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Automotive Crankcase Oils
Published in Leslie R. Rudnick, Synthetics, Mineral Oils, and Bio-Based Lubricants, 2020
Lubricity is a measure of the effect of a lubricant on the coefficient of friction of a contacting part with a sliding surface. In engine oils, greater lubricity would impart improved fuel economy and lower frictional power loss. Fuel economy as measured in the Sequence VI, VIA, and MB M111 fuel economy tests is heavily influenced by the oil viscosity. Lubricity does have an effect with the addition of friction modifiers showing some improvement. Friction modifiers include some carboxylic acids, sulfurized fatty acids, glycerol monoesters, and oleate esters.
Tribology of the Wheel-Rail Contact
Published in Simon Iwnicki, Maksym Spiryagin, Colin Cole, Tim McSweeney, Handbook of Railway Vehicle Dynamics, 2019
Ulf Olofsson, Roger Lewis, Matthew Harmon
The key characteristics required of a lubricant are as follows [68]: Lubricity or the ability of the lubricant to reduce friction (although the effect on wear is of greater importance).Retentivity or the measure of time over which the lubricant retains its lubricity. Flash temperatures in the wheel-rail contact can be as high as 600°C to 800°C, and these lead to the lubricant in the contact being burned up. The retentivity is therefore a function of the loads and creepages seen at the lubrication site, as these dictate the temperature in the contact.Pumpability or how easily the lubricant can be applied to the track. The temperature is an issue here, as some track locations will experience a wide range across which some lubricants may not maintain their pumpability. Some networks use different lubricants in the winter and summer for this reason.
Diesel Fuel
Published in Mark J. Kaiser, Arno de Klerk, James H. Gary, Glenn E. Hwerk, Petroleum Refining, 2019
Mark J. Kaiser, Arno de Klerk, James H. Gary, Glenn E. Hwerk
Diesel fuel functions as a lubricant in most components of fuel injection equipment such as pumps and injectors. Lubricity is the ability to reduce friction between solid surfaces in relative motion. Two fuel characteristics affect equipment wear, low viscosity, and lack of sufficient quantities of trace components that have an affinity for metal surfaces.
Friction and wear characteristics of rice bran oil based biodiesel using calcium oxide catalyst derived from Chicoreus Brunneus shell
Published in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2019
Hoora Mazaheri, Hwai Chyuan Ong, H. H. Masjuki, A. Arslan, Wen Tong Chong, Zeynab Amini
The most prevalent method to generate biodiesel is transesterification of oil triglycerides using alcohol and catalyst. With development of technologies and fast modernization, fuel is necessary to supply both the energy and lubricity (Kesić et al. 2016). Lubricity has an important effect on the quality of the fuels. In order to have prolonged machine life, it’s important to consider the lubricity as it protects the moving surface against wear. Good lubricity will also result in reduced energy consumption as it decreases the friction of automotive parts (Masood et al. 2012; Mosarof et al. 2016a). It has been made known that neat biodiesel presents considerable lubricity than petrodiesel (Singh, Kumar, and Chandra Sharma 2019). Tribological attributes of assorted biodiesels have been examined by many researchers. In a study conducted by Habibullah et al., diesel was reported to have elevated friction coefficient and wear scar diameter, 16% and 40%, respectively (Kesić et al. 2016). Furthermore, Fazal et al. examined the tribological attributes of palm oil-based biodiesel and they claimed that after they increased the biodiesel quantity, they observed that the wear and friction diminished (Tan et al. 2019). According to Sulek et al., when 5% rapeseed biodiesel mixed with 95% diesel and pure biodiesel was used, friction coefficient of diesel dropped to 20% and 30%, respectively (Lani et al. 2017). Although there have been a lot of studies in this field, there is no research on tribological characteristics of RBO biodiesel utilizing Chicoreus brunneus shell-based catalyst. The current study is conducting investigation on the tribological characteristics of this biodiesel. Additionally, various blends of biodiesel and petro diesel were implemented in order to examine how biodiesel concentration exerts influence on the tribological properties.