The Use of Glass Reinforced Plastic as a Flask Energy Absorbing Material

Irradiated fuel transport flasks arc designed to survive impact and fire accidents without significant leakage of contents. The impact standards laid down by the IAEA include a drop test from a height of 9 metres, in the most damaging attitude, onto a flat unyielding target. This requirement leads to the incorporation of energy absorption features for impact protection. Such features may be integral with the fla!lk body and/or lid, as seen on the CEGB's Magnox MkM2 and AGR Mkt\\2 flasks. Altemativcly, it may be operationally more convenient to have removeable energy absorbers, as on most I.WR flasks and the CEGB's AGR MkA I flask. This paper is concerned with the design of removeable energy absorbers and the materials which may be used in their construction. In order to address the design issues, a notional cylindrical flask of 10 tonne mass is considered. To allow a design margin, and to cater for all future requirements and posible changes in regulations etc., the drop height considered is increased to 36 metres.