Walking beam type reheating furnace

Claim 1

A walking beam type reheating furnace which comprises: a furnace housing having a charge opening defined at one end thereof for charging a workpiece therethrough and a discharge opening defined at the other end thereof for discharging said workpiece therefrom, with an exhaust port for exhausting gas inside said housing being formed on the charge end of the furnace and a door being arranged on each of said openings; a plurality of stationary beams extending in a longitudinal direction of the furnace; a plurality of movable beams parallel to said stationary beams and extending in said longitudinal direction of the furnace, said movable beams being separated at least into first movable beams on the charge side of the furnace and second movable beams on the discharge side thereof, each of which movable beams is provided with a vertical and a horizontal drive unit; workpiece transfer means for removing an individual workpiece from any position on said stationary beams and said first movable beams in the charge end of the furnace and moving the individual workpiece to a position in the vicinity of a separating portion of the furnace at which the first and the second movable beams are separated from each other in the longitudinal direction, said transfer means being movable vertically a distance sufficient to lift the individual workpiece above any other workpieces on the first movable beams and stationary beams in the charge end of the furnace and being movable longitudinally to move the individual workpiece over any other workpieces located in the charge end of the furnace during transfer of the individual workpiece to the separating portion of the furnace; and an intermediate door movable in a vertical direction and arranged on a top wall of the furnace at the separating portion of the first and the second movable beams, with an exhaust port being defined in a portion of the furnace containing the second movable beams and in the vicinity of said intermediate door; wherein a workpiece can be transferred to said separating portion, while being supported on said workpiece transfer means in a zone where said first movable beams are located.