| 摘要 |
PROBLEM TO BE SOLVED: To make the detection of a crack easy and to improve the reliability of inspection by filling up a furnace wall pipe with a liquid, and putting a probe on an opposite side to an attached metal fitting welded part with the liquid imposed between them to carry out ultrasonic flaw detection. SOLUTION: In the case of inspecting the thermal fatigue crack of the welded part 3 of metal fittings 2 attached to a furnace wall pipe 1, the inside of the furnace wall pipe 1 is filled up with water 7. An inclination type probe 8 is put on the opposite side to the welded part 3 with the water 7 imposed between them, namely from the inner side of the furnace, and connected to an ultrasonic flaw detector for carrying out ultrasonic flaw detection by a gradient method. The ultrasonic wave propagates from the furnace wall pipe 1 to the water 7, the furnace wall pipe 1 and an attached matter welded part 3 being an object for inspection without much attenuation. Since a reflection wave in the case of a crack 4 propagates similarly, the ultrasonic flaw detection can be carried out with excellent reliability. The probe can be easily brought into contact with spot to be inspected because of its inside arrangement. Thus the inspection can be easily carried out, and moreover, can dispense with the removal and restoration of a heat insulating material, refractory material and a casing, and the cost and time can be saved. |
