The RT-flex common-rail technology brings benefits to ship owners in terms of great flexibility in engine setting for lower fuel consumption, lower minimum running speeds, smokeless operation at all running speeds, and better control of other exhaust emissions. The RT-flex common-rail technology will also play a key role in meeting the need for tighter emissions control under the forthcoming IMO regulations.
The ore carriers will be built by Rongsheng Shipbuilding & Heavy Industries of China. Each vessel will have a 7-cylinder Wärtsilä RT-flex82T low-speed engine with a contracted maximum continuous power of 29,400 kW at 76 rpm. The first of the ships is due for delivery in early 2011 and the twelve ships are expected to be completed in 2012.
The twelve engines will be built by Hefei RongAn Power Machinery Co Ltd (RPM) of under licence from Wärtsilä.
Both Rongsheng Shipbuilding & Heavy Industries and Hefei RongAn Power Machinery Co Ltd are members of Jiangsu Rongsheng Heavy Industries Group Co Ltd (RSHI). The licence agreement between Wärtsilä and RSHI for the manufacture of Wärtsilä low-speed engines was announced in March this year.
The Wärtsilä RT-flex82T engine is one of four new engine types introduced by Wärtsilä, all of 820 mm cylinder bore. It combines the benefits of both the electronically-controlled RT-flex common-rail system and up-to-date parameters to deliver optimum propulsion plants for ships such as these very large ore carriers (VLOC).
Largest dry bulk carriers ever built
The vessels, with each having capacity of 400,000 dwt, will be the largest dry bulk cargo carriers ever built, and will be employed on a shuttle service carrying iron ore to East Asia. The ships will contribute to reducing the cost of long-haul maritime transportation of the iron ore to steelmakers.