Blind Flange BL ASTM A182 ASME / ANSI B16.5

Blind Flange

A Blind Flange BL manufactured in accordance with ASTM A182 specifications is a specific type of flange used in piping systems for various industrial applications.

A Blind Flange BL is a solid disk with no bore (hole) in the center. It is used to close the end of a piping system or a pressure vessel opening. The BL designation indicates that it is a Blind Flange.

ASTM A182 is a standard specification for forged or rolled alloy and stainless steel pipe flanges, forged fittings, and valves for high-temperature services. A Blind Flange BL made from ASTM A182 material is designed to withstand high pressures and temperatures.

The Blind Flange BL is a solid disk with no openings, providing a closure for the end of a pipeline.

Blind flanges manufactured in accordance with ASME B16.5 can be provided in Class 150 through Class 2500. It is basically a circular disc that does not have a hub or bored center. Bolts holes are drilled and aligned symmetrically along the circumferential edge of the solid disc. Generally the blind flange may be furnished with raised face (RF), ring join face (RJ), or flat face (FF). The blind flange serves a function similar to that of a plug or cap and is used to blank off the end of piping, valves and pressure vessel openings. It may be fabricated from cast, forgings, specific plates, or flat bars.

Product Information

Advantages & Disadvantages: Applications

Since it is bolted, the blind flange provides easy access to the interior of a vessel or pipe, unlike a cap that is welded. From the standpoint of internal pressure and bolt loading, blind flanges, particularly in large sizes, are the most high-stressed of all the standard flange types. However, since the maximum stresses in the blind flange are bending stresses at the flange center (that is robust enough to withstand the stresses), they can be safely permitted to be stressed more than other types of flanges.