Fortescue Metals Group needed stable, higher-powered support tugs as it increases bulk exports in Western Australia
Naval architects at Robert Allan modified an escort tug design for a new fleet at an Australian bulk export terminal.
Eight new Rotortugs were built in Asia to provide additional manoeuvring support at an integrated mining and export centre in Port Hedland, Western Australia.
Fortescue Metals Group (FMG) subsidiary, Pilbara Marine, selected Robert Allan’s ART 85-32W Rotortugs to support increased exports from the Pilbara region.
FMG chief executive Elizabeth Gaines said these new tugs were essential for its expanding mining operations in the region.
“Fortescue operates the most efficient bulk port operation in Australia and the towage fleet represents the final element in our supply chain,” she said. “With our innovative new tug fleet, we are able to provide safe and reliable towage services and additional towage capacity for all Port Hedland users.
“The tug fleet and new facilities will maximise the efficiencies of our operation and provide long-term sustainable towage services crucial to meeting the demands of our customers,” Ms Gaines said.
Six of the new Rotortugs were constructed by Damen Shipyards at its Song Cam shipyard in Vietnam and two more were built by Cheoy Lee Shipyards of Hong Kong.
All eight tugs are classed by Lloyd’s Register and operated by Kotug International on behalf of Pilbara Marine.
Robert Allan said it adapted its ART 80-32 design to develop the ART 85-32W design with a sponsoned hullform suited to the Rotortug concept.
“The new tug design has been modified to cope with the higher bollard pull, including 1.2 m of additional beam and increased flare,” said Robert Allan, “to provide increased stability during escorting, while also enhancing manoeuvrability.”
These tugs incorporate the patented triple Z-drive Rotortugs concept, featuring omni-directional manoeuvrability, “and the benefits of a fully redundant and precise propulsion machinery configuration” said Robert Allan. “The Rotortug concept offers increased redundancy for ship-handling and escort towing, as well as enhanced crew safety.”
Robert Allan’s ART 85-32W design has an overall length of 31.5 m, beam of 13.7 m and least moulded depth of 4.8 m.
These 497-gt tugs have an extreme draught at 125 dwt of 6.1 m
On trial, these vessels achieved ahead and astern speeds of more than 13 knots and bollard pulls in excess of 85 tonnes both ahead and astern.
Their propulsion consists of three Caterpillar 3512C HD main engines, each developing 1,765 kW at 1,800 rpm. These are compliant with IMO Tier II emissions requirements and drive three Schottel SRP 430 Z-drives. These Rudderpropellers have fixed-pitch 2.5-m diameter propellers, with two located at the fore and one at the aft.
Ibercisa supplied the deck machinery on these tugs, including forward and aft electric escort towing winches.
Each tug has fire-fighting systems, supplied by FFS, to FiFi1 class with one XPC pump driven off the front of the port forward main engine. This delivers 2,850 m3/hour of water at 110 m through two FFS1200 LB monitors that can deliver 1,200 m3/hour of water and 300 m3/hour of foam.
Fortescue procured and Damen constructed tugs:
Kotug leased and Cheoy Lee constructed tugs:
ART 85-32W particulars
Designer: Robert Allan
Class: Lloyd’s Register
Length: 31.50 m
Beam: 13.70 m
Depth (least moulded): 4.82 m
Extreme draught at 125 dwt: 6.10 m
Gross tonnage: 497
Bollard pull: >85 tonnes, ahead and astern
Free running speed: >13 knots, ahead and astern
Fuel oil capacity: 185 m3
Fresh water capacity: 26.6 m3
Main engines: 3 x CAT 3512C HD
Propulsion: 3 x Schottel SRP 430 Z-drives