Composite to metal joint and method for forming same

Abstract

A composite pipe to metal fitting joint including a shell formed with a conical cavity receiving a tapered end of a composite tube for bonded therein. The method includes selecting the metal fitting of a composite tube and bonding together.

We claim: 
     
         1 . A composite to metal tube joint comprising:
 a metal fitting including a distally projecting sleeve formed with a radially inwardly facing, distally and radially outwardly angled fitting bonding surface of a predetermined configuration;   a composite tube formed on one end with a bonding ring having a radially outwardly facing ring bonding surface tapering distally and radially outwardly to compliment the predetermined configuration; and   a bond bonding the bonding surfaces together.   
     
     
         2 . The composite tube joint of  claim 1  wherein:
 the fitting bonding surface is continuous and smooth. 
 
     
     
         3 . The composite tube joint of  claim 1  wherein:
 the fitting bonding surface is conical. 
 
     
     
         4 . The composite tube joint of  claim 1  wherein:
 the fitting and ring bonding surfaces are conical. 
 
     
     
         5 . The composite tube joint of  claim 1  wherein:
 the metal fitting includes an annular proximal facing shoulder; and 
 the composite tube includes an annular tube end abutted against the shoulder. 
 
     
     
         6 . A composite metal to tube joint comprising:
 a composite tube formed with a bonding ring having a conical radially outwardly facing bonding surface of a selected configuration;   a metal fitting including wall defining a cavity formed to compliment the selected configuration and receiving the bonding ring to form an interface; and   a bond in the interface.   
     
     
         7 . The composite tube joint of  claim 6  wherein:
 the bonding surface is continuous and smooth. 
 
     
     
         8 . The composite tube joint of  claim 6  wherein:
 the bonding surface is in the shape of a cone. 
 
     
     
         9 . The composite tube joint of  claim 6  wherein:
 the interface is conical. 
 
     
     
         10 . The composite tube joint of  claim 6  wherein:
 the metal fitting includes an annular proximal facing shoulder; and 
 the composite tube includes an annular tube end abutted against the shoulder 
 
     
     
         11 . A method of making a composite tube joint including:
 selecting a metal fitting including a distally projecting annular sleeve formed with a radially inwardly facing distally and radially outwardly angled fitting bonding surface of a predetermined configuration;   selecting composite tube formed on one end with a bonding ring having a radially outwardly facing ring bonding surface tapering distally and radially outwardly to compliment the predetermined configuration;   inserting the bonding ring in the sleeve; and   bonding the bonding surfaces together.   
     
     
         12 . The composite tube joint of  claim 11  that includes:
 selecting the metal fitting and composite tube with bonding surfaces is continuous and smooth. 
 
     
     
         13 . The composite tube joint of  claim 11  that includes:
 selecting the metal fitting with the fitting bonding surface conical. 
 
     
     
         14 . The composite tube joint of  claim 11  that includes:
 selecting the metal fitting and composite tube with bonding surfaces conical. 
 
     
     
         15 . The composite tube joint of  claim 11  that includes:
 selecting the metal fitting with an annular proximal facing shoulder; 
 selecting the composite tube with an annular tube end; and 
 abutting the tube end against the shoulder.