Induction heating of metal objects - where inductor contains core cooled by liq. gas so heating power can be increased, esp. in mfg. seam welded pipe or tube

摘要

The process employs a heating inductor, plus a magnet core which is cooled by a cold liq. which is a gas at normal temps. The liq. is heated in cooling the core and evaporates to form a gas which is removed from the vicinity of the core. Alternatively, the liq. gas may be evaporated to form a cold gas which is then used to cool the core. The liq. is pref. N2, a noble gas, or CO2. The pref. appts. includes a protective sheath surrounding the magnet core to form an annular gap into which the cold fluid is fed so ice forms on the outside surface of the sheath. The process is pref. used for induction-welding, -brazing, and -soldering. Due to the efficient cooling of the core, the output of an induction welding plant employed in the mfr. of seam welded steel pipe or tube can be increased by 20%.