Little Goose Unit 3 Hub Shaft Repair

The project involves sealing a known oil leak on a Kaplan turbine shaft hub, allowing Unit 3 to resume normal Kaplan operations. Little Goose Main Unit 3’s Kaplan turbine runner was forced out of service when the turbine was found to be leaking oil. The main scope of work for this contract addresses the leak found at the turbine shaft to hub flange. The o-ring between the top of the Kaplan hub and the shaft lower flange has failed at this location.

The work detailed will contain the runner leakage and route the leaked oil back to the static oil head. Instead of replacing the failed o-ring (requiring unit disassembly), this job seeks to contain leakage by sealing the outer diameter of the shaft flange where it meets the hub. It will also include welded caps for each coupling bolt, and piping at the shaft jacking bolts to contain leaking within the flange face and routing it back to the static oil head. The work will be completed with the unit partially disassembled (performed by government personnel) and confined to the turbine pit with limited egress.