| 摘要 |
The present invention relates to a once-through boiler, and more specifically, to a once-through boiler with multiple water pipes for generating hot water or steam. The once-through boiler comprises: an upper header (12a) and a lower header (12b) installed on an upper and a lower portion in a casing and vertically separated from each other; and an inner water pipe array (14) and an outer water pipe array (20) connected to form a combustion gas passage (21), wherein a plurality of inner and outer vertical water pipes (13, 19) are concentrically arranged between the upper header (12a) and the lower header (12b). A spacer (16) is inserted on the inner vertical water pipe (13) to form a combustion flame passage between the inner vertical water pipes (13). The outer vertical water pipes (19) having a smaller diameter than the inner vertical water pipes (13) are arranged on the outside of the inner vertical water pipes (13). An insulation member (23) between the outer vertical water pipes (19) comes in surface contact with adjacent outer vertical water pipes (19), and is inserted between the outer vertical water pipes (19) to form a discharge gas passage (24) between the outer vertical water pipes (19) to discharge combustion gas flowing into the combustion gas passage (21) through the discharge gas passage (24). |
