Executive summary
Lube oil is the cheapest insurance policy on a vessel. A single sample tells a Technical Superintendent whether a bearing is wearing, whether seawater is leaking into the cooler, whether fuel is diluting the crankcase, whether the FW generator membrane is failing. Lube oil also moves through tanks: ROB management, bunker planning, and the cost of running out at sea — all driven by the same numbers. The Lube Oil Surveillance pipeline tracks four parallel streams:- Shore analysis results — wear metals, additives, contaminants, TBN, viscosity from the lab
- Sampling compliance — per-machinery sample dates, frequency, next-due, overdue flags
- Tank ROB & bunker planning — distribution by tank, capacity, recommended intake to reach 85%
- Daily consumption — AE crankcase oil from the consumption form, compared against maker limits
Architecture
Stage 1 — Data collection
Where the data comes from
The lube-oil pipeline pulls data from three independent surfaces and reconciles them:
Lab analysis is sourced from any of the major marine lube-oil laboratories the vessel uses:
Most labs send results by email; the pipeline parses the lab report (PDF or structured email body) and normalises into the same shape regardless of source.
For each lubricated equipment (main engine system oil, cylinder oil, AE crankcase, hydraulics, gearboxes), the collector captures:
Lab analysis
Sampling schedule
Per machinery: sample frequency, last sample date, next-due date, due-status (Overdue / Due / In Order), test lab, report links, line items per past sample.Tank ROB
Per tank: grade, tank name, current ROB (litres), 100% capacity, 85% capacity, ullage, calculated bunker intake to reach 85%.Daily consumption
Per AE per day from the consumption form: crankcase oil consumption (L/day), running hours, comparison vs maker limit.Stage 2 — Analysis
2.1 Wear-metal trends
For each metal the analyzer computes period-over-period change: A step jump where is treated as a discrete event, not noise — bearing wear, ring failure, contamination ingress are all step events; gradual rise across three samples is a different signature.2.2 Contamination flags
Each contaminant maps to a specific equipment risk:2.3 TBN reserve and viscosity drift
TBN reserve is tracked against the fresh-oil baseline: Tier:- — Healthy
- — Trend down, monitor
- — Oil change discussion
- — Overdue
2.4 Sampling compliance
Per machinery, the analyzer enforces the sample frequency: Status mapping:
The per-machinery view assembles the same shape across every lubricated component. Condensed:
2.5 Tank distribution & bunker planning
For each tank, the analyzer computes how much to bunker to reach 85% capacity (the safe operating headroom): where is the 100% tank capacity and is the current ROB. Negative intake means the tank is already above 85% — flag for ullage check. The aggregate view collapses intake across all tanks per grade, then surfaces the recommended order quantity per grade for the next bunker call.2.6 Daily consumption vs maker limit
For AE crankcase oil from the consumption form: Compared against the maker’s specification limit: Sustained variance above 20% signals piston-ring blow-by or excessive cylinder feed-rate — both are top-end overhaul candidates.2.7 Equipment-pattern correlation
The analyzer cross-references LO trends with equipment running hours and recent overhauls — wear after a recent overhaul is break-in; sustained wear well into a service interval is accelerated degradation. Cylinder cylinder uniformity findings on the main engine often confirm or rule out a wear-metal trend on the same engine.Worked example
Vessel:MV POSUN, MAN 6S60ME-C main engine.
After a refresh:
LO tank ROB:
Verdict: HIGH — ME system oil iron step-jump combined with sample overdue on AE3 means the analyzer is missing data on one engine while another shows accelerating wear.
The pipeline:
- Tags the run with
escalation_required: true - Updates the case to
awaiting-tsi-review, priority CRITICAL - Sends an A2A message to the TSI inbox with the wear-metal evidence and the bunker-planning view
- Investigate ME system oil iron step-jump — pull bearing inspection at next port.
- Schedule AE3 LO sample within 48h — restore sampling cadence.
- Plan ME cylinder oil change at next port — TBN reserve below 50%.
- Bunker request: ME system 4,350 L, cylinder 3,050 L; AE crankcase already at 85%.
Output deliverables
- Executive summary — overall LO posture, headline flags
- Per-equipment lab table — wear metals, additives, contaminants, TBN, viscosity
- Wear-metal trend chart — period-on-period rate of change per metal
- Contamination findings — per equipment with likely cause
- TBN & viscosity status — reserve %, drift direction
- Sampling compliance — per machinery, next due, overdue list, link to lab report
- Tank ROB & bunker plan — per grade, recommended intake to reach 85%
- Daily consumption — AE crankcase oil vs maker limit
- Equipment correlation — recent overhauls, running hours, ME / AE cross-reference
- Recommendations — prioritised by impact, with timeline
- Escalation decision — auto-routed to TSI when triggered
Escalation triggers
Why script-driven
Wear-metal rate maths, TBN-reserve calculation, sampling-frequency arithmetic, and bunker-intake formula all live in deterministic Python. The reviewer interprets the result; verdicts are reproducible. A wear-metal trend that flips from “monitor” to “escalate” between two samples is a real change in the data, not a model decision.Sample compliance and lab analysis matter together. A vessel sampling on time but ignoring the trend is not better than a vessel skipping samples — both end with the same engine overhaul. The pipeline reports both streams in the same review so the TSI sees them together.
References
Templates: lube-oil-analysis
Lube-oil-analysis suite — shore-analysis status and tank distribution & bunker planning.
Templates: performance-analysis
Performance-analysis suite — AE LO consumption, shore-analysis data, and shore-analysis scheduling.
Related: ME performance
Wear metals confirm or rule out cylinder findings on the main engine.
Related: AE performance
Crankcase oil consumption is the top-end overhaul leading indicator for AEs.