A reduced ring groove rivet at least includes a pin having a head and a body connected to the head; a plurality of sets of ring grooves are equidistantly arranged on the body, and each of the sets of ring grooves includes a first ring groove and a second ring groove adjacent to the first ring groove, wherein the first ring groove has a first groove bottom and a first groove peak adjacent to the first groove bottom, and the second ring groove has a second groove bottom and a second groove peak adjacent to the second groove bottom; a diameter of the second groove bottom is smaller than a diameter of the first groove bottom, or a diameter of the second groove peak is smaller than that of the first groove peak, so that any of the plurality of sets of ring grooves can be breaking part during operation.

A reduced ring groove rivet at least includes a pin having a head and a body connected to the head; a plurality of sets of ring grooves are equidistantly arranged on the body, and each of the sets of ring grooves includes a first ring groove and a second ring groove adjacent to the first ring groove, wherein the first ring groove has a first groove bottom and a first groove peak adjacent to the first groove bottom, and the second ring groove has a second groove bottom and a second groove peak adjacent to the second groove bottom; a diameter of the second groove bottom is smaller than a diameter of the first groove bottom, or a diameter of the second groove peak is smaller than that of the first groove peak, so that any of the plurality of sets of ring grooves can be breaking part during operation.

Multi-piece fasteners, fastening collar installation apparatus, and methods of fastening are provided. The multi-piece fastener comprises a fastening collar and a pin. The fastening collar comprises a first collar end, a second collar end, and a collar cavity. The collar cavity extends from the first collar end to the second collar end. The pin is configured to be at least partially received by the collar cavity. The pin comprises a first pin end comprising a head portion, a second pin end comprising a pull region, and a shank. The pull region is generally cylindrical and smooth and is configured to form at least one of an annular shoulder, a groove, a thread, and other feature responsive to forcible contact from a fastening collar installation apparatus. The shank extends intermediate the first pin end and the second pin end. The fastening collar is configured to be deformed onto the shank.

Multi-piece fasteners, fastening collar installation apparatus, and methods of fastening are provided. The multi-piece fastener comprises a fastening collar and a pin. The fastening collar comprises a first collar end, a second collar end, and a collar cavity. The collar cavity extends from the first collar end to the second collar end. The pin is configured to be at least partially received by the collar cavity. The pin comprises a first pin end comprising a head portion, a second pin end comprising a pull region, and a shank. The pull region is generally cylindrical and smooth and is configured to form at least one of an annular shoulder, a groove, a thread, and other feature responsive to forcible contact from a fastening collar installation apparatus. The shank extends intermediate the first pin end and the second pin end. The fastening collar is configured to be deformed onto the shank.

A fastening assembly includes: a panel defining an aperture; a fastener having a cap and a shaft extending from the cap, the shaft being disposed through the aperture, the fastener having a first corrosion rate, and the fastener including: a recess formed in the cap and extending at least partially around the shaft; face surfaces that are planar and that are to directly contact the panel; and recessed channels that are disposed between the face surfaces, respectively, that are recessed relative to the face surfaces, and that extend from a radially outer edge of the cap to the recess; and an anode insert disposed in the recess and having a second corrosion rate that is faster than the first corrosion rate.

A method for installing a fastener system. A position on a structure relative to an overhang on the structure is automatically sensed for installing a fastener system in a hole using an offset collar installer. The offset collar installer is moved about a rotation axis to the position such that a collar in the fastener system is held in the position over the hole. The offset collar installer is connected to a platform and rotatable about the rotation axis. The collar is fastened to an engagement feature for a bolt in the hole.

A method for installing a fastener system. A position on a structure relative to an overhang on the structure is automatically sensed for installing a fastener system in a hole using an offset collar installer. The offset collar installer is moved about a rotation axis to the position such that a collar in the fastener system is held in the position over the hole. The offset collar installer is connected to a platform and rotatable about the rotation axis. The collar is fastened to an engagement feature for a bolt in the hole.

A fastener including a pin member having a shank portion, a threaded portion having a thread, a lock portion having at least one lock groove, and a pull portion located having at least one pull groove. The threaded portion is adapted to be engaged threadedly with a threaded hole of a workpiece to install the pin member therein. The fastener includes a swage collar adapted to be installed into the at least one lock groove of the lock portion to secure a plurality of workpieces. The pull portion is adapted to break off when the fastener is installed.

A fastener including a pin member having a shank portion, a threaded portion having a thread, a lock portion having at least one lock groove, and a pull portion located having at least one pull groove. The threaded portion is adapted to be engaged threadedly with a threaded hole of a workpiece to install the pin member therein. The fastener includes a swage collar adapted to be installed into the at least one lock groove of the lock portion to secure a plurality of workpieces. The pull portion is adapted to break off when the fastener is installed.

A fastener including a pin member having a shank portion, a threaded portion having a thread, a lock portion having at least one lock groove, and a pull portion located having at least one pull groove. The threaded portion is adapted to be engaged threadedly with a threaded hole of a workpiece to install the pin member therein. The fastener includes a swage collar adapted to be installed into the at least one lock groove of the lock portion to secure a plurality of workpieces. The pull portion is adapted to break off when the fastener is installed.