断面サイズ、壁厚、鋼種、接続および設計荷重が該当するエンジニアリング要件を満たしていれば、多くの構造用途に使用できます。 The tube itself should not be selected solely by shape.
3. Q355Bの代わりにQ235Bを使用できますか?
自動的ではありません。 Q235B and Q355B have different specified mechanical properties. If the engineering design requires the higher strength of Q355B, replacing it with Q235B without recalculating the structure is not appropriate.
はい。 Hot-dip galvanized surface treatment can be supplied according to the agreed specification. For outdoor projects, the required galvanizing standard or coating requirement should be stated in the purchase order.