Tug Technology & Business gained exclusive access to the above- and below-deck technology on one of Damen Shipyards Group’s latest azimuth stern drive tugs
Damen Shipyards Group has designed its latest batch of azimuth stern drive (ASD) tugs to be crammed full of powerful engines and generators. These drive two Rolls-Royce propulsors to generate 70 tonnes of bollard pull for escort and harbour operations.
These were some of the systems that were highlighted to Tug Technology & Business during an exclusive tour of the latest of these tugs to come off the Damen production line. The tug tour was conducted during a visit to Albwardy Damen’s shipyard in Sharjah Hamriyah Freezone, in the United Arab Emirates.
This ASD 2411 design, ASD 92 tug incorporates the latest hull and skeg designs and the most recent developments in propulsion, wheelhouse and winch design. It is one of a series of tugs built as stock vessels and available to purchase.
Albwardy Damen project manager Sajan Karolkuni explained that the ASD 2411 design tug is 24.4 m long and 11.3 m wide and has been designed for manoeuvring ships in terminals and harbours and for vessel escort work. He said one of the key elements in the design and construction was to generate as much bollard pull as possible without jeopardising the tug’s size or manoeuvrability.
Its power comes from two Caterpillar 3516C engines that have a total power of 4,200 kW at 1,600 rpm. These drive two Rolls-Royce US 255 azimuthing thrusters with fixed pitch propellers of 2,600 mm diameter.
Auxiliary equipment on the ASD tug includes two Caterpillar C4.4 TA main generator sets that each produce 86 kVA, with 230/400 V at a frequency of 50 Hz. Other equipment includes two general service pumps, two fuel oil header pumps, three bilge water pumps, a water separator and a Rickmeier lubricant oil pump.
Mr Karolkuni also pointed out that the fire-fighting (FiFi) pump for the tug’s FiFi 1 system was located centrally in the engineroom. This diesel-driven pump can deliver 2,700 m3/h to two electrically-controlled monitors, which can deliver 1,200 m3/h each and to two waterspray units that each have a 150 m3/h capacity. This system was delivered by Fire Fighting Systems.
While the FiFi 1 system should only be needed in an emergency, another part of the deck equipment is designed for daily tug operations. Mr Karolkuni explained that the DMT-supplied double-drum winch near the bow of the vessel has 68 tonnes capacity and can be used with a tie-bit for harbour operations. There is also an electrically-driven capstan and 100-tonne towing hooks fore and aft.
Around the deck is a set of fenders. At the bow there is a combination of cylinder and block fenders, while there are D-shaped fenders on the side and aft of the tug and cylinder fendering at transom corners.
The whole of the tug is controlled by an automation system supplied by Praxis, which also provided a digital display and controls on the switchboard and outside the master’s cabin. The rest of the switchboard was supplied by Alewijnse Marine.
Automation data can also be displayed on an integrated bridge in the wheelhouse. This has 360 degrees of view for the master with a swivel chair that provides access to tug controls and workstations.
Furuno Electric supplied most of the bridge equipment in ASD 92. The Japanese company supplied radar, echosounder, speed log, automatic identification system and a differential satellite-based positioning unit.
“The displays can be configured for different information requirements, such as conning, tug alarms, fuel consumption, electric generators and diagnostics,” Mr Karolkuni said. It can also display information about the tug’s pumps, ventilation, lighting and fuel levels.
“There are two of these for redundancy and overhead dials that include compass and propulsion information,” he explained. Communications equipment on the tug includes two Sailor Compact 6222 VHF radios from Cobham Satcom and two Tron TR-20 handheld VHF radios from Jotron. This company also supplied the emergency radio beacon and search and rescue transponder. Propulsion controls are supplied by Rolls-Royce, while Schneider Electric provided the winch controls.
This ASD 2411 is a similar design to two tugs that are to be built by Wilson Sons Estaleiros yard in Brazil for Saam Smit Towage. These are scheduled to be delivered in the middle of 2018.
It is also similar to tug Columbia, which was delivered to Italian owner Rimorchiatori Riuniti in May this year for harbour operations in the Mediterranean region. This also had 70 tonnes of bollard pull.
Damen’s ASD 92
Design: ASD 2411
Bollard pull: 70 tonnes
Total power: 4,200 kW
Length: 24.4 m
Beam: 11.3 m
Engines: 2xCat 3516C
Thursters: 2xRolls-Royce US 255
Winch: DMT, 68 tonnes
Switchboard: Alewijnse Marine
On the bridge:
Search light (FiFi 1): 2x Pesch, 450 W, Xenon
Radar system Furuno FAR-2117
Propulsion controls Rolls-Royce
Winch controls Schneider Electric
Autopilot Robertson AP-70
DGPS Furuno GP-170D
Echosounder Furuno FE-800
VHF 2x Sailor Compact 6222
VHF (hand-held) 2x Jotron TRON TR-20
Compass 2x Magnetic, Kotter type
Speed log Furuno DS-80
Navtex Furuno NX-700
AIS Furuno FA-150
EPIRB Jotron Tron-60S
SART Jotron Tronsart20
Anemometer: Observator Windsonic OMC 115