HFO, RFO
Fuel oil is a fraction obtained from petroleum distillation, either as a distillate or a residue. Fuel oil is classified in six classes, numbered 1 through 6, according to its boiling point, composition and purpose.
In fuel oil, the viscosity is highly significant since it indicates both the relative ease with which the oil can be pumped, and the ease of atomization. Density alone is of little significance as an indication of the burning characteristics of fuel oil. Used in conjunction with other properties, it is of value in mass-volume relationships and for the specific energy of an oil.
Viscosity classification according to ASTM D396.
| Fuel Oil | Kin. Viscosity [mm²/s] at 40°C | Kin. Viscosity [mm²/s] at 100°C | API Gravity °API |
|---|---|---|---|
| No. 1 | 1.3 ... 2.1 | − | 38 ... 45 |
| No. 2 | 1.9 ... 3.4 | − | 30 ... 38 |
| No. 4 light | 1.9 ... 5.5 | − | 24 ... 28 |
| No. 4 | 5.5 ... 24 | − | 20 ... 24 |
| No. 5 light | − | 5.0 ... 8.9 | 17 ... 22 |
| No. 5 | − | 9.0 ... 14.9 | 14 ... 18 |
| No. 6 | − | 15 ... 50 | 8 ... 15 |
Examples for viscosity readings of different No. 6 fuel oils obtained by SVM™. This oil type is usually also measured at 50 °C.
| No. 6 Fuel Oils | Kin. Viscosity [mm²/s] at 50°C | Kin. Viscosity [mm²/s] at 100°C |
|---|---|---|
| 1109 | 317.2 | 30.27 |
| 1309 | 420.9 | 37.90 |
| 1301 | 224.1 | 26.43 |
| 1101 | 363.2 | 34.01 |
| 1009 | 300.0 | 30.08 |
ASTM D396
Measurement with SVM™
| Reference | ASTM D396, measurement with SVM™ |
|---|---|
| Kin. vis. | yes |
| Dyn. vis. | no |
| Density | yes |
| Multiple temperatures | yes |
| Related | Heavy oil, heavy fuel, residual fuel oil, HFO, RFO, heating oil, viscosity, ASTM D396 |