Marine Engineering Systems and Maintenance
Machinery, systems and planned maintenance
This domain tests the OOW's understanding of propulsion, steering, auxiliary systems, fuel and lubrication, and how to respond to alarms.
- Main and auxiliary engines need fuel, lubricating oil, cooling water and combustion air; alarm limits are not targets.
- Purifiers remove water and solids by gravity; the gravity disc and temperature affect separation.
- Steering gear has main and auxiliary/emergency arrangements; test before departure and record the test.
- Bilge, ballast and fire pumps must be lined up correctly; cross-connections can cause pollution or flooding.
- Planned maintenance systems schedule inspections; UMS alarms must be acknowledged and investigated, not silenced.
Worked example
A vessel burns 22 t/day at 16 knots. For a 3600 nm voyage, passage time = 3600 / 16 = 225 hours = 9.375 days. Fuel = 9.375 × 22 = 206.25 t. With a 15% reserve, required bunkers = 206.25 × 1.15 = 237.2 t. The OOW should compare this with usable bunker capacity, allowing for heel, trim and bad-weather margin, not just the arithmetic.
Traps
Confusing fuel mass with volume without applying density at the actual temperature. Overfilling a settling tank and causing overflow. Testing steering gear only at the berth. Resetting a high-temperature alarm without finding the cause.