GB825250A - Improvements relating to the construction of open-hearth furnaces and other similar metallurgical furnaces - Google Patents

Abstract

825,250. Furnace walls and roofs. HEUER, R. P. Nov. 1, 1957 [Nov. 6, 1956], No. 34219/57. Class 51 (2). An open hearth furnace comprises a front wall 25 and back wall 26 suspended from buckstays 52 and arched inwardly towards a gabled roof 27 suspended from I-beams 35 hooked by brackets 36 on to front and back beams 32 and 33 respectively, the maximum width between the front and back walls at the upper hearth level 22 being more than 10% greater than the width of the roof at its inner face. The basic refractory roof bricks 46, Fig. 3, are suspended in pairs from the webs of beams 35 by hangers 38 with cardboard or asbestos expansion plates 51 between the bricks. Projections 40 on the hangers 38 engage co-moulded sockets 42 set towards one brick face at an angle, Fig. 2 (not shown), so that the bricks take up the slope of the roof suspended from the vertical hangers. The roof may be removed by crane and the beams 32 and 33 are supported on a hearth frame or beam structure 34. Metallic abutments 50 at the ends of the beams 35 engage the end roof bricks. The walls 25 and 26 comprise wedge-shaped basic bricks 53, Fig. 5, suspended by hangers 64 from buck-stays 52 spaced longitudinally of the furnace on the frame 34, and partly supporting the beams 32, 33. Intermediate bricks 54 filling the spaces between bricks 53 are of opposite wedge-shape to the latter and thus do not tend to fall inwardly of the furnace wall. These bricks 54, Fig. 10, have a metal casing comprising a U-plate 73 and a flat plate 76 each formed with internal ribs 72, and similar plates may be fitted to the bricks 53. The furnace walls may be planar instead of arched. In a modification, Fig. 11 (not shown), the wall bricks may be suspended from the buck-stays 52 by hooks engaging rods welded to said buck-stays. The gaps 91 between the roof and the walls may be closed by a mass of granular plastic refractory 92. Above the water-cooled door frames 93 in the front wall 25 are arches 94 of basic refractory, wedge bricks suspended from girders 95 in pairs by hangers 96. The bricks are metalcased with internal ribs similar to the bricks 54, Fig. 15 (not shown). The brickwork may comprise magnesia plus 5-75% chromite.