Influence on properties of base metal after elimination of lifting-lug member in a dissimilar welding between steel base and steel lifting lug
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The increasing demands of lifting lugs can be attributed to the rapid advancement of shipbuilding and offshore-structure production technologies and an exponential increase in the size of the block units of ship structures. Therefore, to ensure safety during the transportation and turnover of large blocks, it is important to determine the structural integrity and position of lifting lugs. However, because the manufacturing cost and availability of lugs are important considerations, low cost and easily obtainable steel compositions of grades different from those of the blocks are often used as alternatives. The purpose of this study is to investigate the effect of a lifting-lug metal on the physical properties of a base metal in a dissimilar welding between the base metal and lifting lug. The effect was evaluated by observing the metal microstructures and determining the hardness and dilution values on the crosssectional surface of the lifting lug. According to the results of the metal microstructures, impact, hardness, and emission spectrochemical analysis at the surface from where the lug was removed confirmed that the chemical composition of the lifting-lug metal did not influence the physical properties of the base metal.
Abstract
The increasing demands of lifting lugs can be attributed to the rapid advancement of shipbuilding and offshore-structure production technologies and an exponential increase in the size of the block units of ship structures. Therefore, to ensure safety during the transportation and turnover of large blocks, it is important to determine the structural integrity and position of lifting lugs. However, because the manufacturing cost and availability of lugs are important considerations, low cost and easily obtainable steel compositions of grades different from those of the blocks are often used as alternatives. The purpose of this study is to investigate the effect of a lifting-lug metal on the physical properties of a base metal in a dissimilar welding between the base metal and lifting lug. The effect was evaluated by observing the metal microstructures and determining the hardness and dilution values on the crosssectional surface of the lifting lug. According to the results of the metal microstructures, impact, hardness, and emission spectrochemical analysis at the surface from where the lug was removed confirmed that the chemical composition of the lifting-lug metal did not influence the physical properties of the base metal.
참고문헌 (16)
- Adams, "Colling rates and peak temperatures in fusion welding", Weld. J. Res, (supplement), pp.210~215 (1958)
- 안규백, "극저온용 강재 용접부 파괴인성 파라메타의 상관성 규명", 대한용접접합학회지, 35(3), pp.82~87 (2017), 대한용접접합학회[DOI]
- ASME-BTHe1; Design of Below-The-Hook Lifting Devices, "American Society of Mechanical Engineers", ASME, ~ (2008)
- Gunaraj, V., "Prediction and comparison of the area of the heataffected zone for the bead-on-plate and bead-on-joint in submerged arc welding of pipes", J. Mater. Process. Technol, 95(1-3), pp.246~261 (1999)[DOI]
- Ham, Juh-Hyeok, "Development of the design system for the lifting lug structure", J. Soc. Naval Architect. Korea, 38(1), pp.86~98 (2001)
- 함주혁, "선박블록 탑재용 러그구조의 파라메트릭 설계 고찰", 한국해양공학회지, 25(2), pp.101~107 (2011), 한국해양공학회
- 함주혁, "하이브리드 구조설계 시스템을 이용한 선박블록 탑재용 러그구조 고찰", 한국해양공학회지, 23(2), pp.104~109 (2009), 한국해양공학회
- Hoshino, Manabu, "Development of super-9%Ni steel plates with superior low-temperature toughness for LNG storage tanks", Nippon Steel Tech. Rep, 90, pp.20~24 (2004)
- 김상일, "리프팅 러그 재사용율 제고를 위한 설계", 대한조선학회 논문집, 40(4), pp.9~65 (2003), 대한조선학회
- 김상일, "블록 리프팅 시 Hopper Tank부 균열 발생 가능성 검토를 위한 구조해석", 한국해양공학회지, 20(1), pp.16~19 (2006), 한국해양공학회
- Kim, Oi-Hyun, "Reliability assessment of ship longitudinal strength for the rational ship structural design", J. Ocean Eng. Technol, 12(4), pp.8~15 (1998)
- Kim, Gwang-Soo, "Study on the formation and prevention of weld defect on the surface ground after removing the weld for lifting lug", Summer Conference of the Korean Welding and Joining Society 1996 (1996)
- Nouri, M., "Effect of welding parameters on dilution and weld bead geometry in cladding", J. Mater. Sci. Technol, 23(6), pp.817~822 (2007)
- Om, Hari, "Effect of heat input on dilution and heat affected zone in submerged arc welding process", Sadhaba _Acad. Proc. Eng. Sci, 38(6), pp.1369~1391 (2013)
- Park, Seung Hwan C., "Microstructural evolution and its effect on Hall-Petch relationship in friction stir welding of thixomolded Mg alloy AZ91D", J. Mater. Sci, 38(21), pp.4379~4383 (2003)
- "Welding handbook vol. 1", pp.95~100 (1991), American Welding Society