SIGRID –THE FIRST PART OF THE RENEWAL OF THE SWEDISH TRANSPORT SYSTEM

After more than 25 years of successful operation Swedish Nuclear Fuel and Waste Management Company (SKB) late 2010 took the first step of the renewal of the transport fleet in Sweden by signing a new building contract for a new INF-3 ship. The renewal programme will continue until 2020 when SKB in addition to the new ship, also expects to have replaced also the transport casks for transport of spent fuel and the terminal vehicles which are used for the local transports to and from the harbours. In writing moment the new building project only have a few weeks until delivery and the start of operation of the ship, named Sigrid, is expected in fall 2013. SKB has in close cooperation with the building yard, the Swedish Transport Agency and the Classification society designed the INF-3 ship to fulfil the needs of SKB and the Swedish Nuclear Power Plants for the next 30 years. The ship has an extensive and optimized radiation shield to minimize the yearly dose to the crew of the ship. The radiation shield consists of approximately 700 tonnes of concrete, steel and polyethylene. To both the concrete and polyethylene boron has been added in order to improve the shielding. In addition to the extensive and heavy radiation shield the ship for example has an extra high freeboard height to increase security. To achieve these two key (radiation protection and security) features and still fulfil the stability criteria for the ship have been a great challenge for the Naval Architects. The paper will give a general overview of the key features of the new Swedish INF-3 ship. The paper will include a description of the radiation shield on the ship and an overview on how security issues have been considered in the design of ship.