Stern Tube Oil Loss • Seal Leakage • Header Pressure Balance • Bearing Temperature • Reserve Endurance • Trend Monitoring
Marine Stern Tube Seal Leakage, Lubricating Oil Loss & Bearing Temperature Tool
Screen oil-lubricated stern tube condition from observed leakage, lubricant endurance, seal pressure balance and bearing temperature. Advanced mode adds separate leakage streams, bearing sensors, historical trends, pressure-balanced air-seal context, oil reserve planning and draught sensitivity.
↑
Fast condition screen with user-entered limits.No universal stern-tube leakage rate or bearing alarm temperature is assumed. Enter the vessel/OEM/class limits you actually use. The pressure comparison shown in Simple is a gravity-head screen for conventional oil-lubricated arrangements.LeakageOil loss in L/day
EnduranceDays of usable oil reserve
TemperatureBearing margin to alarm
Observed Oil Loss
L over the observation period.
hours.
L available before the entered reserve is exhausted.
days. User-entered planning target.
L/day. Replace with vessel/OEM/class criterion.
Bearing & Gravity-Head Screen
°C.
°C. Enter the vessel's actual set point.
m vertical oil head.
m seawater head at the aft seal.
System, Pressure & Reserve Basis
kg/m³ at representative condition.
kg/m³.
m.
m.
kPa. OEM/user entered; used only for air-space mode.
kPa. Conventional gravity mode only.
kPa. Conventional gravity mode only.
L.
L.
days.
days.
Seal Leakage Stream Register
Separate oil loss from seawater ingress and from controlled drain collection. Leakage limits remain vessel/OEM/class specific and are entered per row.
| Use | Seal / stream | Type | Rate L/day | Watch L/day | Critical L/day |
|---|
Bearing Temperature Register
Temperature criteria are deliberately user-entered. Compare both absolute temperature and rise above the entered local oil temperature.
| Use | Bearing | Current °C | Normal/reference °C | Oil temp °C | Watch °C | Alarm °C | Max rise above oil °C |
|---|
Historical Condition Trend
Enter normalized observations from logs. The tool trends oil consumption and aft-bearing temperature but does not diagnose the physical cause.
| Use | Elapsed day | Oil consumption L/day | Aft bearing °C | Oil temp °C | Shaft rpm | Engine load % | Shaft depth m |
|---|
Monitoring & Maintenance Checks
Engineering boundary: this tool screens trends and reserve margins. It does not diagnose seal-ring damage, certify shaft alignment, determine hydrodynamic oil-film adequacy, or replace OEM/class instructions. Air-space seals and pressure-balanced systems must be assessed against their specific control logic.