Development of low-temperature high-strength integral steel castings for offshore construction by casting process engineering
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In casting steels for offshore construction, manufacturing integral casted structures to prevent fatiguecracks in the stress raisers is superior to using welded structures. Here, mold design and casting analysis were conductedfor integral casting steel. The laminar flow of molten metal was analyzed and distributions of hot spots and porositieswere studied. A prototype was subsequently produced, and air vents were designed to improve the surface defects causedby the release of gas. A radiographic test revealed no internal defects inside the casted steel. Evaluating the chemicaland mechanical properties of specimens sampled from the product revealed that target values were quantitativelysatisfied. To assess weldability in consideration of repair welding, the product was machined with grooves and welded,after which the mechanical properties of hardness as well as tensile, impact, and bending strengths were evaluated. Nosubstantive differences were found in the mechanical properties before and after welding.
Abstract
In casting steels for offshore construction, manufacturing integral casted structures to prevent fatiguecracks in the stress raisers is superior to using welded structures. Here, mold design and casting analysis were conductedfor integral casting steel. The laminar flow of molten metal was analyzed and distributions of hot spots and porositieswere studied. A prototype was subsequently produced, and air vents were designed to improve the surface defects causedby the release of gas. A radiographic test revealed no internal defects inside the casted steel. Evaluating the chemicaland mechanical properties of specimens sampled from the product revealed that target values were quantitativelysatisfied. To assess weldability in consideration of repair welding, the product was machined with grooves and welded,after which the mechanical properties of hardness as well as tensile, impact, and bending strengths were evaluated. Nosubstantive differences were found in the mechanical properties before and after welding.
참고문헌 (12)
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