GB839004A - Electric heating apparatus for fluids - Google Patents

Abstract

839,004. Electric fluid heaters. HYNES, L. P. Aug. 3, 1956 [Aug. 12, 1955], No. 24055/56. Class 39(3) Electric heating apparatus for fluids comprises at least one heater tube containing an electric heater element, a flow tube surrounding the or each individual heater tube and spaced therefrom, partition walls extending out from the heater tube at circumferentially spaced positions and engaging the flow tube and dividing the space between the heater tube and the flow tube into a plurality of longitudinal heating passages, means closing one end of the flow tube and a cross connection between adjacent passages at said end of the flow tube. As shown, Figs. 3 and 4, a heater tube 30 having a closed end 31 and containing heating elements (not illustrated) extending through openings in insulators (Fig. 1a, not shown) and having radially opposite longitudinal partitions 35 is enclosed in a rectangular flow tube 36 so that the outer ends of the partitions 35 are located in the corners 38, a space 41 being left at the rear of the tube 36 to provide a cross connection between two heating passages 42 and 43 on opposite sides of the partitions 35. The flow tube is notched on two adjoining sides (Fig. 5, not shown), allowing the direction of flow to be established when flow tubes are stacked as a unit as in Fig. 6, where the inlet flow of the fluid to be heated takes place at 46 through the notch 46<SP>1</SP> in a flow tube 47 and proceeds longitudinally through a heating passage 48, crossing at the rear to a return passage 50 in the same tube, and then through cooperating notches to passage 52 in flow tube 51, returning through passage 53 and thence through the passages in the remaining tubes 54, 57, 61 and 64 to the outlet notch 67. The stacked unit is assembled against a front header 68, Fig. 10, and a rear header 71, :bleed holes 71<SP>1</SP> being provided in both headers, and is enclosed in a jacket 73 through which the heater tubes 30 pass to a junction box 77. The topmost flow tubes at the two sides connect with channel elements 72 (Fig. 7 not shown) which prevent direct flow between inlet and outlet, the fluid to be heated passing into the inlet connection 81, through the space 74, into the flow tubes in series as described above, and through the space 75 to the outlet port 83. In a modification, Fig. 12, the heater tube 30 is provided with fins 115, the flow tube 110 is circular, and the partitions 116 are resilient and curved in shape. In a further modification, Fig. 16, the fins are omitted, and resilient partitions 130 form a seal with the flow tube.