LASER WELDING HEAD FOR SLEEVE-TO-TUBE WELDING
 Inventors: Phillip J. Hawkins; William H.
Kasner, both of Penn Hills
Township, Alleghney County;
Richard A. Miller, North
Huntingdon, all of Pa.
 Assignee: Westinghouse Electric Corp.,
 Appl. No.: 821,674
 Filed: Jan. 23, 1986
 Int. CI* B23K 26/00
 U.S. CI 219/121 LC; 219/121 LQ;
 Field of Search 219/121 LC, 121 LD,
219/121 LQ, 121 LR
 References Cited
FOREIGN PATENT DOCUMENTS
0224092 12/1983 Japan 219/121 LU
0107785 6/1984 Japan 219/121 LQ
Primary Examiner—C. L. Albritton
Attorney, Agent, or Firm—D. M. Satina
A laser welding head for welding a sleeve within a tube by fusing the interface between the sleeve and tube with a laser beam. The laser welding head has a cylindrical housing adapted to be inserted inside of the sleeve, a focusing lens for focusing a laser beam transmitted through the housing, and a welding mirror for directing the focused beam out of the housing and into contact with the sleeve. The welding mirror is maintained a predetermined distance from the inside surface of the sleeve and a motor and drive assembly are used to rotate the welding head within the sleeve. Shield gas is supplied to the welding head and passes about the periphery of the focusing lens for cooling the focusing lens and the welding mirror before being discharged into contact with the weld area. A recessed aperture is provided within the discharge outlet to prevent molten material from the weld site from splattering into the housing and onto the mirror or lens. Multiple pass welds are preferred for attaching each end of the sleeve to the tube with the preferred weld paths being either multiple discrete weld paths or continuous overlapping helical weld paths at each end of the sleeve.
24 Claims, 19 Drawing Figures