Rethreading die and method

Abstract

The invention comprises an improved rethreading die, a method of making the die, and a method of rethreading an in situ stud member. The workpiece from which the die is formed has oppositely directed front and rear faces and laterally outwardly facing side surfaces about the periphery of the front and rear faces. Recesses are formed in said workpiece for receipt of a hinge and its retaining pins. The hinge and pins are fitted in the recesses in the workpiece. The hinge and pins are removed, and the workpiece is divided, generally transversely with respect to the front and rear faces, into a pair of die members. The hinge and pins are then replaced in their recesses in engagement with positioning reference surfaces formed by those recesses. The die members thus formed and hingedly connected each have a first end, the first ends being disposed generally adjacent each other to one side of an inner opening formed prior to splitting of the workpiece. The second ends of the two die members are disposed generally adjacent each other and spaced about the inner opening from the first ends. The hinge mechanism permits the second ends of the two die members to be moved toward and away from each other between an open position permitting passage of a stud between the second ends into the inner opening and a closed position permitting engagement of thread forming surfaces adjacent the opening with the stud. Thus, the die may be emplaced about an undamaged inboard portion of an in situ stud, external wrench surfaces on the die can be engaged with a retaining tool, and the die rotated with that tool in a direction to move it progressively outwardly along the stud and over damaged outboard threads.

Dependencies are inferred from the claim text.