Systems and methods for heat treating closed shape workpieces are provided. In one example implementation, a method can include imparting relative motion of the closed shape workpiece such that the perimeter surface of the closed shape workpiece is moved relative to the lamp heat source from a first position where a first portion of the closed shape workpiece is presented to the lamp heat source to a second position where a second portion of the closed shape workpiece is presented to the lamp heat source. The method can include emitting lamp heat onto the perimeter surface of the closed shape workpiece from the lamp heat source during imparting of relative motion of the closed shape workpiece. The method can include implementing a flux control procedure during emitting of lamp heat onto the perimeter surface of the closed shape workpiece.