GB724072A - Improved watertube steam boiler - Google Patents

Abstract

724,072. Water-tube steam boilers. VORKAUF, H. Sept. 22, 1950 [June 25, 1949], No. 16918/49. Class 123 (2). A steam boiler comprises unheated downcomer tubes 1, Figs. 1 and 2, which are disposed at the four corners of a rectangular combustion chamber and are interconnected by lower headers 2, 2, 3, 3 and upper headers 4, 5, 5 between which extend steamgenerating tubes 6, 7, 9, 9 lining the front, rear and side walls, respectively, of the combustion chamber ; the lower headers 3 are connected to the water space of an associated steam-and-water drum 13 by pipes 14, and the upper headers 4, 5 to the steam space by pipes 15. As shown, the rear tubes 7 do not extend the whole height of the boiler, their upper ends being connected to the front tubes 6 by tubes 8 forming an inclined bank at the top of the combustion chamber, and a superheater 11 and economizer 12 are preferably fitted above said tube bank 8. Several modifications are described, but in each case the downcomers and interconnecting headers constitute a supporting structure for the steamgenerating tubes. Fig. 6, for example, shows a boiler comprising unheated corner downcomers 1d connected by lower and upper longitudinal headers 3d, 5d and lower and upper transverse headers 24, 25 and 4d, 27, the tubes 9d of the side walls extending between the headers 3d, 5d and the front wall tubes 6d between the headers. 24, 27 ; roof tubes 26 extend between the headers 27, 4d and the tube rows of a convection bank 8d between tubes 28 branching from the header 25 and said roof tubes. In another arrangement, Fig. 10, with corner downcomers 1h, the front and rear wall tubes 6h, 37 extend directly from the headers 24h, 25h, respectively, to the steam- and-water drum 13h and the side wall tubes 9h, as before, between the headers 3h, 5h ; in addition a convection steam-generating tube bank 38, located behind a convection superheater 36h, is provided in parallel with the tubes 37.