Angle Rings and Flanges
Angle Rings Construction Standards and Technical Data
Steel Angle Flanges are pressed or rolled and used widely in joining ductwork together in dust and fume control work. All angle rings are unpainted, mild steel (Galvanized, Stainless Steel and Aluminum available). Standard rings come punched with holes (un-punched available). Dimensions shown are typical. Nearly any bolt hole circle or hole size is available. Spiral Manufacturing Co., Inc offers a complete line of neoprene precut and punched gaskets or duct seal mastics. We also offer a full line of fabricated rectangular flanges punched or un-punched. For any other questions consult Factory.
Typical Angle Iron Ring Dimensions
Any size bolt hole, bolt circle, or material available.


The complete joint consists of two matching sets of face and backing flanges. If the duct wall selection for an industrial duct application is based on an “un-stiffened” design, the backing flanges may remain unattached with respect to the duct wall (standard). If the design requires a stiffening contribution from the flanged joint, flanges must be stitch welded to the duct wall per your specifications to ensure a dependable load sharing mechanism between the duct wall and the joint.