Technical gazette, Vol. 20 No. 5, 2013.
Original scientific paper
Impact of restrained thermal expansion on NPP Krško primary loop piping
Pino Koc
orcid.org/0000-0002-9565-9478
; University of Ljubljana, Faculty of Mathematics and Physics, Lepi pot 11, 1000 Ljubljana, Slovenia
Miroslav Halilovič
; University of Ljubljana, Faculty of Mechanical Engineering, Aškerčeva 6, 1000 Ljubljana, Slovenia
Boris Štok
; University of Ljubljana, Faculty of Mechanical Engineering, Aškerčeva 6, 1000 Ljubljana, Slovenia
Abstract
Mechanical analyses of the Krško NPP primary system piping subjected to the restrained thermal expansion due to insufficient pipe shim clearances are addressed in the paper. Reduction of clearance between a pipe and respective pipe restraints preclude free thermal expansion of the pipe system during the heat-up, thus causing a rise of excessive contact forces in the pipe - pipe restraint pairs. This results in a development of unfavourable strains and stresses both in pipes and restraints. A series of numerical simulations was performed which demonstrate sufficient strength resistance of the Krško NPP primary piping, while supports are much more susceptible and need careful engineering consideration.
Keywords
finite element method; nuclear power plant; pipe restraint; piping; primary loop; thermal expansion
Hrčak ID:
109801
URI
Publication date:
25.10.2013.
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