Sensitivity Appraisal for Lamellar Tearing of Box-Column of Ultra Thick Plate

J. Ocean Eng. Technol. 2003;17(4):31-36.

극후판 Box-Column의 Lamellar 균열 감수성 평가

노찬승,박창수,김흥주,방한서,이창우

조선대학교 선박해양공학과 대학원,㈜ 미래 이엔씨,조선대학교 선박해양공학과 대학원,조선대학교 선박해양공학과,울산과학대학 기계학부

Keywords: Welded Joint Zone, Lamella Tearing, HAZ, Welding Defect, Crack

핵심용어: 용접부, 열영향부, 용접결함, 균열

Abstract

In case of this thick rolling-steel for a multistory building, a large oil-drilling structure, a large vessel, a bridge and so on, Lamella Tearing around the welded joint zone is the most serious problems. In order to prevent Lamella Tearing, not only is choice of material important, but also the comprehensive investigation for the structural design and the construction. The Lamella Tearing that is a staircase-shape occurs due to the contraction stress to the thickness direction of the plate and has the character that the cracks progress along the elongated inclusion by rolling. In general, because cracks occur at the heat affected zone and around HAZ, it is necessary to establish the safety and the confidence of the welded structure to restrain the welding defect such as Lamella Tearing. The mechanical approaches are the easier and more economical than the approaches of the material and the construction method. In addition, the appropriate welding profile and the optimum welding condition contribute toward the improvement of the productivity and influence on the standardization of the manufacturing technology.