| 摘要 |
PROBLEM TO BE SOLVED: To provide an in-pipe insertion immersion type ultrasonic flaw detector capable of moving inside the piping by water flow at a predetermined speed.SOLUTION: An in-pipe insertion immersion type ultrasonic flaw detector is provided with a propulsion device. The propulsion device includes: a fixed boss fitted and fixed to a flexible shaft; a movable boss slidably fitted to the flexible shaft; and both end parts fixed to the fixed boss and the movable boss, while the movable boss includes: a plurality of wires having a central part capable of projecting to the radial outside of the flexible shaft according as the movable boss approaches the fixed boss; and a pressure receiving member having an inner peripheral part surrounding the flexible shaft, having an outer peripheral part fixed to the central part of the wire, and capable of increasing a pressure receiving area receiving water flow as a result of the projection of the central part of the wire toward the radial outside of the flexible shaft. |
