2-pass heat exchanger including thermal expansion joints

Abstract

A heat exchanger ( 10 ) is provided and in a highly preferred form is an EGR cooler ( 52 ) having first and second passes ( 56 A, 56 B) that are connected to an inlet/outlet manifold ( 70 ) by a pair of corresponding thermal expansion joints ( 87,93 ) to allow differential thermal expansion between the various structural components of the heat exchanger ( 10 ).

1 . An exhaust gas cooler for use in an engine system, comprising:
 a coolant housing including:
 a first end having at least one first end opening, 
 a second end having at least one second end opening; 
 a coolant chamber between the first end and the second end, and 
 at least one coolant port to the coolant chamber, and 
   an exhaust gas turning manifold attached to the second end and including at least one turning manifold opening in fluid communication with the coolant housing;   first and second exhaust gas cores attached to a common header plate, the first exhaust gas core having a first plurality of tubes with inlet ends attached to the common header plate and outlet ends attached to a first transition piece, the second exhaust gas core having a second plurality of tubes with outlet ends attached to the common header plate and inlet ends attached to a second transition piece; and   thermal expansion joints located at each of the transition pieces to provide a seal at or near the second end and to allow the exhaust gas cores to move relative to each other and the coolant housing,   wherein the first and second exhaust gas cores are jointly inserted into the coolant chamber and fastened to the coolant housing by the mounting header, so that the first and second transition pieces are supported at thermal expansion joints at or near the second end.   
     
     
         2 . The exhaust gas cooler of  claim 1 , the at least one second end opening including a first second end opening and a second end opening, each receiving one of the transition pieces of the first and second cores. 
     
     
         3 . The exhaust gas cooler of  claim 2 , the first second end opening and a second second end opening each including one of the thermal expansion joints. 
     
     
         4 . The exhaust gas cooler of  claim 3 , wherein the thermal expansion joints are O-rings. 
     
     
         5 . The exhaust gas cooler of  claim 1 , the at least one turning manifold opening including a first turning manifold opening and a second turning manifold opening, each receiving one of the transition pieces of the first and second cores. 
     
     
         6 . The exhaust gas cooler of  claim 5 , the first and second turning manifold openings each including one of the thermal expansion joints. 
     
     
         7 . The exhaust gas cooler of  claim 6 , wherein the thermal expansion joints are O-rings. 
     
     
         8 . The exhaust gas cooler of  claim 1 , the at least one second end opening including a first second end opening and a second second end opening and the at least one turning manifold opening including a first turning manifold opening and a second turning manifold opening, the first second end opening, the second second end opening, the first manifold opening, and the second manifold opening, each receiving a portion of one of the transition pieces of the first and second cores. 
     
     
         9 . The exhaust gas cooler of  claim 8 , the first second end opening, the second second end opening, the first manifold opening, and the second manifold opening, each further including a thermal expansion joint. 
     
     
         10 . The exhaust gas cooler of  claim 1 , the coolant chamber further including a first coolant channel and a second coolant channel wherein the first exhaust gas core is inserted into the first coolant channel and the second exhaust gas core is inserted into the second coolant channel. 
     
     
         11 . The exhaust gas cooler of  claim 10 , the first and second coolant channels being fluidically separate and containing fluids at different temperatures. 
     
     
         12 . The exhaust gas cooler of  claim 1 , the first transition piece including a first core header attached to the outlet ends of the first plurality of tubes and the second transition piece including a second core header attached to the inlet ends of the first plurality of tubes. 
     
     
         13 . The exhaust gas cooler according to  claim 1 , wherein the thermal expansion joints are ring-shaped, and each of the at least one turning manifold openings receives at least one of the thermal expansion joints. 
     
     
         14 . The exhaust gas cooler according to  claim 1 , wherein the thermal expansion joints are ring-shaped, and each of the at least one second end openings receives at least one of the thermal expansion joints. 
     
