Patent ID: 7464460

Claim:
A method of metallurgically bonding a stator bar to a coupling having an interior cavity and an exterior opening thereto, the stator bar comprising a bundle of metal strands having adjacent ends, the method comprising the steps of: providing a first brazing material on a first portion of the stator bar adjacent the ends of the strands and providing a second brazing material on a second portion of the stator bar spaced apart from the first portion; assembling the stator bar with the coupling and an annular-shaped fitting so that the ends of the strands are received in the coupling through the opening thereof, the first portion of the stator bar is within the opening, and the second portion of the stator bar is outside the opening; placing a first heating means in proximity to the coupling and placing a second heating means in proximity to the annular shaped fitting; operating the first heating means to heat the coupling and the first portion therein and thereby melt the first brazing material, and operating the second heating means to heat the annular shaped fitting and the second portion therein and thereby melt the second brazing material; operating the first heating means to allow the first portion of the stator bar to cool and thereby initiate solidification of the first brazing material nearest the ends of the strands while continuing to operate the second heating means to maintain the second brazing material in a molten state, the first brazing material solidifying in a direction away from the ends of the strands and toward the second portion of the stator bar; and then operating the second heating means to allow the second portion of the stator bar to cool and thereby cause the second brazing material to solidify; wherein the first brazing material metallurgically bonds the strands to each other and the first portion of the stator bar to the coupling so as to form a fluid-tight first brazement therebetween, the second brazing material forms a second brazement that metallurgically bonds the second portion of the stator bar to the annular shaped fitting, and any surface defects in the first brazement are concentrated in a region of the first brazement farthest from the ends of the strands as a result of the directional solidification of the first brazing material.