Heat exchanger

Abstract

A heat exchanger applied to a boiler that can improve heat transfer efficiency by reducing the distance between the heat exchange pipes while making a long heating water passage through heat exchange pipes, which can be easily manufactured. Additionally, the heat exchanger includes a heat exchange device, first and second subsidiary plates, and first and second end plates. The heat exchange device includes a plurality of heat exchange pipe units through which heating water passes and which are spaced apart from each other at regular intervals. The heat exchange pipe units are provided between a heating water inlet and a heating water outlet, and are formed of pipes having a rectangular cross-section of which a side coming in contact with the combustion gas has a width large than the height.

1 . A heat exchanger comprising:
 a heat exchange device including a plurality of heat exchange pipe units through which heating water passes and which are spaced apart from each other at regular intervals, the heat exchange pipe units being provided between a heating water inlet and a heating water outlet, and being formed of pipes having a rectangular cross-section of which a side coming in contact with the combustion gas has a width large than a height;   first and second subsidiary plates to which both ends of the heat exchange pipe units are fixed to constantly maintain a distance between the plurality of heat exchange pipe units;   first and second end plates that are fixed to the outer surfaces of the first and second subsidiary plates, respectively;   wherein pipe insertion holes are formed through the first and second subsidiary plates in a longitudinal direction of the first and second subsidiary plates,   both ends of the plurality of heat exchange pipe units are fitted into the pipe insertion holes,   
       and
 both ends of the heat exchange pipe units, first and second subsidiary plates, and first and second end plates are fixed by brazing welding, respectively; and 
 wherein the heating water inlet is formed at the heat exchange pipe unit into which heating water flows, and the heating water outlet is formed at the heat exchange pipe unit from which heating water flows. 
 
     
     
         2 . A heat exchanger comprising:
 a heat exchange device including a plurality of heat exchange pipe units through which heating water passes and which are spaced apart from each other at regular intervals, the heat exchange pipe units being provided between a heating water inlet and a heating water outlet, and being formed of pipes having a rectangular cross-section of which a side coming in contact with the combustion gas has a width large than a height;   first and second subsidiary plates to which both ends of the heat exchange pipe units are fixed to constantly maintain a distance between the plurality of heat exchange pipe units;   first and second end plates that are fixed to the outer surfaces of the first and second subsidiary plates, respectively;   wherein the plurality of heat exchange pipe units forms a series of flow passages of which flow directions are alternately changed in opposite directions while the heating water, which flows from the heat exchange pipe unit provided at one end, flows to the heat exchange pipe unit provided at the other end; and   wherein the heating water inlet is formed at the heat exchange pipe unit into which heating water flows, and the heating water outlet is formed at the heat exchange pipe unit from which heating water flows.