| 摘要 |
PROBLEM TO BE SOLVED: To provide a lifetime evaluation method for the simple and quick evaluation of the depth of cracks in a furnace wall tube, and so on of a boiler, and so on, with a higher precision. SOLUTION: The lifetime evaluation method enables the measurement of a crack evaluation item consisting of one of a crack length distribution, a crack width distribution and a crack area ratio of a surface of a test object or their combination by image processing, and estimates the crack depth out of the measured crack evaluation item based on correlations between the preset crack evaluation item and the crack depth. The plurality of correlations have been preset as relational expressions of the crack evaluation item and the crack depth. A relational expression, which has been selected out of the plurality of relational expressions based on a working environment of the test object and environmental factors including a temperature condition, and so on, is used to estimate the crack depth out of the crack evaluation item detected by image processing out of a photographed image of a surface of the crack. COPYRIGHT: (C)2009,JPO&INPIT |
