EN1092-1 Type 11 WN Flange

EN1092-1 type11 welding neck flange are distinguished from other types by their long tapered hub and gentle transition of thickness in the region of the butt weld joining them to the pipe. The long tapered hub provides an important reinforcement of the flange proper from the standpoint of strength and resistance to dishing. The welding neck flanges are normally refered to as the high hub flange. It is designed to transfer stress to the pipe, thereby reducing high stress concentrations at the base of the flange. The welding neck flange is the best designed butt welded flange of those currently avaliable because of its inherent structural valve. It is expensive because of the design.