Tanker to FPSO, jack-up, module integration
Conversion project software for a hull that already has systems on it, and a scope that keeps changing.
A conversion starts with an existing hull, an as-built that never quite matched reality, and a new topsides or module scope layered on top. Deskely tracks what is kept, what is removed and what is new, so the register reflects the vessel as it actually is at every stage of the conversion.
- Scope
- Legacy hull plus new topsides
- Parties
- Yard, integrator, owner, class
- Order
- Strip, reinstate, integrate
- Gate
- Class re-classification
Choose your project type
The problem
The as-built drawing says one thing, the hull says another.
A conversion inherits decades of prior repairs, class notations and modifications, few of which are fully reflected in the drawings the yard is handed at the start.
New topsides, modules and systems are being integrated onto that uncertain baseline on a schedule set before the true condition of the hull was known.
Deskely lets the register be corrected as the hull is surveyed, so the plan of record reflects reality rather than an assumption made before steel was opened up.
Setting up the register
Legacy systems, removed scope and new scope are tracked as three separate populations.
Existing systems that are retained, systems that are being removed or made redundant, and new systems being installed each need a different verification approach.
General arrangements, legacy system diagrams and new module equipment lists are parsed into one register, tagged by which population they belong to.
That separation is what stops a retained system being re-tested unnecessarily, and stops a new system being assumed proven because it sits next to something that already was.
Execution
Module integration and interface testing leave a signed record at every tie-in.
As modules land and are integrated onto the hull, interface tie-ins between new and legacy systems are recorded against both sides of the connection.
Field teams capture hook-up, hydrotest and functional records on tablet, with photos mandatory at every tie-in point.
Punch raised at an interface is visible to both the module contractor and the yard, rather than being owned by whichever side notices it first.
Re-classification and trials
Class treats a conversion as a new vessel in almost every respect that matters.
Re-classification typically requires the same rigour as a newbuild survey programme for the converted and new scope, layered on top of whatever retained class notations still apply.
Harbour and sea trials for a conversion focus on the new and modified systems, but still have to demonstrate the vessel as a whole functions as intended.
Deskely holds class survey status alongside yard and owner acceptance so a single view shows what is left before re-delivery.
Handover
The owner receives a hull with two histories that both need to survive into operations.
The as-converted dossier has to reconcile legacy documentation with new construction records, in a form the operating crew and class can both use.
Because both populations live in the same register throughout the project, the final export merges them rather than requiring a separate reconciliation exercise.
Every signature keeps a name, role and timestamp, which matters more on a conversion than almost anywhere else given the mixed provenance of the documentation.
Stability recalculation after the conversion
The hull that floated fine as a tanker has to float fine again as an FPSO, a jack-up or whatever it becomes.
Adding a full new topsides, a drilling package or accommodation modules onto an existing hull changes displacement, centre of gravity and trim in ways the original vessel's stability book never accounted for, and class will not re-issue a stability certificate on an assumption.
A second inclining experiment, or an equivalent lightweight survey, is normally required once the new scope is substantially installed, and it depends on an accurate as-converted weight record covering both what was removed from the original hull and what has been added.
Deskely tracks removed, retained and new weight against the same population tags used for commissioning, so the as-converted weight and centre of gravity submission to class is assembled from signed installation records rather than reconstructed from two separate project files at the last minute.
How it runs
From an existing hull to a re-classed, re-delivered vessel.
Conversions reward a register that can absorb correction, because the true condition of the vessel is discovered as the project proceeds.
- 01
Survey and baseline the hull
Legacy systems tagged and reconciled against as-built drawings as they are confirmed by survey.
- 02
Separate the three populations
Retained, removed and new scope tracked distinctly within one register.
- 03
Parse the new scope
Module and topsides equipment lists and diagrams drafted into the register alongside legacy tags.
- 04
Template interface records
Tie-in, hook-up and hydrotest records defined for every point where new meets legacy.
- 05
Track class re-classification
Survey status held against the same tags as yard and owner acceptance.
- 06
Export the as-converted dossier
Legacy and new-build records merged into one handover package for the owner and class.
FAQ
Questions about Vessel conversions scopes.
Keep reading
Marine and shipyard commissioning
The full sector view: hull and system registers, sea trial evidence, punch lists and redelivery certificates.
Read morePunch lists
Defects raised on board with photos, categorised by whether they block trials or redelivery.
Read moreITR records
Installation and test records defined once per equipment type and instantiated across every vessel system.
Read moreOther marine and shipyard project types: Newbuild vessel construction and trials, Drydock and repair periods, Cruise and ferry refits, Naval and defence vessel completions, LNG/LPG carriers and gas systems, OSV, PSV, CSV and walk-to-work vessels, Dual-fuel, scrubber and emissions retrofits, Shipyard facility and drydock infrastructure, Commissioning through sea trials to delivery.
