Welding Neck Flanges (RFWN Flange) are easy to recognize. They include a long tapered hub that gradually meets the wall thickness from the pipe or fitting.
The long tapered hub provides an important reinforcement for use in several applications involving high pressure, sub-zero and / or elevated temperatures. In conditions of repeated bending, caused by line expansion or other variable forces, the smooth transition from flange thickness to pipe or fitting wall thickness is extremely beneficial.
This flange type will be welded to a pipe or fitting with a single full penetration, V weld (Buttweld).
A105 - The standard forged carbon steel piping components for ambient and high temperature / pressure systems
SS304 - A common standard for stainless steel due to its malleability, high corrosive resistance weld-ability
SS316 - A molybdenum stainless steel that provides excellent tensile, creep and stress-rupture strengths at elevated temperatures