GB1172122A - Furnace Structure - Google Patents

Abstract

1,172,122. Blast furnace supports; platforms. HEAD WRIGHTSON & CO. Ltd. 9 Jan., 1967 [17 Jan., 1966], No. 1151/67. Heading F4B. All or a considerable fraction of the weight of a blast furnace is taken by a generally rectangular frame 12, surrounding and spaced from the furnace above a bush ring 13, said frame being supported by a leg 14 at each corner engaging foundation members 15 set in the earth. The frame 12 comprises deep I-section girders 38, eight connector members 43 disposed equiangularly about a vertical axis A and connected as by welding or bolting to the web of each associate I-beam and the furnace shell 6. Associated with the top and bottom of each of the members 43 are structural rings 45 and 13 fixed to the furnace shell. A compression ring member 51 in the form of a regular octagon welded to the top flanges 40 of the girders 38 has internally-extending projections welded to members 43. An auxiliary frame member 23 has legs 24 connected to the frame 12, said legs carrying working platforms 25 and 26. Pairs of divergent turn-buckles 56 extend between the furnace shell 6 and girders 59 forming the top of auxiliary frame 23. Similar turn-buckles extend between the furnace shell and the frame 12. The bottom portion 62 of the hearth 9 is semi-ellipsoidal in shape and of circular cross-section. It is lined with carbon bricks 64 which extend upwardly to meet the shaft lining 61 which incorporates conventional cooling plates. The legs 14 and girders 38 are prestressed so that when subject to their full load they will be straight. This is achieved by bowing girders 38 upwardly and drawing the lower ends of legs 14 radially outwardly and holding them in such a position as to allow said lower ends to rotate freely without subjecting them to bending moments. To this end a metal base 66, Fig. 7, is bolted to each foundation member 15 and is normal to the leg axis B when the leg is straight. An adjustable member 67 rests on member 66 and is formed with an annular groove 68 engaged by a flange 77 on a casting 75 forming the bottom of the leg. Groove 68 and flange 77 have mating part spherical seatings 71 and 76 of hardened metal. Each member 67 has lugs 78 connected by a draw bolt 79 to a lug 81 fixed to the base, so that by tightening nuts 82 on the bolts 79 each leg can be moved to its prestressed position. Each leg is filled with concrete 121 which may incorporate steel reinforcements 122. In a modification, Fig. 9 (not shown), the hearth is supported by a foundation set in the ground. The connector members from the girders 38 may be attached to flanges on the furnace shell which is cooled by vertical elongated cooling plates (102, 103) and by conventional cooling plates in the bush area, Fig. 10 (not shown). In a similar construction, Fig. 11 (not shown), the whole wall is cooled by conventional cooling plates.