| 摘要 |
<p>PURPOSE:To obtain the titled boiler of excellent efficiency in which no rust occurs, the durability thereof is excellent and which is affluent in heat insulation and requires no special heat insulating structure by forming a boiler drum having therein a flue by concrete. CONSTITUTION:A boiler 1 is made up of a concrete cylindrical body 2 forming a semiarcuate shape at its upper part, and concrete end plates 3 and 3 which are fixed to both end surfaces of the cylindrical body 2 and block both opening parts. The inner peripheral side and the outer peripheral side of the joint surface between the end plate 3 and the cylindrical body 2 are caulked and a resin is poured into the joint surface to keep a water tightness. Further, concrete is made into sufficient tightness so that it can be water tight with respect to a high pressure. A flue 4 is arranged in a substantially U-shape parallel at the upper and lower parts in the lateral direction by a cylindrical body having a rectangular section. The upper flue 4a communicates with an exhaust part on the outside of the boiler drum 1. Further, any danger the to the three-dimensional expansion of hot water within the boiler drum 1 is positively prevented by an expansion pipe 24.</p> |
