The minimum film thickness and rolling traction for line contact under isothermal fully flooded grease or base oil lubrication are calculated using the TED/CPA software. By curve-fitting the TED/CPA results, an expression for the minimum film thickness of grease in the isoviscous-rigid (IVR), piezoviscous-rigid (PVR), and elastohydrodynamic lubrication (EHL) regimes is derived. Based on the proposed minimum film thickness expression for grease and the modified Moes expression, the effective viscosity of grease at ambient pressure is determined. Furthermore, it is shown that when the effective viscosity of grease is used in place of the oil viscosity at ambient pressure, isothermal rolling traction for grease lubrication in the IVR, PVR, and EHL regimes under fully flooded lubrication conditions can be accurately predicted using Ohta and Matsuyama's expression.
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