Robert Allan-designed Infield Support Vessel delivered to SeawaysVessel & ROV News // September 27, 2016
Seaways 24 is the latest addition to the RAmpage 5500-ZH class of Infield Support Vessel designed by Robert Allan Ltd. Constructed at Keppel Singmarine for owner Seaways International, the vessel was delivered in August 2016 and was designed and constructed to ABS requirements with the following Class Notation: ✠ A1, Offshore Support Vessel (AH, TOW, SUPPLY-HNLS, FFV1 + FFV 2, OSR-S1) ✠ DPS-2, ✠ AMS, ✠ ACCU, UWILD, Green Passport, ENVIRO+, SSR-GR B (300), BP125, BWT+, NBLES, CRC.
Seaways 24 is a multi-function vessel with the following capabilities:
• Tanker handling and berthing (push-pull mode)
• SBM holdback duties
• Buoy maintenance
• Anchor handling
• Floating hose handling
• Deck cargo carriage and transfers including open sea operations with installed offshore crane
• Liquid cargo transfers including methanol
• Fire-fighting with powerful Fi-Fi system with total pump capacity up to 8,200 m3/hour
• ROV support operations
• Oil recovery Standby Class 1 for recovery and storage of hydrocarbons with flashpoint below 60 °C
• Oil spill response with dispersant system and onboard Lamor oil spill collection system
• Ocean towing
• Standby and rescue operations with helicopter winch area, deck rescue zone, hospital, morgue, two fast rescue boats, and with facilities sufficient to accommodate 300 survivors.
Seaways 24 is 55m overall with a beam (moulded) of 15.00m and maximum draft of 6.05m. It tank capacities are as follows:
• Fuel oil: 590m3
• Potable water: 119m3
• Drill water: 338m3
• Water ballast: 503m3
• Methanol cargo: 99m3
• Recovered oil: 263m3
• Main engine lube oil: 20m3
• Z-drive lube oil: 6m3
• Hydraulic oil: 7m3
• Sludge tank: 11m3
• Grey water: 18m3
• Sewage holding tank: 18m3
• Oil dispersant: 25m3
• Foam: 36m3.
On trials, Seaways 24 met or exceeded all performance expectations, including a bollard pull, ahead, of 125 tonnes and bollard pull, astern, of 107 tonnes, with free running speed, ahead, in hybrid mode, of 15 knots and free running speed, ahead, in electric mode, of 7 knots.
The new vessel has 2 x 3,000kW MAK 9M25 main engines, two CAT MTA8 Z-drives each with two Power Take In (PTI) shaft connections turning CPP propellers of 3.4 m diameter in nozzles. There are also 2 x 560 kW PTI propulsion booster/economical speed/DP operation electric motors; 2 x main engine Power Take Off (PTO) gearboxes with 2 x Fi-Fi pumps and 2 x 1,200 ekW constant speed shaft alternators; and 2 X 830 ekW C32 and 1 x 350 ekW C18 ship’s service gensets.
This configuration allows the following operating modes:
• Diesel-Mechanical mode on main engines with house electrical power supplied by shaft alternators or service gensets
• Diesel-Electrical mode for economical operations on propulsion electrical motors only and with house and propulsion loads on ship’s service gensets
• Hybrid mode for maximum bollard pull and speed on main engines and on propulsion electrical motors with electrical power supplied by service gensets
• DP2 mode on main engines with house electrical power supplied by shaft alternators or service gensets
• DP1 mode on propulsion electrical motors and with house and propulsion loads on ship’s service gensets
• DP1 mode on one main engine only with house electrical power supplied by shaft alternator or service genset
• Fi-Fi 2 operation on main engines only