US 4,111,644 AGranted

Rotary hearth furnace with preheat conveyor

AssigneeSelas Corporation of America

InventorRobert E. Buckholdt

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Abstract

Rotary furnace and preheater structure, wherein a billet is heated on an enclosed preheat conveyor where waste gases from the rotary hearth furnace preheat the billet counter to the billet travel direction. The preheated billet is inserted into the rotary hearth furnace wherein combustion gases, exiting from burners mounted in the furnace roof or sidewalls, flow counter to the hearth rotation direction and exit into the enclosed preheat conveyor. A baffle, depending from the stationary furnace roof, controls combustion gas movement counter to the billet travel direction in the furnace, and forces the combustion gases out of the furnace through a flue communicating with the preheat conveyor. A source of aspiration is provided to communicate with the preheat conveyor, and thus to facilitate combustion gas movement therethrough.

Claims11

Dependent claims

A rotary hearth furnace for heating work pieces comprising:

(a) means forming a rotatable hearth having a roof thereon;
(b) combustion means within said furnace and emitting hot gases therein;
(c) a substantially enclosed preheat conveyor disposed about the outside periphery of said hearth and provided with means to move said work pieces about said periphery;
(d) passage means providing gas communication from said furnace to said preheat conveyor;
(e) means forming a loading and unloading station for the preheat conveyor and for the furnace;
and
(f) flow diverting means within said furnace for diverting the flow of combustion gases from said heating means through said passage means (d) and into said preheat conveyor, said passage means being located to provide a combustion gas current that is counter to the hearth travel direction and also counter to the travel direction of said work pieces on said preheat conveyor.

4 more elements

Dependencies are inferred from the claim text.