In 1959 Aluminium Corporation installed a 800HP Robertson 60" wide 2Hi-reversing hot mill to break down 650lb slabs into sheet & coil. This replaced the 3 Hi Krupp Mill previously used as the hot mill. In this photograph it appears that the main reduction gearbox has not yet been installed but the AC driven MG(motor-generator) set is in place to generate the DC required to feed the mill. The AC generator set had a large flywheel to accumulate power that was drawn down when the mill was in full operation. If the mill operator tried to draw too much power with multiple large reductions the MG set would slow down and ring an alarm bell to warn the hot mill operator he was a risk of stalling the mill.