| 摘要 |
PURPOSE:To eliminate the mechanical alteration of the replacement or mount dimension of a sensor unit, by calculating the interval between a material to be subjected to flaw detection and a flaw detection probe as the function of the outer diameter dimension of the material to be subjected to flaw detection and correcting the output of the flaw detection probe on the basis of interval correction coefficient. CONSTITUTION:The interval G between the surface of a part to be subject to flaw detection and the valley part of a V-shaped roll 12 is different according to the outer diameter phiof the material 10 to be subjected to flaw detection. The interval G is the product of the function F1(theta) of the open angle (the angle of the V-shaped roll) of the V-shaped roll 12 and the outer diameter phi of the material 10 to be subjected to flaw detection and a horizontal interval D is the product of the function F2(theta) of the V-shaped roll angle theta and the outer diameter phi of the material 10 to be subjected to flaw detection. Therefore, the interval G and the horizontal interval D are different according to the V-shaped roll angle theta and, as the angle theta becomes larger, the difference of the interval G due to the change in the outer diameter becomes smaller and the change of the horizontal interval D also becomes smaller. In order to correct the change in the sensitivity of a sensor caused by the change in the intervals, the interval between the material to be subjected to flaw detection and a flaw detection probe, when the V-shaped roll is contacted with the surface of the material to be subjected to flaw detection, is calculated as the function of the outer diameter function of the material to be subjected to flaw detection and interval correction coefficient is guided from the correlation of the intervals and flaw detection sensitivity and the output of the flaw detection probe is corrected on the basis of said coefficient. |
