GB384285A - Process of operating arrangements for annealing and subsequent cooling of rolled metal - Google Patents

Abstract

384,285. Metal - heating furnaces. DODERER, W. H., Neudek, near Karlsbad, Czecho-Slovakia. Feb. 23, 1931, No. 5645. Convention date, March 15, 1930. Void [Published under Sect. 91 of the Acts]. [Class 51 (ii).] Gases, supplying.-Relates to furnaces for heating metal in an atmosphere of protective gas, and comprises modifications in the method of starting-up the furnace, in the heating arrangements, in the means for throttling the flow of protective gas, and in the conveyer arrangements. The furnace shown in Figs. 1, 1a, and 1b comprises a feed channel 1 with a roller conveyer R<1>, and flaps 1a, which yield to the passage of the charge G ; a muffled heating section with step-by-step conveyer elements T<1> . . T5, and a fixed roller-way R<5>; and a cooling section separated from the heating section by a water-cooled slide 7 and an adjustable flap 5 for controlling the pressure within the muffle. The cooling section is enclosed by hollow cooled walls with light explosion covers. E and is fitted with flaps K consisting of sheet metal plates, stiffened by turning up their lower edges, which are adapted to contact and make a seal with strips of felt soaked in oil &c. In starting the furnace the slide 7 is closed,. and the muffle is scavenged by protective gas, and the cooling section first by steam, and finally by protective gas. When the muffle is incandescent the slide 7 is opened, and the charge is passed through for treatment. Charges, conveying.-The step-by-step conveyer elements T<1> &c. each consists of a double charge support 16, Fig. 2, actuated through frames 15a from eccentrics 17, the driving mechanism being located some distance below the muffle and protected from the heat by covered water coils 25. The charge supports can be disconnected from the driving mechanism and lowered on to a support S for inspection and repair. The shaft carrying the eccentrics 17 is hollow and has within it a water-cooling pipe surrounded by a copper sleeve. The conveying members are driven, and the inclination of the furnace is arranged, so that the speed of the charge increases as it travels through the muffle. The charge may be carried through the furnace on trays P, Fig. 6, stiffened at one end by a tube R inserted in a pocket p<1>, and when a step-by-step conveyer is used in the cooling-zone the charge may be deposited between the feeding strokes on water- or steamcooled boxes. The furnace may be fired by burners 36, Fig. 15, delivering into transverse recesses 35 in the arched roof, the muffle cover 30 being protected from the direct action of the flame by a bridge 41. The transverse cross section of the heating space increases in the direction of flow of the gases, which is counter-current to the movement of the charge. The furnace may be internally heated, and in this case the outlet flue is beneath the floor of the heating chamber. When used for annealing metal strip or wire the furnace may be situated between two rolling mills, and the ends may be made gastight by feeding the metal between asbestos packing or pairs of rollers.