Oil prices will continue to increase according to the current market situation, the international requirements for emission have become increasingly rigorous, and the fuel sulfur content of ships sailing in zones subject to sulfide emission control should be kept under 0.1 percent by 2015. Fuel cost and emission limit cost has put pressure on shipping companies, and diesel engine manufacturers as well. At the just-concluded 2012 China Green Ship Technology Summit, Huang Yongzhong, deputy director of the Marine Power Research and Development Institute, Yuchai Machinery Co., Ltd., noted diesel engine manufacturers would soon face the adverse situation of being forced out if they cannot achieve breakthrough in technology and design.

New product: oil-gas marine engine

Among new-fuel power products, oil-gas marine power equipment is easier to be favored by customers, and this field will gain rapid development in a short period, Huang said. Natural gas is clean and high-efficiency energy, which is not only incomparable in meeting emission requirements, but also appealing in cost compared to fuel. For oil-gas marine engines, fuel cost can decrease by 1 percent with the substitution rate of natural gas increasing by 1 percent.

Besides the advantages in reducing operating cost and producing environmental benefit, oil-gas marine engines are of great utility. On the one hand, the construction of domestic port gas stations has just started, oil-gas marine engines can use an appropriate amount of diesel to ignite gas-air mixtures, and directly use diesel oil in case of gas filling difficulty. On the other hand, oil-gas marine engines are less critical of ship modification, and are easy to be accepted by ship inspection institutions, thus opening up the market faster.

At INMEX China 2012, Guangxi Yuchai Machinery Group Co., Ltd. promoted marine power products like YC6T and YC6C. According to sources, the companys onshore gas engine technology has been mature, its corresponding products have been widely accepted in the market, and large-power oil-gas marine power products developed and manufactured on the basis of the technology is the major means of Yuchai Group to cope with new changes in the marine power market, and the group should lose no time in mass-manufacturing oil-gas marine engines during following market development.

New technology: high pressure common rail electronic injection

Durableness, energy conservation and environmental friendliness, light weight and good adaptability will become the goal of marine diesel engines. High pressure common rail electronic injection has become a key technology in the field of marine diesel engine development and manufacturing owing to many merits. According to Huang, high pressure injection can effectively reduce fuel consumption, and increasing the control accuracy of fuel charge through electronic control can reduce nitric oxide omission. Besides, the low-noise and compact common rail system can effectively reduce the dead load of the ship, optimize the compartment layout and help to reduce emission and consumption from the perspective of hull design.

However, high pressure common rail electronic injection poses higher requirements to the technologies and production capacity of diesel engine manufacturers, and have some problems pressing for solution in such aspects as equipment price, use habit, equipment maintenance and fuel quality, and is not good for popularization among customers. As Yuchais diesel engines using the technology are know only used intensively on high-end official ships, the company has planned to popularize such engines in the fields of inland carrier and fishing vessel, and to attempt to apply such engines on ocean going vessels after gaining adequate experience.

Additionally, increasing equipment liability through fresh water cooling, meeting the requirements of increasingly rigorous emission limit and engine performance through two-stage turbocharging system, and using body materials with better comprehensive mechanical performance such as alloy cast iron and vermicular cast iron have all been included by Yuchai Group in the scope of technical innovation in marine diesel engines. Recently, the company has established Dalian Yuchai Turbo Technology Research and Development Center Co., Ltd. with Dalian Jiaotong University, which will mainly engage in the design and R & D of turbo products including marine turbocharger.

(Source: China Ship News)