GB474576A - Improvements relating to continuous kilns - Google Patents

Abstract

474,576. Tunnel kilns. HARTFORD, F. M. Feb. 3, 1936, No. 3168. Convention date, April 13, 1935. [Class 51 (ii)] Hearths.-In an annular tunnel kiln, the hearth consists of segmental sections 28 carried by frames 27 which are freely supported on spaced carrier members 24, the latter being disposed beneath the abutting ends of adjacent sections 28. In the form shown in Figs. 2, 3, the carrier members 24 rest on circular rails 23 which, in turn, are supported by rollers 18 mounted in bearing brackets 20 adjustable in fixed base plates 21 ; transmission of heat to the rings 23 and rollers 18 is minimized by the provision, on the carriers 24, of upwardly projecting flanges 25 on which rest flanges 26 formed on the hearth frames 27. Figs. 4, 6 show a modification in which the carrier members consist of wheeled trucks 43 running on rails 42, the downward transmission of heat being in this case reduced by the provision of upstanding pads 44 on which the hearth frames 27a rest. The trucks 43 are attached by loose pins 46 to a driven circular H-section rail 47, set screws 50, bearing on tongues 48 secured to the trucks, being provided to permit the wheel axles 40 to be adjusted to their true radial positions in relation to the kiln. In both constructions, the spaces between the adjacent ends of adjoining hearth sections 28, 28a are sealed by gaskets 38. The invention is described as applied to a muffle-heated kiln having side heating-chambers D, Fig. 2, through which the gases from burners 12 flow in counter-current to the goods and. which diminish gradually in cross section in the direction of gas flow.