Dimensions and weights
All dimensions are in millimetres and are not binding. The engine weight is net in metric tonnes (t), without oil and water, and is not binding.
Fuel consumption
All brake specifi c fuel consumptions (BSFC) are quoted for fuel of lower calorific value 42.7 MJ/kg (10 200 kcal/kg), and for ISO standard reference conditions (ISO 15550 and 3046).
The BSFC fi gures for Wärtsilä engines are given with a tolerance of +5%. Wärtsilä RT-flex engines have a lower part-load fuel consumption than the corresponding Wärtsilä RTA engines.
The brake specific fuel consumptions (BSFC) for Mitsubishi UEC engines (except the UEC50LSE) are based on ISO standard reference conditions with a tolerance of 3%. BSFC figures under compliance with IMO-NOx (2000) regulation are different from the figures stated in this catalogue depending on engine type, rating point, etc. For definite values, please contact the engine manufacturer.
The values of power in kilowatts and fuel consumption in g/kWh are the standard figures, and discrepancies occur between these and the corresponding brake horsepower (bhp) values owing to the rounding of numbers. For definitive values, please contact our local offices.
ISO standard reference conditions
Total barometric pressure at R1 ............................................ 1.0 bar
Suction air temperature ............................................ 25 °C
Relative humidity ............................................ 30%
Scavenge air cooling water temperature:
- with sea water .................... 25 °C
- with fresh water .................. 29 °C
Raiting points for Wärtsilä - Low-speed engines
The engine layout fields for Wärtsilä lowspeed engines are defined by the power/speed rating points R1, R2, R3 and R4 (see diagram left - click the picture to enlarge it). In certain engines, the layout field is extended to the points R1+ and R2+. R1, or R1+ instead if applicable, is the nominal maximum continuous rating (MCR). Any power and speed within the respective engine layout field may be selected as the Contract-MCR (CMCR) point for an engine.
Rating points for Mitsubishi - UEC low-speed engines
The engine layout fi elds for Mitsubishi UEC engines are defi ned by the power /speed rating points P1, P2, P3, and P4 (see diagram left -click the picture to enlarge it). Any power and speed within the respective engine layout field may be selected as the Contract-MCR (CMCR) point for an engine.
Cylinder lubrication
The load-dependent accumulator cylinder lubricating system has proven reliable operation since its introduction in the 1970s. It is employed as standard on Wärtsilä RTA low-speed engines of smaller bore.
To enable lubricating oil feed rates to be reduced the accumulator system has been further developed in recent years. The new Pulse Lubricating System with electronic control of lubrication timing has been developed. It is available for all Wärtsilä RT-fl ex low-speed engines and for selected RTA engines. The guide lubricating oil feed rate with the Pulse Lubricating System is 0.7–0.8 g/kWh. This allows important savings in engine operating costs.
For further information on this subject, please consult your nearest Wärtsilä company.
