METHOD AND DEVICE FOR INDUCTION HEATING WIRES

摘要

In the induction heating of thin (e.g. 0.5 to 3 mm diameter) steel wires (W) in continuous heating processes, relatively low field strengths of e.g. up to 20,000 Am-1 are employed but are chosen so as to set the relative magnetic permeability mu r at 40 or more. The wire are passed through coil blocks (1), which are wound flat around a row of ceramic tubes (3) to guide and insulate the wires. The coil blocks are energized at frequencies typically up to 30 kHz. The direction of winding and/or the phase of the current is changed between adjacent coil blocks (1), or groups of blocks, to reduce voltage build-up along the wires.