PURPOSE: To enable the surface quenching on a wide surface by suitably arranging plural pieces of plasma torches and adjusting the arc output of each torch.
CONSTITUTION: The plasma torches 1, 2 are fitted as mutually inclining and fitted and fixed to a shield cover 6 so that plasma arcs 3, 4 generated from the plasma torches 1, 2 concentrated in the narrow part. The plasma torches are set so that effective heating zone 10 of the plasma arcs 3, 4 becomes the range of interval (a) in the direction of the cross-sectional face A-A' and interval (b) in the direction of the cross-sectional face B-B'. The plasma arc heat source generates uniform heat input distribution having the effective heating zone 10 in A-A' direction. Plural plasma torch lines are shifted to B-B' direction and at the time of quickly heating the surface of material 5 to be treated, the wide quenched hardening part 9 is formed in A-A' direction and the furnace quenching on the wide surface can be executed. Further, by this method, the wide width surface reforming treatment of molten chilling treatment, solution heat treatment, alloying treatment, etc., is easily executed.
| JP2001110592 | ELECTRODE FOR PLASMA TORCH |
| JPH06320284 | PLASMA ARC POWER UNIT |
YAMADA TOSHIHIRO
IWAKURA AKITA
YONETANI EIJI
HITACHI CONSTRUCTION MACHINERY
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