NOVEMBER 26, 2014 — Classification society ClassNK has approved the design of a new 28AHX-DF dual-fuel engine developed by Niigata Power Systems Co., Ltd. After trial operational testing, the engine is expected to receive type approval from ClassNK in December.
The new engine is slated to be used as the main engine on a new LNG fueled tugboat being built by shipbuilder Keihin Dock Co., Ltd. for NYK Line that will be Japan's first LNG fueled vessel, other than LNG carriers (see earlier story).
Niigata's 28AHX-DF is a medium-speed dual-fuel engine with a maximum rated power per cylinder of 320 kW, a maximum rated speed of 800 rev/min, a cylinder bore of 280 mm and a 390 mm stroke. It has been developed for use primarily in offshore support vessels and tugboats.
The engine, which operates on both diesel fuel and LNG, will meet the strict 0.1% sulfur emissions regulations in the ECA that are set to go into effect in 2015 and will also comply with the IMO's Tier III NOx emission requirements.
Technologies used in the new engine were developed with the support of Japan's Ministry of Land, Infrastructure, Transportation & Tourism (MLIT), as well as ClassNK as part of the society's Joint R&D for Industry Program.
Mr. Yukihisa Shibata, General Manager of ClassNK's Machinery Department said: "The demand for dual-fuel engines is increasing as IMO restrictions tighten and the industry recognizes the importance of environmental accountability. Supporting the development of such low-emission engines is one way we can help ship operators and manufacturers practically address the challenges of these new regulations, and encourage the wide spread use of this new technology."