Grampian Talisman IMT 978 Platform Supply Vessel and will get its sister next year. We have also taken five modern IMT 948 ERRVs over the last two years," he explains. "We will get the two more of those this year. We want to give our clients, who are the major oil companies, cost-effective vessel solutions. This flexible modern fleet means we can offer a mix of support to suit their needs. We have had 11 vessels designed by IMT and all built at the north Spanish yard of Balenciaga, and IMT has been good at understanding our needs and providing us with robust solutions. We also appreciate their ability to deliver costeffective vessels with reduced fuel consumption and a good environmental footprint." The IMT978 design is 78.2 m LOA and 17 m beam, giving a good load area and a stable work platform. The molded depth is 7.2 m, and deadweight on a summer draft of 5.82 m is 3,614 tons. That deadweight includes the possibility for 1,300 tons of deck cargo secured on the 739 sq. m. of deck space, which has a load capacity of 5 t/sq. m. The rest of the cargo is in flexible below deck spaces which include 1,480 cu. m. for fuel oil, 790 cu. m. for potable water, 940 cu. m. (10 tanks two grades) for liquid mud, 940 cu. m. (10 tanks two grades), 376 cu. m. for brines (two grades), 262 cu. m. (5 tanks two grades) for dry bulks, 230 cu. m. base oil, 1210 cu. m. for drill/water ballast and 402 cu. m. for recovered oil. Patterson says, "This is in many ways a simple vessel, but it takes a lot of good design work to create a vessel which can meet all the needs. First we had to go for a high block co-efficient for the hull, to get the load carrying capacity needed. That gives the problem of how to make the hull easily driven. We solved that by adopting what we call an Icelandic bulbous bow. Effectively it is a bulb which extends almost right up to the bow flare, and we tried several versions of that in model tests until we got the final bulb shape. It makes the vessel look very distinctive, which is nice, but above all it makes the basically box-shaped hull easier to push through the water. That saves fuel, cuts emissions, and gives the vessel excellent sea keeping qualities." The next small but important difference between the IMT978 and a standard PSV is the slightly larger accommodation, which in turn is pushed right forward. The Grampian Talisman provides the high stan-
dard of accommodation expected on European supply vessels, with provision for 18 crew in single ensuite cabins, two lounges, offices, mess room and Standby Accommodation to UKOOA requirements. "We have a spoon bow to allow us to push the accommodation block right forward," said Patterson. "The block itself is slightly longer than on a typical PSV to allow us to fit in the full survivor accommodation so that the vessel can act as a standby and ERRV vessel if required. And that accommodation itself can also be converted to use for survey equipment and staff if the vessel is to be used in a survey role." The longer accommodation allows for space on the starboard side for a daughter craft that can be fitted for the Field Support role. As delivered the IMT978 has one Fast Rescue Craft mounted to port, but it is fully dimensioned to carry a daughter craft to starboard. "We looked closely at the propulsion systems," said Patterson. "We had pioneered diesel-electric for standby vessels, but to achieve the required under deck capacities for this vessel it was more efficient to adopt a conventional twin engine CPP installation. At present the vessel is on long-term charter to Talisman Energy used as a pure load carrier, back and forth from the field, so a conventional engine layout can operate very efficiently and has the advantage of lower capital costs. The thruster configuration however, provides flexibility to allow the vessel to operate in standby or survey roles for long periods." Propulsion, maneuvering and power supply is from two Caterpillar-MAK 6M25 2,800 bhp @ 750 rpm main engines driving 2 x 3000 mm diameter CPP Propellers through two reduction gearboxes. There are two 1500 kW Stamford Shaft Alternators and two 330 kW Cat 3406 diesel alternators. DP2 and three position joystick maneuvering is achieved with two 800 bhp Bow Tunnel CPP thrusters supplied by Schottel, two 800 bhp Stern Tunnel CPP thrusters and two Independent Fishtail type rudders. Trial speed was 14 knots but service speed is around 12.5 knots. "The IMT978 is the product of a close relationship between an owner who has specific needs and a designer who wants to meet those needs at a costeffective price. This vessel will give versatile service and compete with fancier vessels, and we are very pleased with it," says Patterson.
October 2007
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