Ashoke K Mukherjee

Address:

13067 Hatherton Cir, Orlando, FL 32832

VIN:

4T1BE46K87U680108

Make:

TOYOTA

Model:

CAMRY

Year:

2007

US Patent:

52014550, Apr 13, 1993

Filed:

Aug 21, 1992

Appl. No.:

7/933168

Inventors:

Samuel D. Reynolds - Oviedo FL
Ashoke K. Mukherjee - Orlando FL

Assignee:

Westinghouse Electric Corp. - Pittsburgh PA

International Classification:

B23P 600

US Classification:

228119

Abstract:

A method for metallurgical enhancement of a failed bolt hole, or stud attachment, providing for replacement of service induced failed material from the female threaded area of the bolt hole. A method in accordance with the present invention is particularly suited for power plant equipment, such as a steam turbine. Failed material from the female threaded area is removed and filler metal is arc welded to the exposed base metal of the hole using a mechanized gas tungsten arc weld device employing a continuous spiral weld bead. Proper selection of the filler metal, considering the base metal to which it is applied and, moreover, the type of failure which the base metal of the hole has been experiencing, provides for improved structural integrity of the mechanical joint and increased service life of the associated steam turbine apparatus. Weld tempering of the filler metal reduces undesirable weakening of the weld metal in the heat affected zone, thus providing further metallurgical enhancement of the failed bolt hole.