Boiler

Abstract

Provided is a boiler including: a plurality of heat transfer tubes arranged to form a cylindrical shape between an upper header and a lower header to constitute a heat transfer tube row; and a plurality of longitudinal fins provided to close gaps between the heat transfer tubes without connecting the adjacent heat transfer tubes, the plurality of longitudinal fins being provided to a portion other than one of one end in a vertical direction of the heat transfer tube row and a part in a peripheral direction thereof.

1 . A boiler comprising:
 a plurality of heat transfer tubes arranged to form a cylindrical shape between an upper header and a lower header to constitute a heat transfer tube row; and   a plurality of longitudinal fins provided to close gaps between the plurality of heat transfer tubes without connecting the adjacent heat transfer tubes, the plurality of longitudinal fins being provided to a portion other than one of one end in a vertical direction of the heat transfer tube row and a part in a peripheral direction thereof.   
     
     
         2 . A boiler according to  claim 1 , wherein:
 the heat transfer tube row comprises, in order to close gaps between each of the plurality of heat transfer tubes and the heat transfer tubes adjacent to both sides thereof, a plurality of double-fin heat transfer tubes each having the longitudinal fins on both sides thereof and a plurality of no-fin heat transfer tubes free from having the longitudinal fin;   the plurality of double-fin heat transfer tubes and the plurality of no-fin heat transfer tubes are alternately arranged one by one; and   the boiler further comprises a combustion chamber on an inner side of the heat transfer tube row, which communicates with a combustion gas flow path on an outer side of the heat transfer tube row through a portion free from having the longitudinal fin at the one end in the vertical direction of the heat transfer tube row.   
     
     
         3 . A boiler according to  claim 1 , wherein:
 the heat transfer tube row comprises, in order to close gaps between each of the plurality of heat transfer tubes and the heat transfer tube adjacent to one side thereof, a plurality of single-fin heat transfer tubes each having the longitudinal fin on one side thereof; and   the boiler further comprises a combustion chamber on an inner side of the heat transfer tube row, which communicates with a combustion gas flow path on an outer side of the heat transfer tube row through a portion free from having the longitudinal fin at the one end in the vertical direction of the heat transfer tube row.   
     
     
         4 . A boiler according to any one of  claims 1  to  3 , wherein the plurality of longitudinal fins have a size achieving closure of gaps between the adjacent plurality of heat transfer tubes owing to thermal expansion by one of a combustion gas and an exhaust gas. 
     
     
         5 . A boiler comprising:
 a plurality of heat transfer tubes arranged adjacent to each other; and   a longitudinal fin provided between the adjacent heat transfer tubes, wherein:   one end of the longitudinal fin is fixed to one of the adjacent heat transfer tubes; and   another end of the longitudinal fin abuts on another of the adjacent heat transfer tubes owing to thermal expansion by combustion of a fuel in a combustion chamber.