An LNG vessel was recently found to be leaking oil at a terminal due to a deformed and broken bottom cover gasket. Cause of the defect was over-tightening of the bottom cover securing bolts during factory assembly. A “save-all” arrangement prevented a spill.
The incident was covered in a recent Mars Report (anonymised maritime incident reports collected by The Nautical Institute). A summary of what happened:
An LNG vessel arrived at a terminal for discharge. During the mooring operations, oil leakage was observed from the bottom cover of the hydraulic motor of one of the forward mooring winches. The leakage was immediately reported to the bridge. The leaked hydraulic oil (about twenty litres) was contained by the winch’s “save-all” arrangement.
Lessons Learned
- Proper torque tightening should be verified periodically on equipment.
- Save-all arrangements are a great defence against overboard oil release. Ensure they are clean, dry and free of any objects that will reduce their capacity.
Mars Reports
This accident was covered in the Mars Reports, originally published as Mars 201966, that are part of Report Number 324. A selection of this Report has also been published in SWZ|Maritime’s November issue. The Mars Reports are also published on SWZ|Maritime’s website to help prevent maritime accidents.
More reports are needed to keep the scheme interesting and informative. All reports are read only by the Mars coordinator and are treated in the strictest confidence. To submit a report, please use the Mars report form.
