GB583103A - Improvements in tubular forced-flow boilers - Google Patents

Abstract

583,103. Forced-flow boilers. DANKS & CO., (OLDBURY), Ltd., E., and SMITH, J. June 26, 1944, No. 12091. [Classes 64 (i) and 123 (ii)] A forced-flow hot water, steam, &c., boiler comprises a casing 1 which encloses a combustion chamber 2 having successive upflow and downflow passes 3, 5, separated by a baffle 20, and a number of parallel-extending tubes 6 for the passage of water &c. from a bottom water header 7 to an upper water header or steam and water drum 8. Each tube 6 comprises a length 13 lining the forwardly-inclined rear wall 14 of the combustion chamber 2, two banks 10, 12 of series-connected lengths 9, 11 respectively, and a length 15 lining the top wall of the passes 3, 5, the bank 10 being located, as shown, within and across the upflow pass 3 and the bank 12 extending across both passes. The tubes 6 may be continuous between the two headers 7, 8 or, alternatively, some or all of them may be in two parts, connected by a header 18 provided with inspection openings. Preferably the topmost row of the lengths 9 is spaced sufficiently above the remaining lengths of the bank 10 to accommodate a soot blower adapted to be inserted through an opening or wall box 40; openings with doors 37, 38, 39 and 42 are also provided in the boiler casing to give access to the combustion chamber, &c. The baffle 20, which is inclined so that the gas flow area through the two passes 3, 5 is progressively reduced, extends from the wall 13 and is adapted to support the tube lengths 11. These tube lengths 11 are also supported by vertical bars 26, 28 welded to the return bends 19 thereof, the bars 26 depending from the tube lengths 15 and the bars 28 from an angle member 30 on the casing 1; similarly the tube lengths 9 are supported by bars 22 which depend from the lowermost tube lengths 11 and bars 24 welded to the headers 18 or the lowermost tube lengths 9, with the latter resting on the front wall 25 .of the combustion chamber. A hopper 33 provided with a door 34 for the removal of grit is disposed below the downflow pass 5.