blindflenzen

Blindflenzen, commonly referred to as blind flanges, are solid, disk-shaped closures used to seal the ends of piping systems or pressure vessels. They provide a leak-tight seal and offer a future access point for maintenance, inspection, or expansion.

Blind flanges have bolt holes around a central face and no bore, allowing them to match standard flange bolt patterns. They are made from various materials, including carbon steel, stainless steel, and alloys, and can feature flat-face or raised-face designs, which influence gasket selection.

Sizes and pressure ratings follow standard flange specifications. Typical sizes range from nominal pipe size 1/2 inch to 48 inches, and ratings span ASME B16.5 classes from 150 to 2500, depending on material and service.

Standards and compatibility: Blind flanges conform to ASME B16.5 for standard flanges, with large-diameter variants addressed by ASME B16.47. The drilling pattern must align with the mating flange.

Installation and use: A gasket is used between mating surfaces when the blind flange is installed as part of a larger assembly. Bolts are tightened in a cross-pattern to the specified torque, and re-torquing may be required after thermal cycles or maintenance.

Applications: Blind flanges are used to close pipe ends for testing, maintenance, or future equipment installation in industries such as oil and gas, chemical processing, power, and water treatment.

German usage: Blindflansch is the term in German; plural Blindflansche. The form blindflenzen is a less common variant.