Patent ID: 7438773

Claim:
A method of manufacturing a blind threaded insert from metal comprising a first zone and a second zone, the second zone including a nut portion, and the first zone including a radially enlarged head at one end remote from the second zone, a single deformable section, a first transition section between the deformable section and the head, and a second transition section between the deformable section and the second zone, the deformable section having a higher relative ductility than the remainder of the insert; and extending over a greater length of the first zone than the length over which each of the transition sections extend; which method comprises the steps of: (a) at least partially forming the insert, by a cold-forming process, other than an internal thread; (b) forming the internal thread in the nut portion; and (c) annealing the first zone of the insert to produce a ductility in the deformable section which is higher than the ductility of the remainder of the insert and so that the deformable section has a hardness value which is lower than the hardness of the nut portion and which is of a substantially constant value along its length in order to promote later deformation in the deformable section during installation of the insert.