GB594389A - Improvements in or relating to vapour generating and heating units - Google Patents

Abstract

594,389. Water tube steam boilers etc.; steam superheaters. BABCOCK & WILCOX, Ltd., and ZOLLER, R. E. July 6, 1945, No. 17272. [Classes 123 (ii) and 123 (iii)] A steam &c. boiler comprises separate adjustably-fired furnaces 1, 7, Fig. 1, associated respectively with an inclined bank 2 of water tubes, extending between upper and lower drums 3, 4, and a superheater 15, with the outlet from the furnace 7 being in communication with the furnace 1 through a passage 18 and also in direct communication with the boiler flue uptake 9 through a by-pass 8 controlled by a damper 10 which is operated to close the by-pass during ahead operation and open it during manoeuvring. The superheater 15 is screened by a group of water tubes 16, and economizers and/or air heaters 14, 22 are provided in the uptake 9 and in an adjacent part 8<1> of the bypass 8. In a modified construction, Fig. 2, a reheater 23 is disposed across the outlet from the furnace 7 and a superheater 24 in the passage 18<1> between the two furnaces, both 23, 24 being screened by water tubes 25. During ahead operation the steam pressure and degree of reheat are controlled by the rates of firing the furnaces 1. 7 respectively and the degree of superheat by adjustment of the damper 10; during manoeuvring the furnace is shut down.