| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a turbine moving blade having a fork type blade embedding part suitable for ultrasonic flaw detection. <P>SOLUTION: Assuming a point at which an ultrasonic wave oscillated from an ultrasonic sensor 55 enters a smooth surface 15C as an oscillation reference point P1c, an area on a blade installation surface adjacent to a projecting image of an outer fork 10a onto the blade installation surface 13 as a sensor arranging area D2, a width of the outer fork as a fork width (W3), a distance up to the oscillation reference point from an inflection point P3 of expanding the outer fork as the ultrasonic wave passing depth (H4), a point at which a straight line of contacting with a pinhole of the outer fork by passing through the inflection point from the oscillation reference point, reaches an end surface of the outer fork as an ultrasonic wave arrival point P2c, and a distance up to the oscillation reference point from the ultrasonic wave arrival point as an ultrasonic wave arrival distance (Hc), the sensor arranging area D2 is formed so that a width (W4) in the rotary axis direction satisfies "W4=H4*W3(Hc-H4)", and the smooth surface is arranged so that the oscillation reference point is positioned in the sensor arranging area D2. <P>COPYRIGHT: (C)2012,JPO&INPIT |
