What are blind flanges?

A blind flange is a round plate with all the necessary blowholes except for the centre hole. Because of this characteristic, blind flanges are typically used to seal the ends of piping systems and pressure vessel openings. They also allow easy access to the inside of a pipe or vessel after it has been closed and needs to be reopened.

Without the blind flange, maintenance and repair of a pipeline would be difficult. The flow would have to be stopped at the nearest valve, which could be miles away from the repair site. In addition, valves are expensive and prone to sticking. A pipe can be sealed with a blind flange at a much lower cost. Blind flanges are commonly used in the petrochemical, pipeline, utility and water treatment industries, among others.

A Blind Flange (BF) is a piping component used to cover or seal the end of a pipe, valve, vessel or tank. When used at the end of a pipe, vessel or tank, it provides easy open access for further extension of the pipe. The blind flange is subjected to greater stress than any other flange because its primary function is to limit the pressure of the pipe.

Blind flanges – abbreviated BV – are widely used in all industries where pipes are used. They are available in all face types (RTJ, Raised and Flat Face) and pressure ranges. Although it’s not a good idea in most pipework, a blind can be placed between two flanges to impede flow. The designer should use a blind when attempting to temporarily obstruct flow in a pipe. A blind flange is placed at the end of a valve to prevent process fluid from escaping if the valve is accidentally opened.