GB740132A - Improvements in and relating to steam generators - Google Patents

Abstract

740,132. Supporting water-tube steam boilers. FOSTER WHEELER, Ltd. May 11, 1954 [May 11, 1953], No. 13748/54. Class 123(2). A water-tube steam boiler comprises a furnace chamber 16 which is separated by a throat 19 from an ash collecting chamber 21, the side walls 14, 15 and front and rear walls 12, 13 of the furnace and ash chamber being lined with steam generating tubes which extend continuously from a water drum 31 which is housed in a refractory block 20 forming the base of chamber 21 to an upper steam and water drum 27. The furnace is fired by pulverised fuel burners 17, the combustion gases flowing through openings at the end of the furnace into two lateral return passes 42 located one on each side thereof and leading to stacks 50. Each pass 42 houses a superheater 46 and is lined with steam generating tubes 44 extending between an intermediate header 45 and the drum 27, the headers also being connected to water drum 31 by water tubes 48. The narrow throat 19 shields the ash collecting in chamber 21 from the radiant heat of the furnace and thus prevents slagging, the ash being withdrawn periodically through a door 26. To obviate cracking of the refractory of the ash chamber due to expansion and contraction movements of the steam generating tubes the furnace and chamber are suspended from drum 27 by means of the tubes so that the structure expands and contracts as a unit. The drum 27 is supported on girders 28 resting on columns 29. An additional support for the ash chamber, which does not interfere with its vertical movement, is provided by a row of springs 32 which exert an upward pressure on the drum 31.