With reference to CIMAC, the CIMAC fuel oil standards are amended by 3 sub groups (waste oil mixing problem, fuel oil standard value at the engine inlet, CIMAC fuel oil standard) established on “Heavy Fuel”5). In Japan, the standard for the marine fuel oil was discussed at the “Working Group on ISO/JIS examination for marine fuel oil” so as to incorporate ISO 8217 into JIS, but no unanimous agreement was reached between neutral agencies, shipping companies, equipment manufacturers, and producers, and the incorporation into JIS was abandoned. For this purpose, a “Work Group on Marine Fuel” (first held in August, 1998) was newly established as an organization to summarize the Japanese draft on the amendment of the ISO Standards. In the reference published in 1998, a special issue on the NOx regulation from the exhaust gas was given, including interesting articles on the result of measurement of the exhaust gas from actual ships and the small scale denitrizing system on board actual ships6). The exhaust characteristic of particulate is also reported7) As the technical materials on the fuel oil handling equipment, selection and the use of the fuel oil purifier, and the processing capacity of the fuel oil pre-processing system are reported8).
Concerning the relationship with the fuel oil, the combustion residue of the diesel engine for marine use, the effect of the size and the fuel kind of the diesel engine on the exhaust gas emission, and the effect of the composition of the fuel oil on the combustion characteristic8),9),10). The material in which the safety in handling the fuel oil is systematically summarized is published from CONCAWE11). Concerning the problems on waste oil, the mixture of plastic is reported12).
In addition, lectures are actively held on the marine fuel oil, and the fuel and the reliability of engines, the environment, the manufacturing method, and the trend of amendment of the standards were discussed at the Lectures sponsored by the Japan Internal Combustion Engine Federation, and reported and published in “Papers on Lectures”, and “Reports on CIMAC”.
References
1) Monthly Oil Report 44-2 (1999), Petroleum Association of Japan
2) Monthly Report on Energy Trend. Products, Supply and Demand, 1998. No. 1-12, Report by the Minister' s secretariat of International Trade and Industry.
3) Report by the Japan Internal Combustion Engine Federation, 1999, January No. 75
4) Shiode, Journal of the M.E.S.J., 33-6, 387 (1998)
5) Report on The Japan Internal Combustion Engine Federation, 1998, August No. 74
6) Journal of the M.E.S.J., 33-5, 317-352 (1998)
7) Tsukamoto, et al., Journal of the M.E.S.J., 33-4, 306 (1998)
8) Journal of the M.E.S.J., 33-6, 413-424 (1998)
9) Takase, et al., Journal of the M.E.S.J., 33-4, 306 (1998)
10) Takase, et al., Journal of the M.E.S.J.. 33-3, 226 (1998)
11) CONCAWE “heavy fuel oils” product dossier No. 98/109
12) Shipp World Shipbuild, 199-4146, 37 (1998)
[Chikanobu CHINO]
9.2 Present Situation and Trends in Marine Engine Lubricants
9.2.1 Lubricating Oils for Crosshead Engines
(1) Cylinder Oil
The recent cylinder oils are SEA50 and BN70 grade and their performances are being improved in line with the increases in engine loading and the degradation of the combustion property of the fuel oil. The cylinder oil development is greatly dependent on the engine development and the trend in quality of the fuel oil, and one of the major developmental areas on cylinder oils is the improvement of the anti-wear performance. The wear of the cylinder liner and the piston ring is the mixture of the corrosive wear and the adhesive wear, and the current developmental works focus on the protection for the adhesive wear. The factors to impact on the adhesive wear include the oil film thickness, the wear protection properties of the cylinder oil, metallurgy, and the condition of the metal surface. Contribution by lubricans to reduce wear-down is to maintain the optimum oil film thickness even at the high temperature of cylinder liners, and to improve the wear protection capability. The oil film thickness is greatly influenced by the characteristic of the base oil. Single-cut highly viscous mineral base oils with good thermal stability at high temperature may be employed, so that the optimum oil film thickness can be maintained in the high temperature range. This is reflected in that the viscosity of recent cylinder oils at 100℃ have become higher. On the other hand, from the viewpoint of the boundary lubrication between cylinder liner and piston rings, there is a cylinder oil with anti-wear additive which is active even in the high temperature range and the oil contributes to the reduction of the wear-down.
