Rolls-Royce reported that it produced its 6000th reciprocating engine during 2008 and its plans for future engine deliveries are based around the “clean design” standard. The 6000th engine, equivalent to 50 000 cylinders, produced by Rolls-Royce at its Bergen, Norway, facility left the production line destined for a cogeneration plant in Andalusia, Spain. The B35:40V gas engine is one of three providing power for an olive oil processing plant.
This milestone comes in a year when Rolls-Royce expects to produce its highest ever quantity and value of engines. A record-breaking 208 engines were delivered in 2007 and the company is ontarget to hit an even higher number this year.
The company said that the technology that has gone into all of these engines is going a step further with the introduction of the clean design standard. The aim is to reduce pollution from harmful nitrous oxides emitted by the company’s marine engines by 4.6 million tonnes each year. This achievement is the result of Rolls-Royce innovations that ensures marine engines will meet Clean Design standards to be set by the International Maritime Organization, IMO. Rolls-Royce began working on a package of improvements to reduce NOx emissions well in advance of the 2005 introduction of Clean Design standards by one of the leading International marine classification societies, Det Norske Veritas (DnV).
By next year Rolls-Royce expects around 90% of all its engines built will meet the standards of the clean design classification. Currently the Clean Design capability focuses on the Bergen B32:40 engine, but next year the C25:33L eight- and nine-cylinder engines will also meet the environmental standards. The company announced during 2008 that this engine, first introduced to the marketplace in 2002, will be built to meet IMO NOx targets, and its power output increased to 330 kW per cylinder.
The reduction in NOx is achieved without loss of efficiency, Rolls-Royce reported. This improvement is a result of the application of the Miller cycle, in combination with an increase in compression ratio. To avoid low-load smoke and poor transient load behavior in the low-load range, which are negative consequences of the Miller cycle, the engines are equipped with variable valve timing mechanisms by which the Miller cycle inlet air valve timing may be turned off for low-load running.
At the same time the output of the C25:33 ranges have also been increased to 330 kW/cyl without changing engine speed or sacrificing the engine’s clean design capabilities. Almost 3000 kW is therefore now available from a compact nine-cylinder engine. This has been done by using advances in turbocharger technology allowing higher pressure ratios, with some changes in engine parameters. The engine structure had plenty of built-in design-stretch to allow for uprating. Mean piston speed remains the same at 11 m/sec, while the BMEP is now 24.7 bar at 1000 r/min and 26.4 bar for 900 r/min engines, while the specific fuel consumption is unchanged at 190 g/kWh at full load, excluding engine-driven pumps.
A number of uprated C-series engines were ordered during 2008, including 14 for seven UT 755 LN supply ships to be built in India. Each vessel will have a pair of six-cylinder C25:33 L6P engines delivering 2000 kW per engine. Following the success of gas-fueled versions of the company’s K and B series engines, a gas version of the C series is also now under development. Gas engines with six, eight and nine cylinders, inline, will be derived from the diesel engine, with initial deliveries in about two years time.
The environmental efforts of Rolls- Royce were rewarded during 2008 with an accolade for its work on liquefied natural gas (LNG) fueled gas engine technology. This is bringing major cuts in emissions of carbon dioxide and oxides of nitrogen on intensively used ferry routes off the west coast of Norway. The award relates to five Rolls-Royce powered ferries operating on two heavily used routes providing main road connections using LNG as fuel.
In India, Rolls-Royce officially opened its marine service center at Maharashtra Industrial Development Corp. in Turbhe, Navi Mumbai. The center will offer support services and undertake repair and upgrading of the company’s marine products and equipment in the region.