Improvements to the Torness fuel route

The twin Advanced Gas-cooled Reactor power station at Torness first generated electricity in 1988. The reactors were designed for on-load refuelling at a reactor pressure of about 40 bar. However, during commissioning of the fuel handling, storage and dismantling equipment in 1989, deficiencies were identified which restricted the station to refuelling with the reactors shutdown and pressurised. In addition, constraints were imposed on plant, which included measures such as manual isolation of certain plant drive motors when not in use, to prevent any possibility of their operation except in the correct operating sequence. The specification, design and implementation of modifications to Torness fuel route to remove these operational constraints are described. (author)