In recent years, the inspection of pipes is being carried out by using inspection techniques which employ ultrasonic and eddy current testing, endoscope (CCD cameras or optical fiber). Currently, the inspection devices can be performed only a visual check of the pipes. In case of a damage, they cannot be repaired. In such case, the damaged portion has to be excluded or the pipe has to be replaced. The authors develop a laser processing head comprising an optical fiberscope. It is capable of inspection and repair of a pipe with a diameter of 25 mm. The pipes of such size are used in the heat exchanger of a fast breeder reactor. However, pipes with diameters smaller than 25 mm, require a sufficiently small laser processing head that can be inserted into them. The research aims to develop a laser processing head for the inspection and repairing of a pipe with 12 mm diameter. For this purpose, it is used a standing wave type ultrasonic actuator which is orthogonally positioned to the piezoelectric elements. This ultrasonic actuator is developed for implementation in the laser processing head, which is used in inspection and repair of the 12-mm-diameter pipe. In this study, the structure and results of the verification experiments are explained.

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