Rocket engine having a transition attachment between a combustion chamber and an injector

Abstract

A rocket engine has a combustion chamber, an injector, and an attachment between the combustion chamber and the injector. The attachment includes an annular metallic deposit joined to the chamber wall outer surface, and an annular transition ring structure. The transition ring structure has an annular step collar, and an annular adaptor ring brazed to the annular step collar. The adaptor ring is welded on one end to the injector and on the other end to the metallic deposit.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:  
     
         1 . A rocket engine, comprising 
 a combustion chamber comprising an annular wall with a chamber wall outer surface and a combustion chamber axis;    an injector; and    an attachment between the combustion chamber and the injector, the attachment comprising: 
 an annular metallic deposit joined to a first region of the wall of the combustion chamber,  
 an annular transition ring structure, wherein the transition ring structure comprises: 
 an annular step collar,  
 an annular adaptor ring, and  
 a braze joint between at least a portion of the step collar and a portion of the adaptor ring.  
 
 a first joint between the adaptor ring and the metallic deposit, and  
 a second joint between the adaptor ring and the injector.  
   
     
     
         2 . The rocket engine of  claim 1 , wherein the first region of the wall of the combustion chamber is a portion of the chamber wall outer surface.  
     
     
         3 . The rocket engine of  claim 1 , wherein the second joint lies substantially perpendicular to the combustion chamber axis.  
     
     
         4 . The rocket engine of  claim 1 , wherein the step collar is made of platinum.  
     
     
         5 . The rocket engine of  claim 1 , wherein 
 the wall of the combustion chamber is made of rhenium,    the metallic deposit is made of columbium,    the first joint portion of the transition ring structure is made of columbium,    the second joint portion of the transition ring structure is made of columbium, and    the injector is made of titanium.    
     
     
         6 . The rocket engine of  claim 1 , wherein the first joint and the second joint are each weldments.  
     
     
         7 . A rocket engine, comprising 
 a combustion chamber comprising a generally cylindrical annular wall with a chamber wall outer surface, a chamber wall inner surface, and a cylindrical axis;    an injector; and    an attachment between the combustion chamber and the injector, the attachment comprising: 
 an annular metallic deposit joined to the chamber wall outer surface,  
 an annular transition ring structure including 
 an annular step collar,  
 an annular adaptor ring, and  
 a braze joint between at least a portion of the step collar and a portion of the adaptor ring.  
 
 a first weldment between a first welded portion of the adaptor ring structure and the metallic deposit, and  
 a second weldment between a second welded portion of the adaptor ring structure and the injector.  
   
     
     
         8 . The rocket engine of  claim 7 , wherein 
 the wall of the combustion chamber is made of rhenium,    the metallic deposit is made of columbium,    the first welded portion of the transition ring structure is made of columbium.    the second welded portion of the transition ring structure is made of columbium, and    the injector is made of titanium.    
     
     
         9 . A method for fabricating a rocket engine, comprising the steps of providing a combustion chamber comprising an annular wall with a chamber wall outer surface and a combustion chamber axis; 
 depositing an annular metallic deposit on a first region of the wall of the combustion chamber;    providing an attachment between the combustion chamber and the injector,    the attachment comprising an annular transition ring structure comprising an annular adaptor ring and an annular step collar;    welding the attachment to the metallic deposit;    providing an injector; and    welding the injector to the attachment.    
     
     
         10 . The method of  claim 9 , wherein the step of depositing includes the step of 
 depositing the annular metallic deposit by a technique selected from the group consisting of inertial welding, explosive cladding, chemical vapor deposition, and plasma spraying.    
     
     
         11 . The method of  claim 9 , wherein the step of depositing includes the step of 
 depositing the metallic deposit onto the chamber wall outer surface.    
     
     
         12 . The method of  claim 9 , wherein the step of welding the attachment to the metallic deposit includes the step of 
 forming a weld joint lying substantially perpendicular to the combustion chamber axis.    
     
     
         13 . The method of  claim 9  wherein the step of providing an attachment includes the steps of 
 providing an annular step collar,  
 providing an annular adaptor ring, and  
 brazing together at least a portion of the step collar and a portion of the adaptor ring.  
 
     
     
         14 . The method of  claim 9 , wherein 
 the wall of the combustion chamber is made of rhenium,    the metallic deposit is made of columbium,    the first welded portion of the transition ring structure is columbium.    the second welded portion of the transition ring structure is columbium, and the injector is titanium.