F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
F27D11/00—Arrangement of elements for electric heating in or on furnaces
F27D11/02—Ohmic resistance heating
F27D11/04—Ohmic resistance heating with direct passage of current through the material being heated
H—ELECTRICITY
H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
H05B3/00—Ohmic-resistance heating
H05B3/60—Heating arrangements wherein the heating current flows through granular powdered or fluid material, e.g. for salt-bath furnace, electrolytic heating