GB1209796A - Improvements in or relating to package type water tube boilers - Google Patents

Abstract

1,209,796. Gaseous fuel fired water tube boilers; superheaters. M. E. BOILERS Ltd. and E. C. RICHARDSON. 1 Jan., 1969 [29 Feb., 1968], No. 9913/68. Headings F4A and F4B. In a package type water tube boiler having an elongated combustion chamber 48 with burners 49 and 50 at opposite ends and a combustion gas outlet 22 intermediate its ends, water tubes 17 and 20 define two alternate paths for the gases at least one of which has a superheater 35 therein. Shutters 45 and 46 control the outlets 43 and 44 from the paths and thus the proportion of gases passing through each path. The tubes 17 and 20 extend between upper and lower drums (12 and 16), Figs. 2 and 3 (not shown), and the tubes 20 form a barrier which co-operates with a barrier formed by the centre portion of the inner row of the tubes 17 to define the two alternate flow paths. The gases flow through gaps 39 between the tubes 17 at the ends of the inner row and through the banks 41 and 42 of tubes 17 to the outlets 43 and 44. The steam produced in the tubes 17 and 20, tubes 26 extending between upper and lower headers 23 and 25 connected to the drums (12 and 16), Fig. 3, by means of pipes (24 and 27), and tubes (19) extending between the drums along the upper, lower and front walls of the boiler, is fed from the upper drum to a steam header 30. The header 30 is connected by a pipe 31 to a superheater inlet header pipe 32 connected by the superheater tubes 33 to the superheater outlet header 37. A superheater may be provided in each of the alternate paths. The burner 49 may be a coke oven gas burner and the burner 50 a blast furnace gas burner. Similar burners may be provided in the opposite end walls and more than one burner may be provided in each end wall. Water is fed to the upper drum (12), Fig. 2, through a pipe (13) with a control valve arranged to maintain a predetermined water level in the drum.