F22B17/00—Water-tube boilers of horizontally-inclined type, i.e. the water-tube sets being inclined slightly with respect to the horizontal plane
F22B17/02—Water-tube boilers of horizontally-inclined type, i.e. the water-tube sets being inclined slightly with respect to the horizontal plane built-up from water-tube sets in abutting connection with two header boxes in common for all sets, e.g. with flat header boxes