Numerical and full scale experimental analysis of the transition RPV nozzle to feedwater line DN 425 of a BWR
- Univ. of Stuttgart (Germany). Staatliche Materialpruefungsanstalt
This paper presents a stress analysis of the transition RPV nozzle to feedwater line typical for boiling water reactors (BWR). The loading cases considered are: internal pressure, superimposed bending and stratified flow of different cold water levels. The dimensions of the piping system are D{sub 0} = 475 mm and t = 25 mm. The RPV nozzle was equipped with a thermal sleeve. An additional objective of the investigation was to study the effect of repeated stratified flow as well as alternating bending on cyclic crack growth of a circumferentially oriented crack in the feedwater line. In a final test stage the weakened piping system was loaded at constant internal pressure by a monotonously increasing bending moment up to failure to demonstrate the leak before break behavior. The results consist of stress and strain data; cyclic crack growth rates, comparison to finite element computations and derived effective thermal conductivity values for the annulus between sleeve and nozzle. The experiment as well as extensive recalculations indicated the good protective effect of the thermal sleeve. Maximum stresses are concentrated in the straight pipe section adjacent to the nozzle. The measured cyclic crack growth rates due to repeated stratified flow reached mean da/dN-values of 8 {micro}m per cycle.
- OSTI ID:
- 129217
- Report Number(s):
- CONF-950740-; ISBN 0-7918-1342-8; TRN: IM9550%%585
- Resource Relation:
- Conference: Joint American Society of Mechanical Engineers (ASME)/Japan Society of Mechanical Engineers (JSME) pressure vessels and piping conference, Honolulu, HI (United States), 23-27 Jul 1995; Other Information: PBD: 1995; Related Information: Is Part Of Transient thermal hydraulics, heat transfer, and coupled vessel and piping responses. PVP-Volume 311; Shin, Y.W.; Chang, F.C. [eds.] [Argonne National Lab., IL (United States)]; Madarame, H. [ed.] [Univ. of Tokyo, Tokai, Ibaraki (Japan)]; Moody, F.J. [ed.] [General Electric Co., San Jose, CA (United States)]; Katze, D.; PB: 116 p.
- Country of Publication:
- United States
- Language:
- English
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