Abstract: An improved deformable locking fastener system comprises a fastener, a deformable collar and a dedicated installation tool. The fastener has a threaded exterior defining a plurality of axial flutes which are configured to prevent the collar from prematurely capturing the fastener during installation. The collar comprises a cylindrical forward portion, a central portion having an elliptical cross-sectional shape and a rearward portion having an elliptical cross-sectional shape. The collar portions have axial heights selected to maximize the strength of the collar and to minimize the weight of the collar. The installation tool contacts the collar along driving ridges which reduces the radial compression of the collar and increases the tangential driving force turning the collar during installation.

Abstract: A torque measuring device is described that measures forces occurring during the interconnection of a nut to a bolt. The device has particular application with bolts having a key aperture in the tail end thereof and with nuts having a swaged exterior surface. A matching swage socket is used to limit the torque applied to the nut as material from the nut is swaged into fluted surfaces of the bolt. The torque measuring device is responsive to the torque applied to the nut, the reaction torque generated by the bolt and the compressive force between the nut and the bolt. The torques and the compressive force can be simultaneously measured and displayed so that an active force profile can be provided.

Abstract: An improved deformable locking fastener system comprises a fastener, a deformable collar and a dedicated installation tool. The fastener has a threaded exterior defining a plurality of axial flutes which are configured to prevent of the collar from prematurely captivating the fastener during installation. The collar comprises a cylindrical forward portion, a central portion having an elliptical cross-sectional shape and a rearward portion having an elliptical cross-sectional shape. The collar portions have axial heights selected to maximize the strength of the collar and to minimize the weight of the collar. The installation tool contacts the collar along driving ridges which reduces the radial compression of the collar and increases the tangential driving force turning the collar during installation.

Abstract: An installation tool for use with locking fasteners which reduces cam off during use. The tool comprises a cylindrical socket wrench having a central axial bore which defines a recess on one end for attachment to a socket driver and an elliptical cavity on the opposite end for engaging the collar of the locking fastener. The installation tool further comprises one or more pockets positioned on the wrenching portion of the cavity. The pockets provide space in which collar mass is deformed. As the collar is deformed to lock the collar and bolt together, collar mass is deformed into the pockets on the tool. The deformed collar mass retains the tool and collar in an engaged position until the collar is completely deformed and the fastener is locked.