ISO VG Viscosity Classification for Industrial Liquid Lubricants
The viscosity of nonautomotive engine and gear oils are specified according to ISO VG (International Organization for Standardization – Viscosity Grade). There are 18 viscosity grades normalized ranging from 2 mm2/s (viscosity of diesel fuel) to 1500 mm2/s (very thick cylinder oils). Designed to determine the so-called “midpoint viscosity” at +40°C.
ISO Viscosity grades
| ISO viscosity grades | Kinematic viscosity, mm2/s midpoint | Kinematic viscosity, mm2/s at +40°C | |
| min. | max. | ||
| 2 | 2,2 | 1,98 | 2,42 |
| 3 | 3,2 | 2,88 | 3,52 |
| 5 | 4,6 | 4,14 | 5,06 |
| 7 | 6,8 | 6,12 | 7,48 |
| 10 | 10 | 9,00 | 11,0 |
| 15 | 15 | 13,5 | 16,5 |
| 22 | 22 | 19,8 | 24,2 |
| 32 | 32 | 28,8 | 35,2 |
| 46 | 46 | 41,4 | 50,6 |
| 68 | 68 | 61,2 | 74,8 |
| 100 | 100 | 90,0 | 110 |
| 150 | 150 | 135 | 165 |
| 220 | 220 | 198 | 242 |
| 320 | 320 | 288 | 352 |
| 460 | 460 | 414 | 506 |
| 680 | 680 | 612 | 748 |
| 1000 | 1000 | 900 | 1100 |
| 1500 | 1500 | 1350 | 1650 |
Comparison of ISO And SAE Viscosity Classes
| ISO viscosity grades of industrial oils | SAE grades of engine oils | SAE grades of oils for manual transmissions |
| 2 | ||
| 3 | ||
| 5 | 0W | |
| 7 | ||
| 10 | ||
| 15 | 5W | 70W |
| 22 | 10W | 75W |
| 32 | ||
| 46 | 15W, 20W
25W, 20 |
80W |
| 68 | ||
| 100 | 30 | 85W |
| 150 | 40 | 90 |
| 220 | 50 | |
| 320 | 140 | |
| 460 | 250 | |
| 680 | ||
| 1000 | ||
| 1500 |