In Japan, The SRIC database system of third generation has became a useful system included over 114000 field data about the failure of ship equipment pass the long time investigation. This database system has never been carried out in other countries. And SRIC is a relational database system constructed by the some data tables and many useful functions. It become clear that the average failure rate of the whole of ship equipment was 7.2 [case/1000hr.] and the work for the repair was 5.0 [man*hr.] through the statistical analysis by SRIC. And, it is noticed that the failure ratio of miscellaneous equipment is about 43 [%] . The average failure rate is changing with same level. However, the work for repair was increasing rate from the middle of the 90s. The actual conditions for the reliability of the ship equipment gradually became clear, but the long term approach of the raise in reliability is necessary in the future. This paper reports the latest results of the statistical analysis and the multivariate analysis about the main engine system by using the information of SRIC. As a result of the cluster analysis, the reliability of the main engine system and its characteristics became clear.
An electronically controlled system for fuel injection is one of techniques to improve thermal efficiency and to reduce harmful emissions simultaneously. The authors applied an electronically controlled system to a diesel engine, a 3-cylinder medium speed 4-cycle engine of 257 kW/420 rpm at maximum continuous output power. On the system, the fuel injection pump is driven by hydraulic pressure and the hydraulic pressure line is electronically controlled to change fuel injection timing. Fuel injection profiles different from that of a camshaft are also obtained. The test engine was operated over 25% load to 100% load of maximum continuous output with a propeller law. At low load conditions, thermal efficiency, NOx emission and PM emission characteristic could be improved simultaneously, by optimization of injection timing. Regarding PM emission, it was improved drastically throughout the whole engine load range, which is considered to be caused by that the increase in pressure rising speed improved atomization characteristics at initial period of injection.
The first roro/passenger ferry in the world to be applied LNG fueled engines entered service in Norway in February, 2000. The reason applied LNG fueled engines is that the Norwegian have a sense of environment strongly, and LNG is easy enough to supply stably. LNG is composed of methane mainly, and not include sulphur. Therefore, it is possible to produce the reduced NOx, CO2 and zero SOx emissions by the LNG fueled engines. It provides the environmental benefit. The engines burn a combination of gas and air, and feature both a pre- and main chamber designed for lean gas/air ratio. The pre-chamber technology ensures very low NOx level. The low NOx emission achieves below of 150 ppm and 10-20 percent drop in CO2 in comparison with oil engines. This paper describes an outline of the ferry applied LNG fueled engines, a demand for the engine and an outlook for LNG powered ships.