An oven for curing ultraviolet curable ink on cylindrical objects consists of an assembly of two pairs of elongated ultraviolet lamps with respective reflectors for directing the radiation of the respective pairs of lamps toward the path taken by the objects to be cooled. The assembly is rotatable to move either of the pair of lamps into operative curing position and to enable maintenance on the other two lamps or the lamp power supplies at a convenient time as when other maintenance is required rather than force immediate shutdown of the decorating/printing and curing line. Air flow paths are provided to cool the lamps and reflectors during high power operation and to enable the lamp to stay hot during low power operation. A plurality of spindles which carry the cans to be cured are fixed on the pins of a pin chain and move over a wire brush type rack to cause the spindles and then the cans on the spindles to rotate as they move under and along the length of the lamps.