| 摘要 |
<p>The steel wire, used for re-inforcing concrete, is made in a rolling mill from a billet. The resulting coil of wire is too short for some purposes, so a device is used to join the ends of two coils. The ends of each coil, the so-called 'hooks', are first cut-off by power shears and then clamped into grooves in the welding head. The clamping electrodes move together, bringing the cut ends into contact with each other, and a weld is made using the 'current-shock' or the burn-off' arc method. The welding produces a thickening of burred metal which is removed by cutting edges on the electrodes, as the hot joint is drawn through the head after welding.</p> |
