Patent ID: 8487217

Claim:
A contact tip for pulse welding with an aluminum wire by a welding gun, the contact tip comprising: an uppermost threaded end, at which the aluminum wire enters the contact tip; a lowermost exit end, from which the aluminum wire exits the contact tip; a passage larger than the aluminum wire, defined between the uppermost threaded end and the lowermost exit end, and terminating in a lower rim defining a reduced sized opening compared to other parts of the passage and generally matching the diameter of the aluminum wire, wherein the uppermost threaded end, the lowermost exit end, and the passage including the lowermost exit end and the lower rim are defined as a single piece; an insulator sleeve with a tapered upper end, located within a portion of the passage, wherein the insulator sleeve acts to eliminate contact between the aluminum wire and the passage and to define a limited contact area between the rim and the aluminum wire; and a consistent repeatable contact point defined by a location on the rim of the passage which is in contact with the aluminum wire, wherein the contact point is adjacent the exit end, and wherein having the consistent repeatable contact point on the rim of the passage allows for a consistent aluminum welding process.