Thermal processing of closed shape workpieces

A system for thermally treating a cylindrical workpiece, the system comprising:

• a vessel configured to impart rotational motion for the cylindrical workpiece;
• a lamp heat source operable to focus lamp heat onto a portion of a perimeter surface of the cylindrical workpiece;
• a control system operable to:
• control the vessel to initiate and ramp up the rotational motion of the cylindrical workpiece to a desired rotational speed;
• ignite the lamp heat source after the desired rotational speed is achieved;
• and
• control the vessel to move the perimeter surface of the cylindrical workpiece relative to the lamp heat source from a first position where a first portion of a perimeter surface of a the closed shape cylindrical workpiece is presented to the lamp heat source to a second position where a second portion of the perimeter surface of the closed shape cylindrical workpiece is presented to the lamp heat source, the second portion being located proximate to the first portion, at least 90% of the perimeter surface of the closed shape cylindrical workpiece being located between the first portion and the second portion,
• wherein the control system comprises a temperature sensor configured to measure a temperature of the perimeter surface of the cylindrical workpiece, the temperature sensor comprises a thermal radiometer positioned such that a field of view associated with the temperature sensor is directed to a portion of the cylindrical workpiece after it has rotated through light from the lamp heat source and such that the field of view does not include light from the lamp heat source.