China En1092 ASME B16.5 BS4504 DIN2501 DIN2673 Pn10 Pn16 S235jr S275jr A105 Mild Steel Plate Back Ring Carbon Steel Plate Flange, Find details about China Flange, Electric from En1092 ASME B16.5 BS4504 DIN2501 DIN2673 Pn10 Pn16 S235jr S275jr A105 Mild Steel Plate Back Ring Carbon Steel Plate Flange