Select 2 ISA 80 × 50 × 6 mm. A g = 2 × 746 = 1492 mm2 An = 1492–2 × 18 × 6 = 1492–216 =1276 mm 2 <1333 mm2 NG Select 2 ISA90 × 60×6 mm.
確定! 回上一頁