Blind pipe flanges

Blind pipe flanges are pipe flanges used to seal the end of a piping system or pressure vessel openings to prevent flow.
Blind pipe flanges are commonly used for pressure testing the flow of liquid or gas through a pipe or vessel. Blind pipe flanges also allow easy access to the pipe in the event that work must be done inside the line. Slip on Pipe flanges with a hub have published specifications that range from 1/2″ thru 96″. Coastal Flange provides Blind pipe flanges in all material grades, specifications and sizes.
Blind pipe flanges are typically provided with a raised face, flat face, or RTJ facing. When a raised face is necessary for blind pipe flanges, the standard height is 1/16″ for blind pipe flanges under 400#. For blind pipe flanges of 400# and up, the standard blind pipe flange raised face height is 1/4″.
Features of blind flanges:

Some important features of blind flanges are as follows:

Blind flanges are sometimes supplied with NPT fittings which allow pressure test connections to be fitted.
They are used to blank off the ends of pipe.
They are also used to blank off the ends of valves and pressure vessel opening.
Considering factors like internal pressure and bolt loading, blind flanges, especially in the larger sizes, are the most highly stressed of all types of flanges.
Since the maximum stresses in a Blind Flange are bending stresses at the center, they can safely be allowed to be higher than in other types of flanges.
Blind flanges are made to fit standard pipes in all sizes.