Inelastic Analysis of Two Pipelines in the Fast Flux Test Facility

摘要

Several complex pipelines of the Fast Flux Test Facility (FFTF) were evaluated using detailed inelastic analysis because they did not satisfactorily comply with the ASME elastic analysis rules. The purpose of the inelastic analysis is to demonstrate that the piping systems, which operate at elevated temperatures, comly with ASME Code requirements under the loading conditions specified in the Design Specification of each pipeline, using inelastic analysis rules. Two pipelines are discussed, the 8-inch Secondary Hot Leg in the Heat Transport System and the 3-inch/4-inch Primary Hot Leg (Ex-module) in the Closed Loop System. The former is made from type 304SS, operating at 965 exp 0 F (518.3 exp 0 C) and designed for a 20 year life; the latter is made from type 316SS, operating at 1200 exp 0 F (648.9 exp 0 C) and designed for a 10 year life. The MARC general finite element computer program was utilized in the analyses. The pipelines were idealized using the combinations of thin-walled circular closed section beam elements and constant bending 3-node elbow elements. Discussions on the load histograms used, the inelastic strain accumulated, and the effects of creep and fatigue on the lines are given. (ERA citation 04:053218)