lap joint flange Slip On flange welded neck flange, hubbed flange Tread flange,Blind flange socket welding flange lap joint flange Material : 1. Carbon Steel :ASTM A105,20, Q235, 16Mn, ASTM ... neck flange(NF) / hubbed flange 8. loose hubbed flange 9.socket welding flange(SWF) 10. Tread flange 11.flange cover(FC) Blind flange(BF) 12.lap joint flange 13 ...