New Ross - Campbeltown
Entry Date: 09.04.2026, at 14:05:21 hrs (local)
Shaft Coupling
| PRID: | 13277 |
|---|---|
| LegID: | 368 |
| LegNo: | 110 |
| Latitude: | N052°23.27' |
| Longitude: | W006°57.48' |
| Day#: | 1700 |
| Log (Total): | 87266 nm |
Last year, we began noticing a slight vibration in the propeller shaft when running the engine above a certain RPM.
Here in the shipyard, we started investigating the cause. Our initial assumption was that the shaft might be bent, as we had previously caught a rope in the propeller. In New Ross, we had the shaft inspected and measured at a workshop. The result showed that while it was no longer perfectly straight, it was still within acceptable tolerances.
For further diagnosis, Lutz measured the shaft runout directly behind the flexible shaft coupling, a “Bullflex” type. This revealed that the deviation was outside the permissible tolerance, leading us to suspect that the coupling might be the source of the vibration.
Further research showed that the service life of our elastic shaft coupling—around 15 years—far exceeds the manufacturer’s recommendations. The manufacturer advises replacing at least the rubber elements at regular intervals.
We therefore obtained a replacement set of these rubber elements, which are now being installed. In addition, the propeller has been reworked and rebalanced in a workshop to ensure smooth and even rotation.
Whether these measures will fully eliminate the vibrations remains to be seen after reassembly and the first test runs.
