US Patent 11841041 Fastening collars, multi-piece fastening systems, and methods of fastening

Fastening collars, multi-piece fastening systems, and methods of fastening are provided. The fastening collar comprises a first end, a second end, and an elongate portion intermediate the first end and the second end and defining a longitudinal axis of the fastening collar. The elongate portion comprises a first region adjacent the first end, a second region intermediate the first region and the second end, and a cavity. The first region comprises a first diameter and is configured to be received by a bore of a structure. The second region comprises a second diameter greater than the first diameter. The cavity extends through the elongate portion and is configured to receive at least a portion of a shank of the multi-piece fastening system. The elongate portion is configured to at least partially deform onto the shank responsive to forcible contact between the second region and an installation tool.