The method of fabricating low-cast, high-yield strength weld wire for welding includes displacing the weld wire through a rotary straightener having a pair of dies rotatable in opposite directions. Each die has a slider for introducing a bend in the wire as the wire is fed through entry and exit openings of the die. By rotating the dies in opposite rotational directions with bends introduced in the wire in the dies, the wire is cold work-hardened. The wire exiting the dies is wound on a spool. The weld wire when unwound from the spool has a low-cast and a high-yield strength.

An apparatus for manufacturing a cable bolt from a cable (1) includes first and second clamps (2, 3) adapted to releasably clamp the cable (1) with the cable (1) extending along the longitudinal axis (4) of the apparatus. A first cable displacement device (12) longitudinally displaces the first clamp (2) relative to the second clamp (3) along the longitudinal axis (4). A first clamp rotation device (14) rotates the first clamp (2) relative to the second clamp (3) about the longitudinal axis (4). The apparatus also has a second clamp displacement device (19) for simultaneously longitudinally displacing the first and second clamps (2, 3) along the longitudinal axis (4).

Bulges in a wire having helically coiled strands are formed by untwisting the strands in an anti-helical direction at a predetermined position, to form an electrical connector from a length of the stranded wire. The wire is gripped by moving two spaced apart clamp members to a closed position and thereafter rotating the clamp members relative to one another in at least one complete relative revolution in a direction which is anti-helical relative to the coiled strands to form the bulge. The wire is gripped and rotated in the anti-helical direction for a relative rotational interval of greater than one-half, and preferably three-fourths, of a complete relative revolution. Thereafter, during the remaining rotational interval of each relative revolution, the clamp members are opened to permit the wire to be advanced to the next position where a bulge is to be formed.

Bulges in a wire having helically coiled strands are formed by untwisting the strands in an anti-helical direction at a predetermined position, to form an electrical connector from a length of the stranded wire. The wire is gripped by moving two spaced apart clamp members to a closed position and thereafter rotating the clamp members relative to one another in at least one complete relative revolution in a direction which is anti-helical relative to the coiled strands to form the bulge. The wire is gripped and rotated in the anti-helical direction for a relative rotational interval of greater than one-half, and preferably three-fourths, of a complete relative revolution. Thereafter, during the remaining rotational interval of each relative revolution, the clamp members are opened to permit the wire to be advanced to the next position where a bulge is to be formed.

Twist pins having bulges are fabricated from helically coiled stranded wire. Wire is advanced from a source such as a spool to create slack wire configuration, and wire is then advanced from the slack wire configuration to a position where each bulge is formed. Each bulge is formed by gripping the wire in two spaced apart locations and rotating the wire in an anti-helical direction in a single continuous relative revolution to untwist the strands and form the bulge. The wire is thereafter advanced to the position of the next bulge or the position where the wire will be severed to release the fabricated twist pin. The severed fabricated twist pin is conveyed through a flow of gas in a delivery tube into a receptacle of a cassette where the twist pin is stored until used. The cassette is automatically moved to position an occupied receptacle to receive each newly fabricated twist pin.