Tuesday, July 23, 2024
Maritime Propulsion

September 13, 2023

AEGIR-Marine and UPE Conduct Major Stern Tube and Propeller Repair Job

When on route to the Gulf of Mexico area, a fully laden bulker hit a buoy off the coast of Colombia damaging the propeller blades and aft seal assembly. A close detailed inspection revealed a missing rope guard, the entire seal box being distorted and dislocated from the stern tube and all five propelled blades damaged.

Trained and certified UPE-dive technicians were mobilized, together with special habitat and relevant equipment, from AEGIR-Marine’s Panama branch.

A complete new split type seal assembly was ordered and transferred, from stock, to location. Upon arrival the UPE-team joined a local partner supplying workboat and assistance and set up the dive station on site. Findings of the detailed propeller inspection were discussed with propeller repair specialists Plug & De Boer, a repair proposal and relevant procedure submitted and approved by the attending class surveyor. Repair and replacement procedures for the seal assembly were also approved whereafter the team started making all required preparations for the foresaid repairs.

Meanwhile a new rope guard was locally fabricated for later installation.

All five propeller blades needed to be cropped and subsequently grinded in a similar way to restore the hydrodynamic balance. Damaged leading edges were ground smoothened.

During the propeller repairs the seal housing rings and seals were cut and removed one by one. Inspection of the lined showed neither damages nor excessive grooves. The damaged stern tube face and threaded holes were dressed up and a new stern flange mounted and secured.

Once the Flexdock© was in place and equipped with all safety tools and equipment, the seals were bonded and a new split type seal housing installed. After flushing and refilling the stern tube with oil, a successful pressure test and eight hours leak test were done as well as the wear down readings taken.

During fitting and welding of the new rope guard, the UPE-office submitted a report to the local surveyor and port state control who allowed the vessel to sail and continue its voyage.

Once underway at its regular sailing speed, the technical manager reported the vessel was operating normally with neither oil loss nor vibrations.