Intermediate Connection
Class 150 Nozzle Flanges
Intermediate connection flanges for Class 150 service
Class 150 Nozzle Flanges provide a convenient transition between vessel nozzle sizes and connected piping in low-pressure service. By combining the bolt pattern of the larger nozzle flange with the bore of the smaller pipe, these flanges eliminate the need for a concentric reducer and an additional flanged joint at each vessel connection.
The outer dimensions, bolt circle, and bolt hole pattern of a Class 150 nozzle flange match the corresponding B16.5 Class 150 flange for the larger (nozzle) size. The bore is machined to accept the smaller pipe, and the hub profile tapers from the larger outside diameter to the smaller bore, maintaining smooth internal flow transitions.
These flanges are commonly used on pressure vessels, heat exchangers, and storage tanks where instrument connections, drain nozzles, or small process taps require a flanged connection to the vessel shell. The Class 150 rating is suitable for atmospheric and low-pressure vessels in water treatment, HVAC, and general chemical processing.
