Board wave ultrasonic crack inspect manner and device

摘要

PURPOSE: To provide a method and an apparatus for ultrasonic flaw detecting with plate waves in which the flaw erroneous detection and missing can be reduced even if a material to be flaw detected is moved in a zigzag manner and its present position can be accurately obtained. ;CONSTITUTION: A flaw detection signal received by a tire probe 11 is converted to a digital signal, applied to a mapping memory 7, and converted to a two-dimensional image based on a pulse signal applied from a pulse timing controller 3. The two-dimensional flaw detection signal is converted to a two-dimensional flaw detection image by a CPU 9, and stored in an image memory 8. The CPU 9 binarizes the image stored in the memory 8 by using previously decided threshold value, and discriminates the image due to the random reflection near the probe and the image of the edge of the material to be flaw detected from the image of the signal except it. The images of the former two thus discriminated are temporarily removed from the two-dimensional image, and if the image exists after the removal, the image is judges as being according to the flaw.;COPYRIGHT: (C)1996,JPO