From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Analysis and comparison of four different oils based on their chemical properties and corrosive potential.
| Identifier | ExFiles\Box 114\1\ scan0188 | |
| Date | 31th March 1939 guessed | |
| (3). Hypoid oil compares favourably with Wakefield's oil from the corrosion standpoint, we consider, however, the large amounts of deposit thrown down by the oil, when heated, to be an undesirable feature in view of the likelihood of the deposit choking oil passages etc. Since some of this deposit was formed on the test specimens during the corrosion tests, it is probable, from a consideration of the figures given herewith, that this oil is a little less corrosive than Wakefield's The silica (Grit) content (.04%) was high compared with the other oils. We consider the T.E.X. oil to be the best of the four as regards freedom from corrosive compounds (chlorides) Analyses. | | GX. | Wakefield's Hi-press. | Vacuum Hypoid. | Vacuum T.E.X. | |---|---|---|---|---| | Sp.{Mr Spinney} gr.{George Ratcliffe} @ 60°F.{Mr Friese} | 0.932 | 0.905 | 0.940 | 0.902 | | Open flash point °C. | 177 | 288 | 199 | 263 | | Mineral Acidity | nil. | nil. | nil. | nil. | | Organic Acidity (oleic %). | 0.20 | 0.42 | 2.28 | 0.34 | | Saponification Value %. | 2.44 | 2.46 | 4.64 | 0.23 | | Chloride % | 0.97 | 0.11 | 0.04 | 0.01 | | Total Sulphur % | 0.88 | 0.64 | 2.07 | 0.55 | | Sulphur Chloride % | 1.85 | 0.21 | nil | nil | | Free Sulphur % | nil | 0.54 | - | - | | Lead % | nil | nil | 1.25 | nil | | Ash content % | 0.016 | 0.013 | 1.78 | 0.006. | | ||