A federal vessel critical to maintaining navigation channels up and down the Columbia River needed refurbishing of its propulsion shafts and hubs due to corrosion damage and worn-out surfaces. Our team completed all disassembly, machining, manufacturing of shaft liners, hydro testing, spark testing, dimensional verifications and inspections, and reassembly with new hubs and components. All critical work passed certifications from ABS (American Bureau of Shipping) and the original equipment manufacturer.
Project:
- Part: Hopper dredge
- Details: 438″ shaft, 90″ dia. hub + propeller blades
- Customer: federal agency
Challenges:
- Complex disassembly & assembly.
- 2 sets of 4 shaft liners/sleeves with tapers, tight tolerances, and varying lengths.
- High-precision machining required to meet OEM specifications and ABS approvals.
Engineered Solutions:
(2) Propeller Tail Shafts & Hubs
- Complete disassembly of hubs and shafts with OEM-certified technical representative.
- Inspection of all critical fits and dimensions of tail shafts. ABS representative to witness all results.
- Comprehensive inspection of the hub components
- NDT Magnaflux inspection of both shafts.
- Machine remove 4 liners and fiberglass from each shaft.
- Manufacture 8 new liners using 316 SS material.
- Finish machine and hone ID per OEM specifications.
- Hydro testing of the liners per ABS specifications.
- Install 8 new liners on the shafts to print locations.
- Finish machine to specified sizes.
- Final dimensional and TIR checks of both shafts with ABS representative to approve all measurements.
- Blast profile of shaft surface and install new GRP coating.
- Spark test the fiberglass per ABS specifications.
- Complete reassembly of shafts with new hubs and components lubricated with required grease.
- Transportation to and from customer site.
Results:
- All technical specifications were achieved.
- Propeller tail shafts and hubs were machined and refurbished with OEM approvals and ABS (American Bureau of Shipping) certifications.
