| 摘要 |
<P>PROBLEM TO BE SOLVED: To carry out a surface treatment uniformly in the width direction even when cast billets and steel billets have a variety of widths. <P>SOLUTION: In an apparatus having a plurality of plasma torches T1 to T7 arranged in parallel with each other so as to generate plasma arcs P between the cast billets H and the plasma torches, electromagnetic coils 22, 24 are arranged outside the respective plasma torches T1, T7 located at both ends so as to generate an AC magnetic field in the direction opposed to the direction of the AC magnetic field generated by an electromagnetic coil 12 in order to reciprocate the plasma arc P in the width direction A. The electromagnetic coils 22, 24 can move toward the central side along the parallel direction of the plasma torches T1 to T7. The outward amplitudes only of the plasma arcs P can be controlled by the AC magnetic fields of the electromagnetic coils 22, 24. <P>COPYRIGHT: (C)2008,JPO&INPIT |
