%A"Henry, P T [Canadian General Electric Co. Ltd., Peterborough, ON (Canada)]" %D1996 %I; Canadian Nuclear Society, Toronto, ON (Canada) %2 %J[] %K21 NUCLEAR POWER REACTORS AND ASSOCIATED PLANTS, BRUCE-1 REACTOR, FUEL MANAGEMENT, REACTOR SAFETY, FUEL CHANNELS, CRACKS, DESIGN, HYDRIDATION, LOSS OF COOLANT, MODIFICATIONS, PRIMARY COOLANT CIRCUITS, REACTOR FUELING, TRANSIENTS, ZIRCONIUM BASE ALLOYS %PMedium: ED; Size: pp. 65-74 %TFuel string supporting shield plug (f3sp) for Ontario Hydro - Bruce NGSA %XA reactor `power pulse` problem was identified for the Ontario Hydro Bruce generating stations. On a postulated inlet header break, the fuel strings in a large number of channels could relocate toward the upstream end, resulting in a power pulse. The solution adopted for Bruce GSA is to change the direction of fuelling, from against the flow, to fuelling with the flow. In this revised fuelling scheme, given a postulated inlet header failure, the fuel bundle with the highest burnup would relocate into the reactor core and introduce a negative reactivity during the accident. However, this fuelling configuration results in a highly irradiated fuel bundle residing in the most downstream position against the latch. The latch supports only the outer ring of elements, not the end plate. A resulting high stress on the end plate coupled with high levels of hydrogen and deuterium may result in Zr hydride assisted cracking in the end plate during hot shutdown conditions. (In fuelling against flow, this is not a problem, since the latch supported bundle is not irradiated and has only low levels of hydrogen and deuterium.) A fuel string supporting shield plug (f3sp) which supports the bundle end plate has been developed as a solution to the fuel bundle end plate cracking problem. It would replace the existing outlet shield plug in all channels. This paper will describe the f3sp design, associated fuel handling, operation and qualification for reactor use. (author). 8 figs. %0Conference %NINIS-CA-0052; CONF-9605298-;Other: ON: DE98605472; ISBN 0-919784-43-7; TRN: CA9700725076129 %1 %CCanada %Rhttps://doi.org/ Other: ON: DE98605472; ISBN 0-919784-43-7; TRN: CA9700725076129 INIS %GEnglish