GB1366515A - Tubular vapour generating units - Google Patents

Abstract

1366515 Steam generators BABCOCK & WILCOX Ltd 25 Nov 1971 [25 Nov 1970] 54896/71 Heading F4A A tubulous forced flow once-through topsupported vapour generator has a convention heat exchange pass 2 with upright gas tight walls 5 formed by evaporator tubes welded together and hung from supporting steelwork 3 which also carries support tube lengths 12, 13 for tube banks 10 extending across the pass and connected to external headers 6, 11, the tube length 11 being connected for fluid flow in parallel with the tubular walls 5. The tubular walls 4 of a brown coal fired combustion chamber 1 are connected to an intermediate header 6 which supplies a steam/water mixture to the walls 5 and the support tube lengths 12, 13. The tubes of wall 5 are connected in eight parallel flow circuits to upper headers 7, 8 and the support tube lengths are connected to four headers 15. The headers feed four steam separators (9, Fig. 2, not shown), Tube banks 10 which may be used for feed water heating or steam heating, are welded at 14 to the tubular walls 5 and connected to their external headers 11 carried by the tube lengths 13 which are at the same temperature as the walls so as to reduce stresses at the joints 14.