GB861274A - Improvements in waste-heat vapour generators - Google Patents

Abstract

861,274. Waste-heat boilers; superheaters. BABCOCK & WILCOX CO. June 17, 1959 [June 23, 1958], No. 20731/59. Classes 123(2) and 123(3) A compact and wholly shop-assembled waste-heat boiler unit 10 which can be readily transported as a complete unit comprises a setting having upper, lower, and side walls 11, 12, 13 which define a horizontal gas pass 14 in the central part of which is located a bank of upright steam generating tubes 20 connected between an upper steam and water drum 18 and a lower water drum 19, superheater and economizer tube banks 22, 21, each composed of a number of transverse return-bent tubes, being accommodated in the gas pass upstream and downstream respectively of the steam generating tubes 20. The entire unit is base-supported on a rectangular frame 23 which is composed of channel members 24, 25 and has cross ties 26 with cradles 26A to support the lower drum 19. Pairs of brackets 27, 28 extend outwardly from the ends of the drum 19 and support transverse beams 29 which carry the lower transverse members 30 of rectangular frames which have side and upper members 30A, 30B and define the gas inlet and outlet openings of the gas pass 14. The side walls 13 of the pass 14, lined with insulating material 31A, extend between the upright frame members 30A, the upper drum 18 being supported by pairs of plates 32, 33 which are welded to opposite ends of the drum and extend outwardly and downwardly to engage the upper frame members 30B. Shelves 37E, 37S, overhanging the ends of the lower drum 19 to carry respectively the economizer 21 and the superheater 22, are supported by the cross-beams 29 and short side members 36 each of which is supported at one end on the adjacent end of the corresponding cross-beam 29 and has its other end resting upon a bracket 35 welded to the corresponding side of the drum 19. Vertical inlet headers 21A, 22A and outlet headers 21B, 22B for the economizer and superheater units 21, 22 respectively are attached by ties 44 and 38 to the corresponding vertical frame members 30A. Each tubular economizer element 45 connected between the headers 21A, 21B comprises five longitudinally disposed multiloop tube layers which are connected in series and which have a direction of throughflow of working medium which is alternately cross-counter and cross-parallel with respect to the flow of gas in the pass 14. The layers of economizer tubes are supported one upon another at each side of the pass 14 by two tiers of notched spacing bars 42 extending between the layers of tubes, the bars 42 of each tier, fixed at one end only to a bar 43 connected between the corresponding upper and lower frame members 30B, 30, having their free ends protruding between the rearmost row of steam generating tubes 20A. The tubes of the superheater bank 22, each of which comprises sinuous, horizontally disposed return-bend elements connected between the headers 22A, 22B, are supported in a similar manner. The unit is provided with shipping stirrups welded to the sides of the lower drum 19 and with lifting lugs connected to the upper drum 19.