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      Butt welding flange with neck refers to a kind of flange with taper neck and butt welding with cylinder or pipeline. Integral flange. Because of the transition structure and butt welding connection of the taper neck, the strength and rigidity of the flange are strengthened, the butt welding flange is not easy to deform, well sealed and widely used.

      Sealing surface forms: RF, FM, m, t, G, FF......