Abstract: The method of rivet installation creates a preload on the workpieces being joined. The installation steps include inserting a rivet into two or more workpieces to be joined and engaging the head of the rivet with an upper two piece tooling assembly while engaging the tail of the rivet with a counterbore provided in a lower tool. In phase one of installation, which follows these engagement steps, the lower tool exerts a compressive force upon the rivet tail, thereby deforming the tail to form a lower upset head. In phase two of installation, an inner retractable pin of the two piece tooling assembly is withdrawn from contact with the rivet head while an outer ring tool of the tooling assembly exerts a compressive force upon peripheral portions of the rivet head, thereby deforming the rivet head periphery to form an enlarged rim comprising an upper upset head. This deformation of the rivet head periphery produces a preload. Both phase one and phase two of installation are executed in one continuous motion.

Abstract: A rivet installation method creates a preload on the workpieces being joined. The rivet shank is urged to resist compression during installation while a ring on the end of the shank is compressed against the workpieces. Withdrawing the compression releases the shank to provide the preload.

Abstract: A rivet installation method creates a preload on the workpieces being joined. The rivet shank is urged to resist compression during installation while a ring on the end of the shank is compressed against the workpieces. Withdrawing the compression releases the shank to provide the preload.

Abstract: A fastening nut, which by virtue of precisely located laser cuts and the application of predetermined torque to a grip member, is enabled to break into several parts, one of which can be used as a jam nut. The nut is provided with an internally threaded sleeve, a grip member and interconnecting means, the latter of which may be provided with one or more shear areas by virtue of a series of laser cuts. At a predetermined torque on the grip member, the sleeve is sheared from the interconnecting means and grip member and, as a second embodiment, the interconnecting means may be provided with internal fastening threads so that further torquing of the grip member drives such interconnecting means into the sleeve and thereafter a second shear separation is effected to remove the grip member from the jam nut.

Abstract: A blind fastener capable of providing a strong fastening force on workpieces whose composite thickness may vary from minimum to maximum within a predetermined range. It comprises a tubular sleeve and pulling mandril therewithin, such mandril having a head which is pulled against the blind end of the sleeve to cause the same to be crimped or upset against the blind side of the workpieces. The sleeve is formed with a tapered end portion which varies from maximum wall thickness at the blind end thereof to minimum thickness intermediate the length of the sleeve. The mandril is formed with a complementally-shaped taper which varies from the head of the mandril to a point intermediate the length thereof.

Abstract: A blind rivet stem extending through a hollow rivet so that it may be pulled, thereby to expand the tail of the hollow rivet; a collar on the stem has a head fitting in a locking groove within the grip length of the stem so that when the tail of the collar abuts a pressure element bearing against the head of the hollow rivet, it is bulged outwardly into a recess in the rivet head, thereby to interlock the rivet stem and the hollow rivet; a weakened portion such as a break groove is provided on the stem adjacent the bulged end of the collar whereby upon further pulling the rivet breaks at said weakened portion.

Abstract: A blind fastener wherein a push-pull type setting tool is employed for pulling a stem into a predetermined position relative to a sleeve, and a two element shear washer is provided to fail at a predetermined shear load as created by the compressive load on the sleeve and the reaction tensile pull on the stem. Failure of the shear washer drives a locking collar between the stem and sleeve.The shear washer comprises a pair of concentric but axially offset elements joined together by an annular shear web which, upon shear failure allows one of the elements to drive an annular locking collar between the stem and sleeve. Such shear washer together with the rivet sleeve are serially placed under compression to counteract the tensile force applied to the stem.