Transition assembly and method of connecting to a heat exchanger

Abstract

A transition assembly is provided for connecting a heat exchanger to an external flow path. The assembly includes a fluid connection tube and a transition tube. The ends of the fluid connection tube and the transition tube are sized such that one tube may be inserted within the other tube. A portion of the exterior tube may then be deformed to retain the interior tube. The ends may be shaped by conventional methods such as swaging.

1 . A transition assembly for connecting a heat exchanger to an external flow path, the assembly comprising: 
 a fluid connection tube extending from the heat exchanger, the fluid connection tube including a body extending from the heat exchanger having a first internal cross-sectional area and an extended end having a second internal cross-sectional area which is larger than the first internal cross-sectional area; and    a transition tube having a transition end, a coupling end and a body portion extending between the transition end and the coupling end, the body portion having a first external cross-sectional area and the transition end having a second external cross-sectional area which is larger than the first external cross-sectional area, the transition end fitting substantially within the extended end, an edge portion of the extended end being deformed to retain the transition end within the extended end.    
   
   
       2 . The transition assembly of  claim 1  wherein the fluid connection tube and the transition tube are brazed together with brazing material.  
   
   
       3 . The transition assembly of  claim 2  wherein the brazing material is located on the interior of the fluid connection tube.  
   
   
       4 . The transition assembly of  claim 1  wherein the fluid connection tube is made from aluminum and the transition tube is made from stainless steel.  
   
   
       5 . The transition assembly of  claim 1  wherein the edge portion is deformed in only one location to retain the transition end within the extended end.  
   
   
       6 . The transition assembly of  claim 1  wherein the entire edge portion is deformed to retain the transition end within the extended end.  
   
   
       7 . The transition assembly of  claim 1  wherein the body portion has a third internal cross-sectional area and the coupling end has a fourth internal cross-sectional area which is larger than the third internal cross-sectional area.  
   
   
       8 . The transition assembly of  claim 1  wherein the cross-sectional areas are circular.  
   
   
       9 . A heat exchanger comprising: 
 a pair of spaced, generally parallel headers;    a plurality of spaced, generally parallel tubes extending between and in fluid communication with the interior of the headers; and    a transition assembly including a fluid connection tube and a transition tube, the transition tube extending from one of the headers, the fluid connection tube including a body extending from the heat exchanger having a first internal cross-sectional area and an extended end having a second internal cross-sectional area which is larger than the first internal cross-sectional area, the transition tube having a transition end, a coupling end and a body portion extending between the transition end and the coupling end, the body portion having a first external cross-sectional area and the transition end having a second external cross-sectional area which is larger than the first external cross-sectional area, the transition end fitting substantially within the extended end, an edge portion of the extended end being deformed to retain the transition end within the extended end.    
   
   
       10 . The heat exchanger of  claim 9  wherein the fluid connection tube and the transition tube are brazed together with brazing material.  
   
   
       11 . The heat exchanger of  claim 10  wherein the brazing material is located on the interior of the fluid connection tube.  
   
   
       12 . The heat exchanger of  claim 9  wherein the fluid connection tube is made from aluminum and the transition tube is made from stainless steel.  
   
   
       13 . The heat exchanger of  claim 9  wherein the edge portion is deformed in only one location to retain the transition end within the extended end.  
   
   
       14 . The heat exchanger of  claim 9  wherein the entire edge portion is deformed to retain the transition end within the extended end.  
   
   
       15 . The heat exchanger of  claim 9  wherein the body portion has a third internal cross-sectional area and the coupling end has a fourth internal cross-sectional area which is larger than the third internal cross-sectional area.  
   
   
       16 . The heat exchanger of  claim 9  wherein the cross-sectional areas are circular.  
   
   
       17 . A method of manufacturing a transition assembly for connecting a heat exchanger to an external flow path, the assembly including a fluid connection tube and a transition tube, the fluid connection tube including a body and an extended end, the transition tube having a transition end, a coupling end and a body portion extending between the transition end and the coupling end, the method comprising the steps of: 
 inserting the transition end within the extended end of the fluid connection tube such that the transition end is substantially enclosed within the extended end;    deforming an edge of the extended end to retain the transition end within the extended end; and    brazing the assembly to create a substantially fluid tight connection between the fluid connection tube and the transition tube.    
   
   
       18 . The method of  claim 17  further comprising the step of inserting a brazing material within the extended end of the fluid connection tube prior to inserting the transition end.  
   
   
       19 . The method of  claim 18  wherein the step of inserting a brazing material includes inserting a brazing ring sized to fit within the extended end.  
   
   
       20 . The method of  claim 17  wherein the step of brazing the assembly is carried out via controlled atmosphere brazing.  
   
   
       21 . The method of  claim 17  wherein the transition tube is oriented in a downward direction relative to a gravitational force during the step of brazing the assembly.  
   
   
       22 . The method of  claim 17  further comprising the steps of providing the fluid connection tube with the body having a first internal cross-sectional area and the extended end having a second internal cross-sectional area and providing the transition tube with the body portion having a first external cross-sectional area and the transition end having a second external cross-sectional area which is larger than the first external cross-sectional area.  
   
   
       23 . The method of  claim 22  wherein the cross-sectional areas are circular.  
   
   
       24 . The method of  claim 17  further comprising the step of inserting an end of an external flow path within the coupling end of the transition tube to create a substantially fluid tight connection between the transition tube and the external flow path.