From the "News & Standard," Coulee City, WA
August, 9, 1973
Unloaded last week at Odair by Weilhelm Trucking, Portland---One section of main generator shaft---The largest shaft ever built, this section is 18 feet long, weighs 240,000 pounds, has an inside measurement of 8 feet and inside walls 8 inches thick. It bolts together with two other sections, using 26 bolts weighing 500 lbs each and 26 nuts weighing 150 lbs each. An ingenious method had been adopted for tightening the nuts. Each bolt and nut is preheated before being placed in position, the nut is then threaded and turned a pre-determined number of turns. The bolt is then allowed to cool drawing up the nut so tight that the only way it can ever be loosened is to reverse the preheating process.
The hollow shaft is built of special steel which allows the shaft to flex. According to Mr. Reekie, West Coast General Manager of Westinghouse Electric Corp., the water wheel attaches to the bottom of the generator shaft and when the water from the 40 ft water tubes hits the wheel there is so much force that the lower end of the shaft twists and begins turning before the top end starts. The flexible feature then allows the top to catch up with the bottom in revolutions.