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).
Technical specification page detailing fuel properties including sulphur, freezing point, gum, and anti-detonation value.
| Identifier | ExFiles\Box 27a\4\ Scan103 | |
| Date | 28th April 1933 guessed | |
| -2- (5). SULPHUR CONTENT. There shall be a complete absence of free sulphur and the total sulphur content shall not exceed 0.10% by weight. (6). FREEZING POINT. The freezing point as indicated by the initial formation of solid shall not be higher than minus 50°C. (7). GUM. (a) EXISTENT GUM. The amount of existent gum as determined by the evaporative method in a glass dish shall not exceed 10 m.g.m. per 100 ml. (b) POTENTIAL GUM. After 50 m.l.s of the fuel have been incubated at 35°C. for 20 hours, the increase of gum yield over and above the existent gum as determined by the evaporative glass dish method shall not exceed 10 mgs. per 100 ml. (For method of determination of gum, see Appendix 1.) (8) ANTI-DETONATION VALUE. The anti-detonation value shall not be less than 80 Octane number when determined upon an Ethyl Gasoline Corporation series 30 knock testing engine equipped with standard bouncing pin, knock meter and high temperature head and operated under standard conditions in accordance with Appendix 2. The Octane number is numerically the percentage by volume of iso-octane (2,2,4 tri-methyl pentane) in a mixture of iso-octane and normal heptane. The octane number of the fuel is the octane number of the mixture of iso-octane and normal heptane which it matches in anti-detonation value. A secondary or sub-standard reference fuel may be used for purposes of matching but the sub-standard fuel must be equal in knock rating to the primary octane heptane mixture when tested under the conditions of Appendix 2. Supplies of standard or sub-standard fuels will not be issued by the Air Ministry. The Air Ministry will use a substandard, a straight run petrol of high knock rating with the addition of pure crystallisable Benzene when undoped fuels are being tested and the addition of T.E.L. when fuels containing T.E.L. are being tested. Cont'd.{John DeLooze - Company Secretary} | ||