Roger W Sholle

US Patent:

41172973, Sep 26, 1978

Filed:

Nov 22, 1976

Appl. No.:

5/743865

Inventors:

Roger W. Sholle - Lorain OH

Assignee:

TRW Inc. - Cleveland OH

International Classification:

B23K 932

US Classification:

219 98

Abstract:

A ferrule for use in end welding a stud to a workpiece and a method of welding with the ferrule are set forth. In end welding a stud to a workpiece, the stud is first placed with an end against the workpiece and is then retracted as a low current pilot arc is formed between the stud and the workpiece. A main high current weld arc is then superimposed between the stud and the workpiece. This arc causes portions of the stud and the workpiece to be molten and the stud is then plunged forward to engage the workpiece. The molten portions join and solidify to securely weld the stud to the workpiece when they return to full contact. Some of the molten metal tends to flow outwardly as the stud strikes the workpiece to establish a fillet between the stud and the workpiece. This fillet under normal conditions is substantially uniformly formed with the aid of a ferrule located around the end of the stud to help control the flow of molten metal and to reduce splatter of the metal. Under some welding applications, the flow of molten metal is not uniform around the stud but may be excessive on one side and on the opposite side, there may be a cavity or washout where the fillet would otherwise be, between the welded stud and the workpiece.