Joint project tug on show at Seawork
’Taska 1’ is nearing completion at Red7’s yard in Ipswich UK.
At last year's Seawork, Red7 Marine bought a tug off the shelf from Damen. This year the East Anglia based marine construction and subsea group are displaying their own tug, under the banner of Taska Marine.
Taska Marine is a new company formed in a 50-50 partnership with Challis and Sons Ltd, boatbuilders and dredging equipment specialists from north Essex.
Red 7's order book has been growing fast, and mobilising their jack up barges at sites around the country has sometimes been delayed by the unsuitability of towing vessels. The Damen Stan Tug purchased at Seawork last year fits the bill for larger jobs but the company also needed a versatile, shallow draft vessel which could be delivered to the site by road, arriving at the same time as the disassembled barges.
The first such vessel is Taska 1, a 12m, twin screw, 430hp vessel with a maximum draft of 1.3m and a beam of 3.7m, which can be viewed at Berth 19 at Seawork 2011. Designed by Wayne Challis, the tug has been assembled by a small team at Red7's Ipswich yard, using a 'flat pack' construction method.
The vessel was designed using the Rhino 4 CAD program with Orca 3D marine add-on. The steel was supplied by Parker Steel of Canterbury in batches. First were the bare ribs and 8mm plates to deck level (including engine beds),followed by 6mm deck plates and gunnels and 5mm plates for the wheelhouse. The first steel arrived in May 2010 and the physical build of the prototype has taken one year.
‘The laser cut steel was incredibly accurate, said Wayne Challis. ‘Everything fitted perfectly’.
The CAD software has allowed Challis to calculate the strengths and stresses on every piece of steel. Depending on its known weight and position, the designer can calculate the centre of gravity, centre of buoyancy, angle of heel and stability curve, with and without fuel, fresh water, deck load etc. The MCA has monitored the build as it progresses and when complete the boat will be coded MCA workboat Code 3, 20 miles offshore, day and night.
Twin Perkins Sabre M215C engines are coupled to PRM 4:1 gearboxes driving two fixed pitch 900mm three blade propellers. The props and shafts were supplied by BT Marine of Devon, who Wayne 'discovered' at last year's Seawork. The stern tubes came from Exalto, hydraulic steering gear from Phoenix and various items of chandlery from ASAP.
The bollard pull can be calculated from the CAD program and the workshop test matched the theoretical figure for 430 hp engines with the specified props, which gave 4 ton bp. The design free running speed is 9 knots. The engines are keel cooled with side mounted exhaust exits, meaning there is no exhaust stack to interfere with wheelhouse visibility.
Taska will maintain the craft and Red7 will operate at least one of this type. The vessel type will be available for sale to third parties at a price to be announced at Seawork. In future, construction will be much quicker, with more workers involved and less design time.
by Graeme Ewens
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