ASME B18.2.2 Hex Flange Nuts

ASME B18.2.2 Hex Flange Nuts are inch-series hexagonal nuts with an integral flange at the bearing end. The flange functions as a built-in bearing surface, increasing the contact area between the nut and the mating component compared with a conventional hex nut. This configuration is commonly referred to as a Hex Flange Nut or Flanged Hex Nut and is used with compatible inch-series bolts, screws, and studs.

ASME B18.2.2 establishes general and dimensional requirements for several types of inch-series nuts, including Hex Flange Nuts and Large Hex Flange Nuts. The current ASME B18.2.2-2022 edition specifically includes dimensional data for these nut types. The standard is therefore directly relevant to the dimensional definition of this product rather than being merely a related fastener reference.

The integral flange distributes the clamping load over a larger bearing area and can reduce the tendency of the nut to embed into the mating surface compared with a standard hex nut. Depending on the application, flange nuts may be used with flat or formed sheet-metal components, machine frames, brackets, equipment assemblies, and general mechanical structures. Serrated flange nuts are a related product variant, but they should not automatically be treated as identical to the standard non-serrated Hex Flange Nut covered by the general dimensional scope.

ASME B18.2.2 is an inch-series standard. Thread selection therefore needs to be specified separately according to the required inch thread system, such as UNC or UNF, rather than assuming that all B18.2.2 flange nuts use the same thread pitch. Material, mechanical grade, finish, and special locking features are also purchasing variables and should be confirmed according to the application and applicable material or performance requirements.