A 127m-long landing ship tank vessel ordered from South Korea’s Hanjin yard will be powered by a combined diesel and diesel (CODAD) twin-screw propulsion plant based on MAN Diesel & Turbo’s high performance 280mm-bore V28/33D STC medium speed engines.
Four V12-cylinder models, each rated for 5,460kW at 1,000 rpm, will be arranged in pairs to drive CP propellers via twin input/single output reduction gearboxes. A 10 per cent overload capacity can be tapped for one hour in six.
The engines – first fruit of a V28/33D production licence between the German designer and Korean partner STX – are due for delivery in October 2012, the LST-II vessel project scheduled for completion in September 2014.
The STC designation of the engine denotes its sequential turbocharging system, which underwrites a large torque envelope. The other engine characteristics cited include: fast acceleration, lower fuel consumption, lower signature at intermediate and low loads, shock resistance, elastic mounting for low noise and vibration, and IMO Tier II emissions compliance.
* The V28/33D engine platform combines the highest unitary displacement in its class (20.32 litres per cylinder) with one of the most compact dimensional envelopes, MAN Diesel & Turbo claims. Excellent power-to-weight and power-to-installation space ratios are said to make the design equally well suited to fast monohull and multi-hull craft, offshore patrol vessels with single engine-gear-propeller systems or corvettes, frigates and destroyers with combined propulsion plant configurations (such as CODAD, CODOG and CODAG) or as a main genset drive in diesel-electric installations.
The highest power density in the speed class results in rated outputs of 5,460kW, 7,280kW and 9,100kW at 1,000 rpm respectively from the V12, V16 and V20-cylinder versions of the standard V28/33D model. With a 10 per cent overload possible for one hour every six hours, these ratings rise to 6,000kW, 8,000kW and 10MW at 1,032 rpm (equating to an output of 500kW per cylinder).
MAN's TCA33 model axial turbocharger was specifically designed to meet the needs of the V28/33D engine, which is boosted by a pair of these units. A 52-degree V-cylinder bank facilitates a centrally mounted intercooler assembly to minimise engine height and ease installation. Aluminium alloy materials are used where possible for components to secure a power-to-weight ratio below 5.1kg/kW. MP