Heat exchanger

Abstract

The present invention relates to a heat exchanger applied to a boiler, and an object of the present invention is to provide a heat exchanger that can improve heat transfer efficiency by reducing distance between the heat exchange pipes while making a heating water passage passing through heat exchange pipes be long, and can be easily manufactured. In order to achieve the heat exchanger, according to the present invention, 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, and 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. The first and second subsidiary plates are fixed to both ends of the heat exchange pipe units in order to maintain a distance between the plurality of heat exchange pipe units constant. The first and second end plates are fixed to the outer surfaces of the first and second subsidiary plates, respectively.

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; and   first and second end plates that are fixed to the outer surfaces of the first and second subsidiary plates, respectively.   
     
     
         2 . The heat exchanger according to  claim 1 , 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.   
     
     
         3 . The heat exchanger according to  claim 1 , 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. 
     
     
         4 . The heat exchanger according to  claim 2 , wherein the heating water inlet is formed through the first end plate, and
 the heating water outlet is formed through the second end plate.   
     
     
         5 . The heat exchanger according to  claim 2 , 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. 
     
     
         6 . The heat exchanger according to  claim 1 , wherein the cross-sections of the plurality of heat exchange pipes are formed so that a distance between the heat exchange pipes at the entrance of the combustion gas is large and a distance between the heat exchange pipes at the exit of the combustion gas is small. 
     
     
         7 . The heat exchanger according to  claim 3 , wherein the heating water inlet is formed through the first end plate, and
 the heating water outlet is formed through the second end plate.   
     
     
         8 . The heat exchanger according to  claim 3 , 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. 
     
     
         9 . The heat exchanger according to  claim 2 , wherein the cross-sections of the plurality of heat exchange pipes are formed so that a distance between the heat exchange pipes at the entrance of the combustion gas is large and a distance between the heat exchange pipes at the exit of the combustion gas is small. 
     
     
         10 . The heat exchanger according to  claim 3 , wherein the cross-sections of the plurality of heat exchange pipes are formed so that a distance between the heat exchange pipes at the entrance of the combustion gas is large and a distance between the heat exchange pipes at the exit of the combustion gas is small.