This is the AWWA B16.5 Class 300# Weld Neck Flange with an outside diameter based on the nominal pipe size (NPS) of 2 1/2". The inside diameter is based on the Nominal Pipe Size Chart of 80S.
This chart will give you the wall thickness, which in turn will give you the internal diameter. These Weld Neck Flange flanges are available in both a raised or flat face. The gasket typically requires a spiral or concentric surface, but we can offer additional finishes such as cold-water finish and Blanchard ground.
Order yours today to experience the best in flange customization.