Offshore Hull Cleaning Campaign: Franmarine Delivers in International Waters

Franmarine has successfully completed a major offshore hull cleaning campaign aboard an ultra-deepwater drilling ship operating in international waters — one of the most technically demanding environments in which robotic hull maintenance can be conducted.

Operating on Dynamic Positioning

A defining requirement of this project was that the drillship remained on dynamic positioning (DP) throughout the entire campaign. DP enables precise station-keeping without anchoring, protecting subsea infrastructure and ensuring vessel readiness is never compromised. For the hull cleaning team, this meant operating in open water without the benefit of a fixed or sheltered berth – every element of the operation had to account for vessel movement, current, and swell in real time.

Conditions That Tested the Team

The environmental and fouling conditions encountered during this campaign were severe:

• Current: 2–4 knots throughout the majority of the campaign
• Swell: 2–4 metres
• Duration: 24/7 operations over a 3-week campaign
• Fouling rating: FR30 to FR100, including dense calcareous growth and barnacles up to approximately 200 mm in diameter
• Logistics: Complex international and offshore coordination across the full campaign period

Maintaining 24-hour operational continuity under these conditions – managing shift-to-shift handovers, equipment performance, and cleaning quality simultaneously – required both a high level of operational discipline and equipment that could keep up.

Scope Delivered

Despite the conditions, the project team delivered the full scope:

• Flat hull plating cleaned across all treated areas
• Above-waterline cleaning completed where practicable
• End condition achieved: FR0 across all treated surfaces
• Digitally enabled technical reporting to Class and regulatory specification, delivered through the MarineStream platform

An FR0 end condition on surfaces that entered the campaign at FR100, with dense hard growth, reflects genuine cleaning performance, not just a pass-and-go operation.

From the Team

Marc Green, Franmarine ROV Manager, reflected on the delivery:

“Working offshore on a drillship in these conditions tested both the team and equipment. With 2–4 knots of current most days and 2–4 metres of swell, combined with dense calcareous fouling, the operating environment was demanding. The outcome was a testament to the operational knowledge and problem-solving expertise of the team, coupled with the mag crawler’s stability, control, and capacity to keep performing consistently despite the conditions. Furthermore, the performance in-field was reinforced by strong support from our Australian management team, the client, and the manufacturer throughout the campaign – overall, it was an exceptional team effort that I am proud of.”

What This Demonstrates

This campaign is a clear demonstration of Franmarine’s capability to deliver DP-compatible, round-the-clock offshore inspection, maintenance and repair (IMR) interventions. Robotic magnetic crawler technology enables consistent performance where environmental forces, fatigue risk, and safety constraints make traditional commercial diving cleaning impractical or impossible.

The combination of engineering control, magnetic stability, and digital reporting through MarineStream positions Franmarine as a capable partner for clients with demanding offshore maintenance requirements – supporting operational readiness, fuel efficiency, and hull integrity where it matters most.

For more information on Franmarine’s offshore hull cleaning capabilities, or to discuss your vessel’s requirements, get in touch with the team.