미경력자의 일정 교육 후 초음파 검사능력 평가: 탄소강 맞대기 용접부 사례연구

Ultrasonic inspection, one of the most useful inspection method for welding parts, is a technique for making judgement about the defects by the analysis of signals obtained by scanning the objectives. Since the confidence of ultrasonic inspection is influenced by the capability and experience of the inspectors among NDT(Non Destructive Test) methods, unskilled inspectors have less opportunity for ultrasonic inspection on the field. In this study, the RRT (Round Robin Test) method was performed on Carbon Steel butt welds by inspectors who have completed 40 hours of theoretical and practical training required to Level I in SNT-TC-1A and ISO 9712, which are most commonly recognized. As a results of the case study, the length of the defect measured from all the specimens which do not distinguish between the type of defect and the depth of defect by the RRT meet the reliability requirements of ASME BPVC-V Code Sec. XI. Appedix VIII.