A fastener for assembling at least two structural elements having an aperture, may have a fastener comprising an enlarged head (12) and a shank (14) exhibiting, prior to fitting, an outside diameter (D.sub.1) greater than an inside diameter (D.sub.S) of the aperture, and a locking portion comprising a screw thread or annular grooves. The fastener further comprises a lubricating sacrificial ring (40) on the exterior surface of the fastener, extending at least between a distal end of the shank and a proximal end of the locking portion, said ring having, before the fastener is fitted into the structure, an outside diameter greater than a diameter of the aperture. The sacrificial ring comprises a polymer resin forming a matrix encapsulating dispersant molecules and oil molecules. The fastener assembly may apply to the assembly of aircraft structures.

A fastener for assembling at least two structural elements having an aperture, may have a fastener comprising an enlarged head (12) and a shank (14) exhibiting, prior to fitting, an outside diameter (D.sub.1) greater than an inside diameter (D.sub.S) of the aperture, and a locking portion comprising a screw thread or annular grooves. The fastener further comprises a lubricating sacrificial ring (40) on the exterior surface of the fastener, extending at least between a distal end of the shank and a proximal end of the locking portion, said ring having, before the fastener is fitted into the structure, an outside diameter greater than a diameter of the aperture. The sacrificial ring comprises a polymer resin forming a matrix encapsulating dispersant molecules and oil molecules. The fastener assembly may apply to the assembly of aircraft structures.

A device is disclosed for supplying swageable collars from a magazine to a swaging tool such that the collars may be affixed to the shanks of lockbolts in a series of application steps. The feeder device can be mounted on the nose assembly of a swaging tool so that collar feeding and swaging can be accomplished in a single-handed operation. The feeder device responds to contact pressure against a work surface during a collar placement maneuver to release a collar from a presentation position for normal swaging. Releasing pressure on the workpiece allows a lower assembly of the feeder device to lift the next collar available from a magazine into the presentation position for application to the next lockbolt shank in a series of lockbolts to be finished.

A device is disclosed for supplying swageable collars from a magazine to a swaging tool such that the collars may be affixed to the shanks of lockbolts in a series of application steps. The feeder device can be mounted on the nose assembly of a swaging tool so that collar feeding and swaging can be accomplished in a single-handed operation. The feeder device responds to contact pressure against a work surface during a collar placement maneuver to release a collar from a presentation position for normal swaging. Releasing pressure on the workpiece allows a lower assembly of the feeder device to lift the next collar available from a magazine into the presentation position for application to the next lockbolt shank in a series of lockbolts to be finished.

Systems and methods are provided for fastening via a swage tool. One embodiment is a method for fastening via a swage tool. The method includes steps of selecting a hole located at a part, aligning an axis of a lockbolt collar with a center of the hole, placing the lockbolt collar flush against the part at a first end of the hole, and swaging the lockbolt collar onto a lockbolt that has been driven through the hole. This securely fastens the lockbolt collar to the lockbolt.

Systems and methods are provided for inspecting installation of a fastener. One method includes monitoring hydraulic pressure of a tool that is installing the fastener, detecting that the hydraulic pressure has dropped by more than a threshold amount within a period of time, determining that a pintail of the fastener has snapped in response to the detecting, and reducing the hydraulic pressure in response to the determining.

Systems and methods are provided for inspecting installation of a fastener. One method includes monitoring hydraulic pressure of a tool that is installing the fastener, detecting that the hydraulic pressure has dropped by more than a threshold amount within a period of time, determining that a pintail of the fastener has snapped in response to the detecting, and reducing the hydraulic pressure in response to the determining.

A lockbolt collar having a shank including a first end, a second end opposite the first end, a through-bore extending from the first end to the second end, an inner wall extending from the first end to the second end, and a tab extending radially and outwardly from the inner wall, the tab including a top surface having an arcuate shape, the arcuate shape of the tab being sized and shaped to mate with at least one lock groove of a threaded portion of a pin member.

A lockbolt collar having a shank including a first end, a second end opposite the first end, a through-bore extending from the first end to the second end, an inner wall extending from the first end to the second end, and a tab extending radially and outwardly from the inner wall, the tab including a top surface having an arcuate shape, the arcuate shape of the tab being sized and shaped to mate with at least one lock groove of a threaded portion of a pin member.

The object of the invention is a cap to lubricate an inner wall of a perforation going through at least two elements of the structure. The cap comprises a tubular body and at least one lubricant reserve, and before installation in the structure said cap has a largest external diameter larger than an internal diameter (D.sub.S) of the perforation, and the cap lubricates the internal surface of the perforation when its largest external diameter is radially compressed by a wall of the perforation. The invention also concerns a fastener comprising this type of cap, and an interference assembly process for the fastener equipped with the cap. The invention is applicable to the assembly of aircraft structures.