Kaplan Turbine Bearing Housing
 Problem: The main guide bearing on this small Kaplan turbine loosened while in service causing vibration and bearing failure. The bearing housing sits underground in a very confined working area. Since there is little room to work, a large torque wrench can not be used to tighten to the 417 ft-lbs of torque required. A winch was used to tighten the standard hex bolts and the torque achieved was questionable.
Superbolt Solution: (8) SB8-125-8x4/w Torquebolts® were utilized. The final jackbolt torque to achieve a preload of 48,600 lbs was 27 ft-lbs. Small 3/8" drive torque wrenches were easy to manipulate in the tight workspace. Total time for the installation was about an hour.
 SB8 Torquebolt® series used.
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