METHOD OF EXECUTING WATER JET PEENING

摘要

PROBLEM TO BE SOLVED: To provide a method of executing water jet peening capable of shortening a time required for executing water jet peening.SOLUTION: A top head 18 forming a top head is provided with a plurality of control rod drive mechanism (CRDM) penetration pipes 19 arranged in a square grid-like pattern. The CRDM penetration pipes 19 are joined with one another by a tube support 20 member disposed among them. The top head 18 is placed on a tank 17 and water 31 is filled in an inner region 42 of the tank 17 and the top head 18. A travel apparatus 8 moves a nozzle lifting/lowering apparatus 5 to a predetermined location and a lifting/lowering mechanism 4 is operated to lift a jet nozzle 1 above the tube support member 20 in the neighboring four CRDM penetration pipes 19. An ejection outlet of the jet nozzle 1 is directed to a weld between one of the CRDM penetration pipes 19 and the top head 18, and a water jet is ejected to start WJP. A nozzle turning mechanism 3 turns the jet nozzle 1, and WJP is executed sequentially to the four CRDM penetration pipes.