Methanol/ammonia readiness, scrubbers, ballast water, shore power
Commissioning software for retrofits where a working ship has to come out proven, not just modified.
Dual-fuel conversions, methanol and ammonia readiness packages, scrubbers, ballast water treatment and shore power retrofits are executed against a fixed drydock window on a vessel that already has an operating history. Deskely holds new and existing systems in one register, so the retrofit is proven against the same rigour as a newbuild without inheriting undocumented history as an assumption.
- Scope
- Scrubber, BWTS, dual-fuel, shore power
- Constraint
- Fixed drydock window
- Interfaces
- Tie-ins to existing systems
- Gate
- Class survey and redelivery
Choose your project type
The problem
The window is fixed, and the vessel's existing systems are only partly documented.
A scrubber, ballast water treatment system, dual-fuel conversion or shore power retrofit has to be installed, tied in and proven inside a drydock window measured in weeks, on a ship whose original build records are incomplete or held by a different yard.
Tie-ins to existing piping, power distribution and control systems are where retrofit problems concentrate, and they are the hardest thing to plan for from a fixed-price scope document alone.
Deskely registers the retrofit scope and its tie-in points as their own assets from day one of the window, so the interface between new and existing systems is tracked with the same rigour as the new equipment itself.
Setting up the register
New systems and tie-in points are registered before the window opens.
Scrubber, ballast water treatment, fuel gas or methanol supply, and shore power systems are modelled as new subsystems, each with its own equipment list and record set.
Tie-in points into existing piping, electrical distribution and control systems are registered as their own assets with short, targeted record sets, because that is where the technical and schedule risk sits.
Templates are prepared ahead of the drydock, so the window opens with a register ready to receive evidence rather than one being built on the fly.
Execution
Installation, tie-in and commissioning captured against a fixed calendar.
Technicians and equipment vendors sign installation, tie-in and functional test records on tablets in the drydock, working offline where connectivity in the dock is poor and syncing on reconnect.
Punch is raised with photos and categorised by whether it blocks commissioning, sea trials or redelivery, so the yard can prioritise the items that threaten the window.
Progress rolls up per system and per tie-in, which is what lets the yard make an evidence-based go or slip decision on the window rather than a schedule-driven one.
Class survey and redelivery
Retrofit acceptance depends on a chain of new equipment and tie-in evidence.
Class survey of the new systems and their tie-ins depends on installation, functional test and — where applicable — sea trial results, each enforced as a prerequisite from records held in the register.
The dossier per retrofit system gives the owner and class the drawings, settings and test results needed to close notation and endorsement changes.
Work that does not fit the window is carried as punch with an owner and a date and stays live after redelivery, instead of disappearing into a closeout note the next yard will never see.
Gas-freeing and hot work on a live fuel system
Converting fuel tanks and piping means gas-freeing and hot-work permits sit on the critical path, not the equipment itself.
Converting existing fuel oil tanks and piping for methanol, ammonia or LNG as fuel, or tying a scrubber's exhaust duct into an existing uptake, requires the space to be gas-freed, tested and permitted for hot work before a single weld can be made, and that sequence is often the true constraint on the drydock window rather than the mechanical installation itself.
A missed gas test, an expired hot work permit, or a tank re-entry that was not re-tested after a shift change is exactly the kind of gap that halts work mid-window while the yard rechecks a space that was supposedly cleared days earlier.
Deskely records gas testing, hot work permits and re-entry checks against the specific tank or compartment, with expiry enforced so a permit that has lapsed blocks further work on that space until it is retested, rather than relying on a permit board on the quay.
How it runs
From a scoped retrofit to a vessel back on charter.
Retrofit windows are unforgiving of documentation gaps, which is why templates prepared before the vessel arrives matter more here than almost anywhere else.
- 01
Register new systems and tie-ins
Scrubber, BWTS, fuel system or shore power scope and its tie-in points modelled as assets ahead of the window.
- 02
Template the record set
Installation, tie-in and functional records prepared in advance of drydocking.
- 03
Parse retrofit drawings
Vendor drawings and interface schedules drafted into a reviewed register before work starts.
- 04
Give vendors scoped access
Equipment vendors and yard trades sign their own records while the yard sees one readiness view.
- 05
Execute inside the window
Installation, tie-in, functional test and punch capture on tablet, offline where the dock has no signal.
- 06
Close out for class and redelivery
Survey and redelivery certificates issued from signed records, with carried punch owned and dated.
FAQ
Questions about Green retrofits scopes.
Keep reading
Marine and shipyard commissioning
The full sector view: build stages, class survey evidence, sea trials and delivery documentation.
Read morePunch lists
Defects raised at the compartment or equipment with photos, categorised by whether they block trials or delivery.
Read moreWalkdowns
Pre-trial and pre-delivery inspections run as structured walks that raise punch on the spot.
Read moreOther marine and shipyard project types: Newbuild vessel construction and trials, Vessel conversions and module integration, 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, Shipyard facility and drydock infrastructure, Commissioning through sea trials to delivery.
