The elastohydrodynamic (EHD) film-forming properties of several refrig
eration oils placed in pressurized refrigerant environments were inves
tigated by an interferometric EHD tester equipped with a pressurized v
essel. It has been shown that the oils with dissolved refrigerants for
med EHD films at the point of contact in the same manner as lubricant
base fluids. It was also found that greater amounts of dissolved refri
gerant in the oil decreased not only the viscosity but also the viscos
ity-pressure coefficient of the oil. In this paper, the authors descri
be a method to predict the viscosity-pressure coefficient of oils with
dissolved refrigerants.