균열 보수 락을 이용한 대형 주철 균열재의 냉간 체결 방법에 관한 연구
Abstract
Cracks in large cast iron components are often repaired by cold welding repair. However, this method is often unsuccessful owing to improper pre- and post-heat treatment conditions. In this study, a mechanical joining method using crack repair locks is proposed as a crack repair method for large cast iron components. The aspect ratio of the height to the width in the FEA model for crack repair is 0.95. The structural analytical error of the structural strength test using the proposed crack repair model is 4.8%. The optimization results for joint efficiency of the crack repair component indicate 90%. However, the experimental joint efficiency of crack repair components ranged from 17.7% to 30% owing to the realistic machining conditions of the crack repair site. Therefore, to achieve a high joint efficiency for crack repair components using crack repair locks, the spacing between the crack repair locks must be minimized according to field conditions.
Keywords:
Cracked cast iron component, Cold repair welding, Crack repair lock, Stress concentration factor, Crack repair model, Joint efficiency of crack repair modelReferences
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Ph.D. Candidate in the Department of Mechanical-Computer-Industrial Engineering, Graduate School, Kangwon National University. His research interest is Mechanical Behavior of Materials.
E-mail: cy123@kangwon.ac.kr
Professor in the Division of Mechanical Design Engineering, Kangwon National University. His research interest is Mechanical Behavior of Materials.
E-mail: sscho394@kangwon.ac.kr