Workover Engineering
Fleet management, scheduling, NPT reduction — and the operational economics of mature-field intervention at scale.
Why this matters
In a mature giant field — Rumaila produces approximately 1.4 million barrels per day from thousands of wells — the workover programme is the single largest production-recovery lever the operator has, and it competes directly with new-drill capital for rigs, services, materials and engineering attention. Every 24 hours of unplanned non-productive time inside a workover programme is a measurable production deferment. Every redundant operation in a standard workover sequence is multiplied across hundreds of executions per year.
I have spent the last two years rebuilding how this programme is managed at one of the largest fields in the world.
Outcomes 2024 – 2025 (Rumaila Field, Basra Energy Company Limited)
| Metric | 2024 | 2025 | Change |
|---|---|---|---|
| Workovers delivered | 180 | 250 | +39% |
| Approximate rig count | ~13 | ~13 | flat |
| Incremental oil recovery attributable | — | — | +142,000 bbl/d |
| CAPEX/OPEX savings (cumulative) | — | — | ~US$100M |
| Standard rig-move duration | 3 days | 1 day | −67% |
The savings figure was driven primarily by the introduction of a 13Cr OCTG reutilisation policy — recovering and re-qualifying tubulars from completed workovers for use in subsequent operations rather than procuring new strings each time. Doing this safely, at scale, in a sour-service environment required the design of a full integrity assessment, recertification, and traceability workflow alongside the policy itself.
What I changed in the management of the programme
- Field-wide rig-move redesign. The rig-move sequence — historically 72 hours per move — was decomposed into pre-move, move and post-move workstreams with overlap. New sequence delivers under 24 hours.
- Removal of redundant operational steps. Several legacy steps in the standard workover sequence were retained “because that is how we have always done it.” Each was challenged, justified or removed.
- Equipment standardisation. Reduction in the number of distinct equipment configurations the workover fleet had to support, simplifying scheduling, contracting and crew training.
- 13Cr OCTG reutilisation policy (described above).
- Integrated programme scheduling. Workover scheduling moved from per-rig planning toward a fleet-level optimisation view — the analytical underpinning of which is now the subject of my Imperial Capstone.
Technical scope I cover
- Workover programme planning at fleet scale (10+ rigs, 200+ jobs per year)
- NPT root-cause analysis and operational re-engineering
- Tubular reutilisation policy design — qualification, traceability, sour-service compatibility
- ESP intervention strategy — workover scheduling for ESP-equipped wells, run-life analysis
- Stimulation, slickline, coiled tubing, well testing scope of work definition and tender evaluation
- Risk and well-on-paper exercises for high-complexity workovers
What I bring to a workover programme problem
I bring the conviction that the workover programme is a product of its design choices, not a fixed cost of mature-field operation. The same fleet, the same crews, the same wells can deliver substantially different outcomes depending on how the system is configured and managed. The Rumaila experience is the proof.