CONTINUOUS HEAT TREATMENT FURNACE HAVING JET PREHEATING ZONE

摘要

PURPOSE:To always maintain optimum infurnace pressuer with respect to delicate changes in furnace pressure by making the jet nozzles of arbitrary rows in a jet preheating zone variable of their ejection direction in the furnace length direction. CONSTITUTION:Jet preheaters A, B are provided to a preheating zone 3 of a furnace. The device A has a baffle 8 provided with plural raws of jet nozzles 9 extending in the furnace width direction and having long-sized openings directing to the charging port 6 side on the under surface thereof. With the device B, at least part of the nozzles 9A are made oscillatable in the furnace length direction. Namely, when an operating shaft 20 is rotated by a handle 22 on the outside of the furnace, the nozzles 9A are oscillated laterally, that is, in the furnace length direction by way of a key 21. The other nozzles 9a are coupled integrally oscillatably by a linkage 24 pivotally supported freely turnably by means of a pin 23. The change in the furnace pressure of the heating and soaking zone 1 is adjusted by suitably oscillating these nozzles 9A, and the optimum infurnace pressure is thus maintained.