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Formulation Technology for Low Phosphorus Gasoline Engine Oils
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Abstract
The effect of phosphorus concentration in gasoline engine oils on the valve train wear was experimentally investigated by using the JASO M328-91 3A valve train wear (3A-VTW) test method. The phosphorus concentration is determined proportionally to the amount of zinc dithiophosphate (ZDDP), which is formulated as both antiwear agent and antioxidant.
Lower concentrations of ZDDP generally bring about larger wear in the valve train. However, it was found from the experiments that valve train wear remained low despite a decrease of phosphorus concentration when secondary ZDDPs with short alkyl chain together with appropriate ashless dispersants were selected.
Since adsorptivity of secondary ZDDPs with short alkyl chain lengths onto rubbing metal surfaces is higher than that of primary types, the secondary types give excellent antiwear characteristics.
Ashless dispersants deteriorate the antiwear performance of ZDDPs because the amount of ZDDPs adsorbed onto metal surface is decreased by their complex formation with ashless dispersants in oil. Therefore, the complex formation was investigated quantitatively to optimize the type and dosage of ashless dispersants.
Based on the present work, a low phosphorus SG EC II SAE10W-30 oil which meets 1990 ILSAC GF-1 specification was successfully developed. The newly developed oil was found to provide excellent wear protection in the JASO 3A-VTW test.
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Shiomi, M., Mitsui, J., Akiyama, K., Tasaka, K. et al., "Formulation Technology for Low Phosphorus Gasoline Engine Oils," SAE Technical Paper 922301, 1992, https://doi.org/10.4271/922301.Also In
References
- Okada M. “The Effect of Engine Oil Additives on the Durability of Automotive Catalysts” Oct. 5 1984 SAE Fuels & Lub. TC-1 Forum
- Inoue K. et.al. “Effects of Phosphorus and Ash Contents of Engine Oils on Deactivation of Monolithic Three-Way Catalysts and Oxygen Sencors” SAE Paper 920654
- Burrows A.L. et.al. “Formulation of Lower Phosphorus Passenger Car Oils” SAE Paper 860373
- Takano T. et.al. “Evaluation of Passenger Car Gasoline Engine Oils by JASO Test Procedure - Report by JASO Engine Oil Subcommittee” SAE Paper 872122
- Hsu S. M. et. al. “Evaluation of Automotive Crankcase Lubricants by Differential Scanning Calorimetry” SAE Paper 821252
- Ku C. S. Hsu S. M. “A Thin-Film Oxygen Uptake Test for the Evaluation of Automotive Crankcase Lubricants” Lub. Engineering 40 75 1984
- Roberts D. C. Tournier M. “The Influence of Engine Oil Formulation on the Prevention of Valve Train Wear in Modern European Passenger Cars” SAE Paper 810328
- Rowe C. N. Dickert J.J. “The relation of Antiwear Function to Thermal Stability and Structure for Metal O,O-dialkylphosphorodithioates” 1965
- Born M. et.al. “The Relationship between Chemical Structure and Effectiveness of Some Metallic Dialkyl- and Diaryl-dithiophosphates in Different Lubricated Mechanisms” Lub. Sci. 4-2 93 1992
- Torii K. et. al. “Anti-Wear Properties of Engine Oils - Effects of Oil Additives on Valve Train Wear” SAE Paper 770635
- Matsuoka M. et.al. “The Determination of Additive Effects in a Japanese Valve Train Wear Test Using an Orthogonal Statistical Design” SAE Paper 831761
- Heilweil I. J. “Association Studies of Metal O,O-Dialkylphosphorodithioates” 1965
- Gallopoulos N.E. Murphy C. M. “Interaction between a Zinc Dialkylphosphorodithioate and Lubricating Oil Dispersants” ASLE Trans. 14 1 1971
- Shiomi M. et.at. “Interaction between Zinc Dialkyldithiophosphate and amine” Lub. Sci. 1-2 131 1989