The Manufacture, Quality Control and Performance of KANUPP Fuel

Abstract

KANUPP is a 137 MWe CANDU reactor. The fuel material is high density sintered pellets (95 to 97% T.D.) of natural UO₂ cladded in Zr-4 sheaths.

The reactor grade UO₂ powder is precompacted, granulated and blended with 0.2% Zinc-Stearate and compacted into green pellets of about 50% of theoretical density. The green pellets are sintered at about 1650 degree centigrade in a reducing atmosphere of cracked ammonia. Sintered pellets are finished by centreless grinding, culled, and loaded into Zr-4 tubes for end closures. The welded elements are assembled into a fuel bundle. Quality Control and Quality Assurance procedures are stringently adopted during all stages of manufacturing.

The entire core of KANUPP now consists of locally manufactured fuel. Several bundles have already achieved the designed burnup (i.e. 8650 MWD/TU) of KANUPP. There has never been any failure during irradiation of our manufactured fuel.