Gear lubricants performance

These classes of compounds were the first used during the industrial revolution to improve the performance of machinery and were developed to improve the scuffing load of gear lubricants. Examples of typical structures of sulphur/nitrogen compounds which have found application are given in Fig. 3.12. 

Uses Dispersant, wetting agent for acidic carbon bik. and phthalo pigments in solv.-based coatings and inks dispersant in syn. lubricants, e.g., high-pressure gear lubricants, high performance industrial lubricants... 

Bala, V. 2003. Gear lubricants. InFuels and Lubricants Handbook Technology, Properties, Performance, and Testing, Vol. 16. ed. G.E. Totten, ASTM International, West Conshohocken, PA, pp. 431-464. 

Adams, J. H., and Godfrey, D., Borate gear lubricant - EP film analysis and performance, Lubr. Eng., 37 (1981) 16-21. 

The model has been applied successfully to predicting the performances of bearings, gears, seals, and engines [10-12]. A fundamental limitation of the statistic models is their inability to provide detailed information about local pressure distribution, film thickness fluctuation, and asperity deformation, which are crucial for understanding the mechanisms of lubrication, friction, and surface failure. As an alternative, researchers paid a great interest to the deterministic ML model. 

The input speed to the gear train was varied from 1500 to 4500 rpm, the torque from 0.025 to 0.5 Nm, and the contact load on the idler gears from 0.5 to 30N. The peripheral speeds of the gears were up to 3.3 ms , the relative slip 1 ms and the maximum contact stress 900 MPa. The test temperature was varied between 20°C and 250 C, and the chamber pressure was 10 Torr. 24 lubricating gears containing different proportions of copper, silver and molybdenum disulphide were tested, and the best performance was given by a composite of 87% copper, 5% silver and 8% molybdenum disulphide. 

Vaisfeld, L.O., Work Performance of Gear Transmissions with Magnetic Powder Lubrication under Various External Conditions, Russian Eng. J., 59, 8, (1979). 

Over the years, detergents have found equally important usage in many other types of lubricants, including gear oils, farm tractor hydraulic fluids, automatic transmission fluids and industrial oils. The performance properties that detergents impart to these lubricating fluids include rust and corrosion prevention, improvement in lubricant elastomeric seal compatibility, enhancement of sludge control under oxidative conditions and improvement of wet clutch and wet brake friction level and stability. 

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