Operation and maintenance experience from the HTTR database

Abstract

The Japan Atomic Energy Agency has been establishing a database of operation and maintenance experience for the High Temperature Engineering Test Reactor. The objective of this database is to share information from operation and maintenance experience and make use of the knowledge gained in the design, construction, and operation of future High Temperature Gas-cooled Reactors (HTGRs). Between 1997 and 2012, more than 1000 events have been registered in this database system. This paper describes trends in operation and maintenance events recorded in this database, including experience gained from the Great East Japan Earthquake. The paper also identifies the following significant items that are expected to be useful in the design of future HTGRs: (1) performance degradation of helium gas compressors, (2) malfunction of the reserved shutdown system in the reactivity control system, (3) problems with emergency gas turbine generators, and (4) consequences of the Great East Japan Earthquake.

Graded Approach Establishment for the HTGR Maintenance Activities Using Modified Fuzzy FMEA & Expert Judgement Methodology

“…Technology developer countries such as Japan developing future commercial HTGR by using their available High Temperature Engineering Test Reactor (HTTR). Various deterministic and probabilistic data to define the maintenance strategy have been collecting such as reported by Shimazaki et al [8], Umeda et al [9], and Shimizu et al [10]. Data exchange to improve the understanding as part of maintenance preparation is also ongoing between some countries such as what has been done between JAEA and INET [11].…”