GB868929A - Improvements in or relating to tube walls - Google Patents

Abstract

868,929. Furnace walls. BABCOCK & WILCOX Ltd. Aug. 30, 1957 [Aug. 31, 1956], No. 27410/57. Class 51 (1). [Also in Group XIII] A gas-tight furnace wall panel comprises finned tubes 1, Fig. 1, welded edge-to-edge along the fins 2, 3. In an alternate construction the fins are tangentially arranged relative to the associated tubes. In the construction of a furnace chamber, welded U -shaped expansionmembers such as 17, Fig. 4, may be used to connect adjacent panels 10, 15, a welded finned tube 21 connecting panels at the chamber corners. Corners may also be constructed by cutting away in a suitable pattern fin parts from a panel such as 26, Fig. 6, and forming apertures in another panel 25 to accommodate the tubes 27 of the panel 26. These tubes may be welded at 28 to stub tubes 33 protruding from a header 32 and the abutment between the panels may be sealed by welding. In a boiler or heat exchanger of the " flame return " type having in a horizontal cylindrical casing 40, Figs. 7, 8, burners 41, 42, projecting flames into an internal duct 43, the latter is formed by curved tube walls 44, 45, which lead from a lower water drum 47 to an upper steam and water drum 46 and consist of finned tubes welded side-by-side along the edges of the fins. After traversing the duct 43 the hot gases reverse and pass through an annular duct 48 surrounding the duct 43 and containing evaporator tube nests 49, 51, and superheater tube nests 55 and 50. The nest 51 contains evaporator tubes 52 leading between the drum 47 and a chamber 53 leading to the drum 46. Steam from this drum is conducted to the superheater 55 through a header 56. Except for the portions opposite the superheater tubes 50, 55, which are formed of refractory 59, the outer wall of the duct 48 is also formed from welded sideby-side finned tubes.