METHOD OF FASTENING

摘要

A method and fastener for fastening one or more apertured members 48 to an apertured workpiece 52, an aperture 50 of the or each member 48 being aligned with an aperture 54 in the workpiece 52, the method comprising the steps of inserting a fastener 10 into the aligned apertures, the fastener 10 being formed of ductile material and having a head 14, a shank 12, and an axial bore 22 extending through the shank 12 and into the head 14, the shank 14 being circumferentially entire and being formed with an external screw-thread 18 the fastener 10 being inserted so that the head 14 engages a face of the one member 48, and the shank 12 extends through the member 48 or members and into the workpiece 52, and at least a part of the screw-thread 18 is within the workpiece 52, and then, while supporting the fastener 10 at the head 14, drawing into and entirely through the bore 22, in the direction from the tail portion to the head 14, a tapering, enlarged, mandrel head 32 capable of expanding the bore 22 and thereby enlarging the bore 22 evenly throughout its length and causing ductile radial expansion of the shank 12 sufficient to case the external screw-thread 18 to embed in the workpiece 52 and the shank 12 of the fastener 10 undergoing ductile axial reduction in length.