GB827882A - Improvements relating to tubulous heat exchange apparatus - Google Patents

Abstract

827,882. Water-tube steam boilers; superheaters. BABCOCK & WILCOX Ltd. Dec. 20, 1956 [Dec. 21, 1955], No. 38877/56. Classes 123(2) and 123(3) In a boiler comprising a furnace 14 lined with steam generating tubes and fired by burners 16, combustion gases leaving the furnace through a horizontal pass locating a secondary superheater 30, a reheater 32 and a primary superheater 10, the latter is constructed on site from prefabricated tube platens of the form shown in Fig. 2. Each platen consists of eight multiple-bend nested tubes the inlet and outlet portions 102, 120 of which are disposed in a single straight row so that they may pass between tubes 26 lining the roof of the horizontal pass. The portions 102, 120 are welded to junction headers 100, 122 respectively. Below the roof of the pass four of the nested tubes are displaced a short distance from the plane of the portions 102, 120 so that each ulaten consists of two rows of parallel tubes. To complete the superheater, the shop-fabricated platens each comprising the multiple bend tubes and associated junction headers are assembled side-by-side on site. The ends of each of the junction headers 100, 122 are then connected by welded tubes 96, 98 and 124, 126 respectively to main inlet and outlet headers 94, 128 which are disposed transversely above the associated rows of junction headders and the complete unit elevated to its operative position and secured to the appropriate steelwork. The intermediate upper return bends 182, 186 (Fig. 6) of each platen are suspended from the tubes 26 by a bolt 190 connected to welded-on plates 180, 184 by a rod 188 whilst the platen tubes are held at their correct spacing by intertube clevis components 160, 162, 164, 166 shown in Fig. 7. Specification 526,825 is referred to.