Development of 2012 Edition of JSME Code for Design and Construction of Fast Reactors: (1) Overview

Abstract

This paper presents the main features of 2012 Edition of JSME (Japan Society of Mechanical Engineers) Code for Design and Construction of Fast Reactors (JSME FR Code). The first edition of the JSME FR Code was published in 2005 based on the requirements that had been applied to the Japanese Prototype Fast Breeder Reactor Monju. The latest 2012 Edition incorporated 316FR stainless steel and Mod.9Cr-1Mo steel of which application to the Japanese demonstration fast reactors is expected. 316FR is a low-carbon nitrogen added fast reactor grade 316SS which has been developed in Japan. Allowable stresses up to 300,000 hours along with various material properties equations from which they have been derived have been codified. The applicability of the code rules on elevated temperature design to the new materials has been extensively investigated. Focus was on the creep-fatigue interaction evaluation methods, and predictability in long-term regions was carefully demonstrated based on material tests. Various structural tests were also conducted to verify that sufficient margins are maintained for the newly implemented materials. The JSME FR Code will be further upgraded in the 2016 and codes such as fitness-for-service code and leak-before-break evaluation code and a guideline for reliability evaluation of static components will be developed utilizing the System Based Code concept.