Dual wire welding system and method

Abstract

A system and method of welding is provided where at least two welding electrodes are provided to and passed through a single orifice on a single contact tip and a welding waveform is provided to the electrodes through the contact tip to weld simultaneously with both electrodes.

What is claimed is: 
     
         1 . An arc welding system, comprising:
 a welding gun including a contact tip having a channel and an exit orifice;   an arc welding power supply which provides an arc welding waveform to at least two arc welding consumable electrodes having a circular cross-section via said contact tip; and   a wire feeding mechanism which provides said at least two arc welding consumable electrodes from respective electrode sources to said channel in said contact tip, where said arc welding electrodes pass through said channel in a longitudinal orientation without intertwining or twisting with each other and exit said contact tip through said exit orifice.   
     
     
         2 . The welding system of  claim 1 , wherein said channel is angled. 
     
     
         3 . The welding system of  claim 1 , wherein said orifice has either an elliptical or oval shape. 
     
     
         4 . The welding system of  claim 1 , wherein said channel has a cross-sectional shape at at least one point along its length which is different from the cross-sectional shape of said orifice. 
     
     
         5 . The welding system of  claim 1 , wherein said channel has a circular cross-section at at least one point along its length. 
     
     
         6 . The welding system of  claim 1 , wherein said contact tip is rotatable so as to change the orientation of said at least two electrodes relative to a weld bead. 
     
     
         7 . The welding system of  claim 1 , wherein said at least two electrodes have a different diameter from each other. 
     
     
         8 . The welding system of  claim 1 , wherein said at least two electrodes have a different composition. 
     
     
         9 . The welding system of  claim 1 , wherein said welding waveform provides a welding current sufficient to weld with a single electrode having a cross-sectional area substantially the same as the total cross-sectional area of said at least two electrodes. 
     
     
       10. An arc welding system, comprising:
 a welding torch;   a contact tip;   a channel for receiving two arc welding consumable electrodes from respective electrode sources, wherein said arc welding electrodes pass through said torch in a longitudinal orientation without intertwining or twisting with each other and exit said torch; and   a single wire feeder which drives said two arc welding consumable electrodes from said respective electrode sources to said channel;   wherein said two arc welding consumable electrodes are in contact with each other within said channel;   wherein said wire feeder comprises a single pair of feed rollers configured to drive said two arc welding consumable electrodes to said channel, said feed rollers being designed for a single wire feeding operation; and   wherein an arc welding power supply provides a single arc welding waveform through said contact tip for consuming said two arc welding consumable electrodes to generate one arc and one weld puddle from said two arc welding electrodes.    
     
     
       11. An arc welding system, comprising:
 a contact tip, wherein said contact tip aligns two arc welding electrodes from respective electrode sources to pass through said contact tip in a longitudinal orientation without intertwining or twisting with each other and exit said contact tip, wherein said two arc welding electrodes are in contact with each other as the two arc welding electrodes pass through said contact tip, and wherein an arc welding power supply provides an arc welding waveform through said contact tip to consume said two arc welding consumable electrodes to generate one arc and one weld puddle from said two arc welding electrodes; and   a single wire feeder which drives said two arc welding consumable electrodes from said respective electrode sources to said contact tip;   wherein said wire feeder comprises a single pair of feed rollers configured to drive said two arc welding electrodes to said contact tip, each roller having a single operable groove for driving said electrodes.    
     
     
       12. The welding system of  claim 10 , further comprising a liner disposed between said welding torch and said wire feeder, wherein said wire feeder drives said two electrodes from respective electrode sources through said liner to said welding torch.  
     
     
       13. The welding system of  claim 12 , wherein said two electrodes pass through said liner in a longitudinal orientation without intertwining or twisting with each other to deliver said two electrodes to said welding torch.  
     
     
       14. The welding system of  claim 11 , further comprising:
 a welding torch and a liner disposed between said welding torch and said wire feeder, wherein the welding torch includes the contact tip, and wherein said wire feeder drives said two electrodes from respective electrode sources through said liner to said welding torch.    
     
     
       15. The welding system of  claim 14 , wherein said two electrodes pass through said liner in a longitudinal orientation without intertwining or twisting with each other to deliver said two electrodes to said welding torch.  
     
     
       16. The welding system of  claim 10 , wherein said contact tip comprises a single orifice.  
     
     
       17. The welding system of  claim 16 , wherein said two electrodes exit said contact tip through said orifice.  
     
     
       18. The welding system of  claim 11 , wherein said contact tip comprises a single orifice.  
     
     
       19. The welding system of  claim 18 , wherein said two electrodes exit said contact tip through said orifice.  
     
     
       20. The welding system of  claim 10 , wherein a single arc welding power supply provides the arc welding waveform.  
     
     
       21. The welding system of  claim 11 , wherein a single arc welding power supply provides the arc welding waveform.  
     
     
       22. The welding system of  claim 16 , wherein said orifice has either an elliptical or oval shape.  
     
     
       23. The welding system of  claim 18 , wherein said orifice has either an elliptical or an oval shape.  
     
     
       24. The arc welding system of  claim 10 , wherein each of said arc welding consumable electrodes has a diameter of 0.030 inches.  
     
     
       25. The arc welding system of  claim 11 , wherein each of said arc welding electrodes has a diameter of 0.030 inches.