability for return to service for flawed stainless steel piping. One of the several nondestructive evaluation technologies that has received considerable attention is fracture mechanics, the discipline that considers the failure of flawed material. Fracture mechanics can be used to answer two key questions concerning return to service of flawed pipe: (a) what is the largest flaw size that can be returned to service and still maintain adequate safety margins at the applied loads, and (b) how much operating time remains before the crack reaches the largest allowable size. The purpose of this paper is to provide an overview of the recently developed ASME code Section XI flaw size evaluation procedure and acceptance criteria for stainless steel piping and their application by BWR owners to efficiently determine if flaws found by nondestructive examination are acceptable for continued service.

• Research Organization: NOVETECH Corp., Rockville, MD
• OSTI ID: 6499113
• Report Number(s): CONF-860610-
• Conference Information: Journal Name: Trans. Am. Nucl. Soc.; (United States) Journal Volume: 52
• Country of Publication: United States
• Language: English

Related Subjects

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS
210100* -- Power Reactors
Nonbreeding
Light-Water Moderated
Boiling Water Cooled
42 ENGINEERING
420500 -- Engineering-- Materials Testing
ALLOYS
BWR TYPE REACTORS
CHEMICAL REACTIONS
CHROMIUM ALLOYS
CLASSIFICATION
COOLING SYSTEMS
CORROSION
CORROSION RESISTANT ALLOYS
CRACK PROPAGATION
CRACKS
DEFECTS
DESIGN
ENERGY SYSTEMS
FAILURES
FRACTURE MECHANICS
INSPECTION
INTERGRANULAR CORROSION
IRON ALLOYS
IRON BASE ALLOYS
JOINTS
MATERIALS TESTING
MECHANICS
NONDESTRUCTIVE TESTING
PIPES
PRIMARY COOLANT CIRCUITS
REACTOR COMPONENTS
REACTOR COOLING SYSTEMS
REACTORS
REPAIR
STAINLESS STEELS
STEELS
STRESS CORROSION
TESTING
WATER COOLED REACTORS
WATER MODERATED REACTORS
WELDED JOINTS