The construction of the world’s first 45-centimetre-bore, ultra-long-stroke, low-speed engine, the MAN B&W 5G45ME-C9.5, was successfully finished by STX Heavy Industries, after a Type Approval Test (TAT). The engine features a fully electronically-controlled system that optimises the energy-efficiency and sustainability of the ship. According to MAN Diesel & Turbo, the G45 engine will be an excellent choice for smaller, oceangoing vessels.
In the development of the new engine design, the construction works were mainly directed at reducing exhaust-gas emissions to a minimum level and increasing fuel economy using a fully electronically controlled system.
The engine was ordered by Odfjell, which is a leading company in the global market for the transportation and storage of bulk liquid chemical products. It is the first in a series of eight individual main-engines bound for vessels, which are now under construction by NanTong Sinopacific Offshore & Engineering Shipyard in China.
The Type Approval Test was attended by several classification societies and ship owners and was performed at Changwon plant of STX Heavy Industries.
As an illustration of a typical application for the new engine type G45, the MAN Diesel & Turbo offers an example for the engine installation aboard an 800 TEUs container ship. The characteristics are as follows:
- For an 8-metres vessel’s design draught, a 5,7 metres four-bladed propeller could be used in the working process;
- The usage of this propeller ensures a service speed of 17 knots;
- Approximately 105 rpm SMCR engine speed would be optimal and the SMCR power would be near 6,070 kW (with a 15% sea margin and 10% engine margin);
- At a normal continuous rating of 5,465 kW, a typical, modern, low-speed engine would have a specific fuel-oil consumption of 166 g/kWh, resulting in a daily fuel-oil consumption of 24.2 t/day.
With the implementation of the MAN B&W 6G45ME-C9 unit using these parameters, the specific fuel-oil consumption would be 161.4 g/Kwh, which means a significant reduction of 2,85% in the daily fuel-oil consumption.
Company engineers involved in the project said that additional improvements could be gained by increasing the propeller diameter from 5.7 to 5.9 metres to make use of the G-engines lower shaft-speed range, thus the optimal propeller speed would then become 97 rpm. The larger propeller ensures a reduction of approximately 1 % in the power requirement for 17 knots, which means additional fuel savings if a G-engine is applied.