     
         15 . The exhaust gas cooler according to  claim 1 , the header plate further including the at least one coolant port. 
     
     
         16 . The exhaust gas cooler according to  claim 15 , wherein the header plate coolant port is a coolant outlet. 
     
     
         17 . An exhaust gas cooler for use in an engine system, comprising:
 a coolant housing including:
 a first mounting side, 
 a second turning side, 
 a coolant chamber extending between the first mounting side and the second turning side, 
 at least one coolant chamber opening extending from the coolant chamber to the second turning side, 
 at least one coolant inlet port to the coolant chamber, and 
 at least one outlet port from the coolant chamber; 
 a turning manifold including at least one turning manifold opening and attached to the second turning side of the coolant housing; 
   an exhaust gas core including a mounting header; and   a seal at the end of the exhaust gas core opposite the end with the mounting header,   wherein the mounting header is fastened to the coolant housing at the mounting side, such that the core is inserted through the coolant chamber, the core is supported by the seal at the second turning side, the core is movable at the second turning side relative to the coolant housing, and the seal creates a fluid seal at the second turning side.   
     
     
         18 . An exhaust gas cooler for use in an engine system, comprising:
 a coolant housing including:
 a first end, 
 a second end, 
 a coolant chamber including first and second channels extending between the first end and the second end, 
 first and second openings extending from the first and second channels to the second end, each opening including a seal groove containing an O-ring seal, and 
 a coolant inlet port to the first channel, a coolant outlet port from the first channel, a coolant inlet port to the second channel, and a coolant outlet port from the second channel; 
   a turning manifold attached to the second end of the coolant housing; and   first and second exhaust gas cores each attached to a common mounting header,
 the first exhaust gas core including a first plurality of tubes having an inlet end attached to the mounting header and an outlet end having a first transition portion including a first header plate attached to the outlet end of the first plurality of tubes and further including a first extension portion extending from the first header plate, and 
 the second exhaust gas core including a second plurality of tubes having an outlet end attached to the mounting header and an inlet end having a second transition portion including a second header plate attached to the inlet end of the second plurality of tubes and further including a second extension portion extending from the second header plate; 
 wherein the first exhaust gas core is inserting into one of the coolant channels and the second exhaust gas core is inserted into the other coolant channel, the first extension is slidably inserted into one of the first and second openings at the second end of the coolant housing such that the first extension makes a fluid seal with the opening and can move relate to the opening, the second extension is slidably inserted into the other of the first and second openings at the second end of the coolant housing such that the second extension makes a fluid seal with the other opening and can move relate to the other opening, the mounting header is fastened to the first end of the coolant housing, and wherein the turning manifold is fluidly connected to the first plurality of tubes and the second plurality of tubes. 
   
     
     
         19 . The exhaust gas cooler of  claim 18 , the first and second coolant channels being fluidically separate and containing fluids at different temperatures. 
     
     
         20 . A method of producing an exhaust gas cooler for use in an engine system, comprising:
 forming a coolant housing having a first end, a second end, and two coolant channels between the first end and the second end, the first end further including two first end openings to each of the coolant channels and the second end further including two second end openings to each of the coolant channels;   inserting thermal expansion joints through each of the second end openings, such that the thermal expansion joints are disposed in each of the second end openings;   forming a turning manifold;   forming a first exhaust gas core having a plurality of first core tubes and a first transition piece and a second exhaust gas core including a plurality of second core tubes and a second transition piece;   attaching inlets of the of the first core tubes and outlets of the second core tubes to a common header plate;   inserting the assembly of the first core and the second core into the coolant housing such that the first core tubes and the second core tubes are each disposed within one of the coolant channels, the first transition piece and the second transition piece are each disposed within one of the second end openings and sealed by the thermal expansion joints, and the common header plate is attached to the first end of the coolant housing; and   attaching the turning manifold to the second end of the coolant housing such that the turning manifold is in fluid communication with each of the first core tubes and the second core tubes.