Development of a laser processing head using a composite-type optical fiberscope to inspect and repair 1-inch heat exchanger pipes

A composite-type optical fiberscope was combined with a laser processing head to repair heat exchange pipes of Fast Breeder Reactor (FBR). The head can rotate axially and move back and forth longitudinally in the 1-inch pipes. The property of fiberscope and the motion of the head can successfully observe the pipe's inner surface to find the cracks which should be repaired by laser welding. The project, which aims for developing the integrated system of inspection and repair, proposes an effective cost reduction for maintenance of FBRs by extension of the head exchanger's lifetime. This report describes the outline of the laser processing head and the basic performance. (author)