This is the present state of the calandria assembly at CGE's Peterborough plant. The completed end wall units are joined by the dump slot. Assembly is being performed in a huge positioner to enable as many welds as possible to be performed in the horizontal plane

No metalworking operation plays a larger part in the manufacture of the NPD-2 nuclear power station than welding. What is more, much of the welding employed in 'the construction of the power station has been the subject of preproduction research of both fundamental and practical nature. Examples are found in the manufacture of the reactor vessel and the Zirconium alloy fuel bundles by the Civilian Atomic Power Department of Canadian General Electric Company, Peterborough, and in the manufacture of the heat exchanger by Babcock- Wilcox & Goldie-McCulloch, Gait. The largest welding undertaking is in the fabrication of the reactor core. This unit, called the calandria, consists of a large aluminum assembly of horizontal cylindrical form. The diagram shows the general arrangement of the calandria with the moderator dump tank added.