Short shell highly insulated converter

Abstract

A short shell highly insulated converter includes a short shell forming a generally tubular body for housing a catalyst substrate. End cones having a wide-open end and a narrow open end comprise an inner wall forming a first opening at the wide-open end for engaging the catalyst substrate. The end cones further comprise an outer wall extending beyond the inner wall to form a second wider opening at the wide-open end for engaging the short shell. The inner wall and outer wall converge at the narrow open end to form a snout. A full-length insulating layer is disposed adjacent the catalyst substrate and is selected based upon the amount of overlap between the end cone and the catalyst substrate, the full-length insulating layer being substantially co-extensive with the catalyst substrate. A partial length insulating layer is disposed between the inner insulating layer and the short shell, the partial length insulating layer being generally co-extensive with the short shell. The highly insulated catalytic converter has a shortened shell and tailored insulating layers, providing a shorter package with stronger end cones that are robust to axial and bending stresses.

1 . A highly insulated short shell catalytic converter comprising: 
 a short shell forming a generally tubular body for housing a catalyst substrate, said short shell having a length that is less than that of said catalyst substrate;    an end cone disposed on each end of said tubular body, said end cone having a wide open end and a narrow open end;    said end cone comprising an inner wall forming a first opening at said wide open end for engaging a catalyst substrate and an outer wall extending beyond said inner wall to form a second wider opening at said wide open end for engaging said short shell;    said inner wall and said outer wall converging at said narrow open end to form a snout;    a full-length insulating layer disposed adjacent said catalyst substrate; and    a partial length insulating layer disposed between said said full-length insulating layer and said short shell, said partial length insulating layer being generally co-extensive with said short shell.    
     
     
         2 . The highly insulated short shell catalytic converter of  claim 1 , wherein said full-length insulating layer is tailored based upon overlap of said end cone inner wall with said catalyst substrate and is generally substantially coextensive with said catalyst substrate.  
     
     
         3 . The highly insulated short shell catalytic converter of  claim 1 , further comprising: 
 an end cone insulation disposed between said inner wall and said outer wall in a gap formed by said inner and outer walls at said wide-open end of said end cone.    
     
     
         4 . The highly insulated short shell catalytic converter of  claim 1 , wherein said converter is prepared by stuffing said catalyst substrate, said full-length insulating layer, and said partial length insulating layer into said short shell.  
     
     
         5 . The highly insulated short shell catalytic converter of  claim 1 , wherein said converter is prepared by stuffing said catalyst substrate, said full-length insulating layer, and said partial length insulating layer into an oversized shell and sizing down said oversized shell onto said insulated catalyst substrate.  
     
     
         6 . A method for preparing a highly insulated short shell catalytic converter comprising: 
 providing a short shell forming a generally tubular body for housing a catalyst substrate, said short shell having a length that is less than a length of said catalyst substrate;    disposing an end cone on each end of said tubular body, said end cone having a wide-open end and a narrow open end;    said end cone comprising an inner wall forming a first opening at said wide open end for engaging a catalyst substrate and an outer wall extending beyond said inner wall to form a second wider opening at said wide open end for engaging said short shell;    said inner wall and said outer wall converging at said narrow open end to form a snout;    disposing a full-length insulating layer adjacent said catalyst substrate; and    disposing a partial length insulating layer between said full-length insulating layer and said short shell, said partial length insulating layer being generally co-extensive with said short shell.    
     
     
         7 .The method of  claim 6 , further comprising: 
 disposing an end cone insulation between an inner wall and said outer wall in a gap formed by said inner and outer walls at said wide-open end of said end cone.    
     
     
         8 . The method of  claim 6 , wherein said converter is prepared by stuffing said catalyst substrate, said full-length insulating layer, and said partial length insulating layer into said short shell.  
     
     
         9 . The method of  claim 6 , wherein said converter is prepared by stuffing said catalyst substrate, said full-length insulating layer, and said partial length insulating layer into an oversized shell and sizing down said oversized shell onto said insulated catalyst substrate.