Process for the temporary shutdown of continuous discharge carburizing plants

Abstract

A process for the temporary shutdown of continuous-discharge carburizing plants wherein a plurality of metallic components to be hardened are conveyed on a conveyor means in succession through a heating-up zone; a carburizing zone; a pearlitizing zone, if present; and a hardening zone, each zone having an operating gas atmosphere, involves the following steps: (a) clearing the hardening zone of carburized metallic component products; (b) stopping the conveyor means, lowering the temperature in the heating-up, carburizing, and hardening zones to 600.degree.-800.degree. C., and replacing the operating gas atmosphere in each zone by an inert gas atmosphere for the temporary period of shutdown; (c) bringing, after termination of the shutdown period, the heating-up, carburizing, and hardening zones to a predetermined temperature of 850.degree.-880.degree. C., and when a zone has reached the predetermined temperature, replacing the inert gas atmosphere with the operating gas atmosphere; and (d) when all zones have reached the predetermined temperature according to step (c), bringing the hardening zone and the carburizing zone to a rated operating temperature, and thereafter activating the conveyor means, then bringing the heating-up zone to a rated operating temperature.

Dependencies are inferred from the claim text.