摘要 |
<p>A scanning induction hardening process, in which a steel workpiece (5) is surface hardened by progressively traversing its length with an inductor coil (14), energised by an alternating electric current and immediately thereafter quenching the heated portion of the workpiece (5), characterised in that straightening of bends in the workpiece (5) being surface hardened is controlled during the induction hardening process by monitoring the straightness of the workpiece (5) and utilising information thereby obtained to control the heating and quenching of the workpiece (5), in such a manner, that a layer of hardened material of greater thickness is formed on the concave side of any bend in the workpiece, such as to produce a straightening moment acting to remove the bend. Apparatus for carrying out the above process is also disclosed and consists of an induction coil (14) with cooling passages (15) connected to flexible pipes (16), all mounted on bus bars (17). Immediately beneath induction coil (14) is quench ring (19), incorporating toroidal passage (20), extending into a plurality of holes (21), from which issues the quench fluid fed from flexible pipe (21a) on to workpiece (5). This part of the apparatus is in turn integrated with automatic monitoring and control apparatus for maintaining the straightness of the workpiece, as described above.</p> |