Abstract: A carburization and quenching apparatus includes: a plurality of carburizing chambers for carburizing thin plate parts; a gas cooling chamber for cooling the thin plate parts carburized in the carburizing chambers; and a reservoir tank 3 connected to the gas cooling chamber for delivering a cooling gas into the gas cooling chamber. The plurality of carburizing chambers are positioned at an approximately equal distance from the gas cooling chamber to surround the gas cooling chamber.In a continuous furnace, thin plate parts can be transported successively at least between a carburizing chamber and a pressurized cooling chamber. The thin plate parts are carburized in the carburizing chamber and then rapidly quenched in the pressurized cooling chamber by cooling the thin plate parts with a pressurized gas which can be e.g. inert gas.

Abstract: A process for hardening a plurality of holed flat parts. The holed flat parts are heated by inserting a cantilever hanger into the holes of the holed flat parts to support them in vertical positions within a furnace. The holed flat parts are then removed from the hanger by inserting a moving fork into the holes of the holed flat parts and moved to a cooling section while being supported in the vertical positions on the moving fork. Then, the holed flat parts in the vertical positions are quenched in the cooling section by blowing a gas downward to them. Also disclosed is an apparatus for practicing the holed flat part hardening process.