Bolt Breakage Incident for Low-Level Radioactive Waste Container（1) ― Investigation into Cause and Measures ―

Year
2016
Author(s)
Shoko Kakiuchi - Nuclear Fuel Transport Co., Ltd.
Koichi Nakama - Engineering Department, Nuclear Fuel Transport Co., Ltd., 1-1-3, Shiba Daimon, Minato-Ku, Tokyo 105-0012, Japan
Hideki Takatsuki - Engineering Department, Nuclear Fuel Transport Co., Ltd., 1-1-3, Shiba Daimon, Minato-Ku, Tokyo 105-0012, Japan
Yutaka Hirose - Engineering Department, Nuclear Fuel Transport Co., Ltd., 1-1-3, Shiba Daimon, Minato-Ku, Tokyo 105-0012, Japan
Misami Hanate - Engineering Department, Nuclear Fuel Transport Co., Ltd., 1-1-3, Shiba Daimon, Minato-Ku, Tokyo 105-0012, Japan
File Attachment
F1036.pdf607.16 KB
Abstract
The Nuclear Fuel Transport Co., Ltd. (“NFT”) found that lid anchor bolts (“lid bolts”) onLow-Level Radioactive Waste (“LLW”) containers failed during inspection and/or maintenance.LLW transport was suspended temporarily to verify LLW container safety after this incident.First, NFT went immediately to work to determine the cause and formulate measures to prevent any such recurrence. As a result, the cause was identified as “delayed fracture.” In addition, as for the recurrence prevention measures, we made the assessment that changing to a lower strength class of lid bolt would be effective. NFT resumed LLW transport using LLW containers for which recurrence prevention measures had been adopted.