Orifice Union B16.36
Class 400 Weld Neck Orifice Flanges
B16.36 weld neck orifice flanges rated for Class 400 service
Class 400 Weld Neck Orifice Flanges bridge the gap between Class 300 and Class 600 pressure ratings, providing an intermediate option for systems that exceed Class 300 limits but do not require the full thickness and weight of Class 600 components. The B16.36 standard defines these flanges with the same pressure tap and orifice retention features as other classes.
Dimensional characteristics including outside diameter, bolt circle, and flange thickness follow the B16.5 Class 400 envelope, ensuring drop-in compatibility with standard Class 400 piping. The weld neck hub profile maintains a gradual taper that promotes smooth flow upstream and downstream of the orifice plate.
Class 400 orifice flanges are frequently specified in offshore oil and gas production platforms, high-pressure steam metering, and chemical processing facilities where operating pressures fall in the 600 to 1000 psi range at moderate temperatures.
