ICON Engineering was engaged by a large independent West African energy company to conduct a Concept and Transport and Installation (T&I) Optimisation Review of a conductor support platform design for its offshore wellhead development. The platform forms an integral part of the client’s development programme for a large offshore oil field, and the design was proposed to be replicated across the field — meaning any inefficiency in the concept would be repeated at every location it was rolled out to.
Why the Original Conductor Support Platform Design Carried Cost and Schedule Risk
The third-party original design was based around the concept of a conductor support platform (CSP), in which the wellhead structure is supported by, and installed around, the conductors themselves rather than a single integrated jacket. A CSP design typically comprises multiple separate components — substructure sections, topsides modules and ancillary structures — each of which has to be lifted and installed individually by the jack-up drill rig in critical path time.
Given the high day rate of a drilling spread, a multiple-piece CSP design carries both significant schedule and cost disadvantages relative to a conventional single-piece substructure and single-piece topsides. Every extra lift, alignment and connection adds hours to the rig’s critical path, and in a jack-up-supported installation (see the SLB Energy Glossary definition of a jackup for background on how these rigs operate), that time is charged directly against the project economics.
Having previously experienced the schedule and safety drawbacks of CSP installation firsthand, the client asked ICON to:
- review the existing design;
- improve safety for construction personnel;
- reduce overall technical risk; and
- develop new cost- and schedule-effective rig installation methods.
ICON’s Conductor Support Platform Optimisation Approach
ICON worked closely with the client’s engineering team to develop recommendations for modifying the existing substructure and topsides design without triggering a full design restart. The recommended modifications included:
- a reduced number of substructure and topsides components;
- no diving or major construction work below the water surface;
- a single-piece substructure design; and
- simplification of the topsides structures.
This approach reflects ICON’s broader transport and installation engineering philosophy: design decisions made early in concept and FEED have an outsized effect on offshore execution risk, cost and duration, so they’re worth revisiting even late in a project. That held true here — even though the platform was already in fabrication at the yard when ICON’s review began, ICON and the client were still able to significantly improve the installation sequence, duration, cost and risk profile within those constraints.
Platform Data
| Platform Data | |
|---|---|
| Water depth | 28m |
| Lower substructure weight | 180mT |
| Topsides weight | 400mT |
Outcomes for the Client’s Field Development Programme
For future platforms in the field, the client is now able to implement all of ICON’s recommended enhancements to the conductor support platform design from the concept stage, rather than retrofitting them once fabrication is underway. That gives the client a repeatable, lower-risk installation methodology it can apply across the remaining wellhead platforms in its development programme, rather than re-solving the same CSP installation challenges at every location.
The project sits alongside ICON’s wider track record in rig-installed wellhead platforms, where the same discipline — reducing offshore scope, simplifying interfaces and shortening rig critical path time — is applied across substructure, topsides and installation engineering. It’s a good example of how a targeted optimisation review, run well after concept select, can still materially change a project’s cost, schedule and safety outcomes.
More broadly, the review illustrates a pattern ICON sees across field development work in West Africa and elsewhere: a conductor support platform design that looks fixed once fabrication has started often still has real optimisation headroom, provided the review focuses on installation sequencing and interface simplification rather than a ground-up redesign. Independent energy companies planning multi-platform CSP campaigns can apply the same review approach before committing later platforms in the campaign to fabrication, capturing the cost and schedule benefit across the whole field rather than a single asset.
