GB296147A - Improvements in or relating to water tube boilers - Google Patents

Abstract

296,147. Spearing, K. A. June 13, 1927. Water-tube boilers.- In a boiler having vertical tubes lining the walls of the combustion chamber and banks of tubes in the path of the gases from the combustion chamber to the outlet flue, all the tubes are so suspended from the upper part of the boiler free of the furnace walls or other supports as to permit longitudinal expansion of the tube. The firebrick side walls of the combustion chamber 1, Fig. 1, supported on cross bars carried by stanchions 10, 15 are lined with tubes 16 connected to upper header 17 resting upon the top of the walls and to lower headers 18 placed outside the hopper-shaped bottom of the chamber. The front wall 6 supported upon a cross bar 8 is similarly lined with tubes 19 which are connected to lower headers 21 and which serve to support, at their lower portions, the refractory lining 22 of the front of the hopper bottom. Tubes 23 at the back of the combustion chamber are connected to an upper header 24 suspended from the boiler framework and support the lining at the back of the hopper bottom. The headers 20, 24 are connected to the steam drum 28 by tubes 29, 27, and the headers 17 open into the drum directly. A bank of tubes 31 extend from the drum through the vertical flue 4 to a water drum 32. Water is supplied to the lower headers from the upper or lower drum through flexibly connected pipes 34, 35. Sand seals 37 are provided at the junction of the hopper bottom with the ash pit 3. A superheater 39 is placed between the tubes 31. In a boiler having a bank of tubes 60, Fig. 3, arranged above the combustion chamber and connected at the front and back to vertical headers 61, 62, the tubes 41 lining the sides of the chamber are connected to upper headers 43 suspended by adjustable stays 45. The upper header 49 of the tubes lining the rear wall rests upon the tubes 64 connecting the headers 61 to the steam drum 70. The headers 61 are suspended by stays 50. The steam passes through a superheater 73 in the uptake and then through a superheater 75 forming part of the lining the rear wall of the combustion chamber. The tubes lining the front wall open directly into the steam drums.'