Marine Works Fleets: Maintaining Plant That Never Runs the Same Way
France currently has four offshore wind farms in operation, for 1,474 megawatts installed, five more under construction and fourteen at project stage, against a national target of 45 gigawatts by 2050. Behind those figures sits sustained demand for marine works fleets: barges, tugs, pontoons, cable-lay plant and support craft.
Such fleets have a characteristic that conventional maintenance tools handle badly: nothing in them runs at the same rate. A tug strings three weeks of cable-lay together, then lies at moorings for a month. A barge works twelve hours a day through a contract, then waits for the next one. Scheduling a job every six months under those conditions means choosing between waste and breakdown.
The essentials
Use of marine works plant is irregular by nature, so calendar scheduling is structurally wrong for it.
A works fleet mixes registered vessels with plant that carries no registration but needs the same upkeep.
Traceability serves two audiences: the client during the contract, the insurer after the casualty.
On a remote site, a tool that needs a network connection to log a job will not be used.
A mixed fleet on an irregular cycle
The first obstacle lies in the make-up of the plant itself. A marine works contractor rarely operates comparable units: a thirty-metre tug, two dumb barges, a crane pontoon, a few workboats, and a collection of shipboard equipment each with its own periodicity. Bringing them into one maintenance plan means reasoning by item of equipment rather than by vessel.
The second lies in the rhythm. A contract mobilises the fleet intensively, then releases it; the gap before the next award may be days or months. A main engine counter can gain 300 hours in three weeks, then nothing until spring. No calendar models that correctly.
Running hours rather than dates
Tying each job to an hour counter settles the problem at source. The oil change falls due at 250 running hours, whether those hours were accumulated in three weeks or eight months. A winch inspection follows the cycles actually worked. Statutory items stay on fixed dates, and the two logics coexist within the same plan.
The operational benefit goes beyond technical accuracy. A plan built on real use allows anticipation: at the end of a contract you know which machines are approaching a due point and which can go straight onto the next award. That is the difference between scheduling downtime and suffering it. The principle sits at the heart of what is meant by a marine CMMS.
Unregistered plant counts too
A frequent mistake is to track only what carries a registration number. Yet half the downtime on a site comes from elsewhere: a generator, a pump, a deck crane, a compressor. Such equipment has no regulatory standing of its own, but its failure halts production as surely as a propulsion breakdown.
Bringing it into the same plan as the main engines, with its own counter and history, costs little and changes much. It simply requires a tool willing to treat an asset without attaching it to a hull.
Records for the client, and for the insurer
Marine works differ from transport in one respect: the client is present. A principal paying day rates for a barge asks questions about stoppages, and a delay attributed to a breakdown is argued with evidence. Having an asset's history to hand, with dates, names and parts consumed, changes the nature of that conversation.
The same file serves later, in a less friendly setting. After a casualty, the surveyor seeks to establish whether maintenance had been carried out. A documented answer counts for more than a statement of good faith, and it is usually what is missing when the record was kept in a notebook aboard the unit that sank.
What a site team will actually do
Which leaves the question that settles everything: will the crew fill the tool in? On a site, the answer rests on two conditions. Logging must take a few taps on a phone, and it must work without coverage, since works areas rarely have any. An arrangement that requires going back aboard, opening a laptop and finding a shared file does not survive its first week.
The rest follows: if readings go in as work happens, the plan updates itself, alerts fire at the right moment, and the operations manager stops spending Friday afternoons on the telephone establishing where the machines stand. The marine works page sets out how this works, and the engine log module shows how counters are kept.
With fourteen offshore wind farms still at project stage in France alone and a 45 GW national target, order books for works fleets are unlikely to thin out. The question is which operators will be able to account for the condition of their plant as quickly as they are asked to.
Source: status of offshore wind in France, Révolution Énergétique. Illustrative photograph.
