VESSEL CONVERSION | Lilly Bordelon – Platform supplier re-enters service as IMR and light construction ship
Bordelon Marine has completed the conversion and redelivery of Lilly Bordelon as a DP2 vessel classified as an ultra-light intervention vessel (ULIV).
Rebuilt at Bordelon Marine Shipbuilders in Houma, Louisiana, the vessel is intended for subsea inspection, maintenance, repair and light construction, combining an existing platform supply vessel hull with renewed machinery and subsea working systems.
The company’s ULIV concept centres on missions that can be undertaken with two remotely operated vehicles (ROVs), a crane and a smaller, high-specification vessel. Bordelon Marine presents this arrangement as a lower-cost option for work that would otherwise employ a larger subsea vessel.
The conversion kept the existing steel hull and superstructure while replacing or adding most of the vessel’s major systems. New generators, thrusters, switchboards, variable-frequency drives, motor controls, cooling systems and pumps were among the additions, along with electronics, navigation, automation, power management, and alarm and monitoring equipment.
Wes Bordelon, President and CEO of Bordelon Marine, said that using a well-maintained hull as the base shell brought the vessel's overall cost to nearly half that of a newbuild. He also cited difficult supply chain conditions and high construction costs as reasons for undertaking the extensive rebuild instead of opting for a newbuild vessel.
The ABS-classed Lilly Bordelon has an LOA of 76.8 metres (252 feet), a beam of 16.45 metres (54 feet), and moulded depth of 5.8 metres (19 feet). The loaded draught is 4.8 metres (16 feet) and the deadweight is 2,930.
The principal lifting equipment is an SMST active heave-compensated crane with a 60-tonne static payload rating and a fully redundant power source.
The clear main working deck covers 511.71 square metres (5,510 square feet) and measures 32.92 by 15.54 metres (108 by 50.98 feet). Its specified strength is 5,273 kg/m². There is also a separate launch and recovery system (LARS) deck.
Full range of ROV handling gear
The mezzanine arrangement supports two work-class ROVs and includes an integrated ROV control room. The LARS deck meanwhile carries the same specified load rating as the main deck.
Deck services include 480V three-phase electrical supplies at three locations, with 380A specified, and compressed air at 95 psi. The conversion also added two independent, through-hull USBL deployment systems, complementing the vessel’s subsea working equipment and positioning references.
Propulsion arrangement suitable for dynamic positioning as well as transits
The diesel-electric plant has a total output of 7,050 kW from six generators. Two Cummins QSK60 EPA Tier III units each provide 2,250 kW, one QSK38 Tier II unit provides 975 kW, and three QSK19 Tier III units each provide 525 kW. A separate Cummins 6TA8 emergency generator is rated at 201 kW.
Propulsion and manoeuvring are provided by two Steerprop SP20 azimuthing thrusters and two Berg bow thrusters.
A DP2 multi-function integrated bridge system incorporates independent systems. Position references include two CNAV 3050 DGPS receivers with independent tracking and Kongsberg CyScan and RadaScan equipment.
The integrated alarm, monitoring and control installation tracks 1,000 input/output points through independent consoles. Power management and load shedding extend across all power sources.
Bordelon Marine said the vessel has a maximum speed of 12 knots, a service speed of 10 knots, and an economical speed of 8.5 knots. Its stated consumption during dynamic positioning is 12 to 30 gallons (45 to 110 litres) per hour.
The total diesel fuel capacity is 540,000 litres (140,000 gallons).
Expanded and modernised crew facilities
The rebuild also renewed heating, ventilation and air conditioning, joinery, flooring, ceiling work and lighting. The work covered the galley and cold store facilities, offices, staterooms, a lounge, an auxiliary mess and a gym. The tanks, hull, and superstructure were recoated. The new staterooms meanwhile have individual heads and climate controls.
Accommodation increased to 63 berths across 22 staterooms, with 25 heads and showers. Project spaces include an offshore manager’s office, a conference room, an ROV online room, project and client offices, a survey area, a shift supervisor desk, and a dedicated power distribution and instrument room.
Two laundry facilities contain eight stacks, and the hospital has capacity for three people.
The D-value helideck is certified by the US Coast Guard and ABS to CAP 437 requirements and can support an AW189 helicopter.
The safety equipment includes six 25-person life rafts, a Schat Harding self-propelled fast rescue craft, and water and foam firefighting monitors.
