The Benefit of using Group II Base Oils in Medium Speed Engines
Group II base oils are a category of base oils defined by the American Petroleum Institute as having a sulphur content less than 300ppm, a saturates content greater than 90% and a viscosity index of between 80 and 120. Group II base oils have been used in automotive lubricants for many years. This was driven by the need to improve performance of the lubricant to meet the demands of new engine technologies. As a consequence, the supply of Group II base oil has been increasing and the capacity of Group I base oil is forecast to decrease. So far, these trends in base oil capacity have left the lubricants for medium speed marine engines unaffected; such lubricants have historically always used Group I base oils as the diluent for the additive system. With increasing availability of Group II base oils, there is now a drive to utilise them for medium speed marine engine applications. The current economic climate is a strong motivator for the ship owner/operator to scrutinise their operation and identify where further cost savings can be made. Hence there is a desire for reduced oil consumption and increased power output. Combine this with increasingly poor heavy fuel oil quality, to which medium speed engines are sensitive, and it becomes clear that the demands on the lubricant are increasing. This paper discusses whether the use of Group II base oil can go some way to meeting those demands, by providing improved oxidation resistance, viscosity control and lower volatility. An upgrade of these performance features would extend the time before condemning limits for the oil are reached. The capability of these base oils in comparison to Group I is examined in bench and laboratory engine testing. The deployment of a Group II based lubricant in the field, and what benefits have been observed, is discussed.
Laura Gregory
Infineum,England
国际会议
上海
英文
1-9
2013-05-13（万方平台首次上网日期，不代表论文的发表时间）