Viscosity grade bitumen is a petroleum grade bitumen derived from crude oil. This grade of bitumen is tested and classified differently from other types of bitumen. After production, refiners test the VGs by a viscometer to classify them according to their level of viscosity in various temperatures.
The viscosity test results in four VG grades of bitumen including VG10 Bitumen, VG20 Bitumen, VG30 Bitumen, and VG40 Bitumen. The higher the number, the harder the bitumen in the viscosity grading system.
In comparison to penetration grade bitumen, VG bitumen grades are more reliable and easier to handle (both mixing and compaction) and their resistance to temperature changes is more predictable.
Read the article to find out each VG bitumen grade’s description, applications, and specifications. Or use the below links to read the section you need.
Application of viscosity grade bitumen
Each grade of viscosity bitumen has its own properties and applications.
For making the most out of VG bitumen and maximizing its performance, it is necessary to read each grade’s specifications table and understand its properties very well.
Two main factors that help us decide are traffic conditions and climate. For example, VG10 bitumen suits repairing and spraying applications, but VG30 is recommended for road construction where extra heavy traffic is expected.
| Grade | Viscosity Range at 60°C (Absolute Viscosity) | Typical Applications ∞ |
| VG 10 | 800-1200 |
|
| VG 20 | 1600-2400 |
|
| VG 30 | 2400-3600 |
|
| VG 40 | 3200-4000 |
|
| Grade | Viscosity Range at 60°C (Absolute Viscosity) | Typical Applications ∞ |
| VG 10 | 800-1200 |
|
| VG 20 | 1600-2400 |
|
| VG 30 | 2400-3600 |
|
| VG 40 | 3200-4000 |
|
VG10 bitumen is the softest grade of viscosity bitumen. This type of bitumen is widely used for spraying applications and surface coating.
VG 10 bitumen means that your bitumen is also suitable for paving roads in a very cold and cold climate instead of the old 80/100 penetration grade. The air temperature that matches VG10 bitumen ranges from -100C to 250C. Due to the high temperatures in hot climatic zones, the application of VG10 cannot provide desirable rutting resistance.
This type of bitumen is also used to manufacture bitumen emulsions and modified bitumen products.
As a viscosity grade bitumen, VG10 has a better performance in cold weather. Refer to the table at the end of this page to see the bitumen VG 10 specification.
What are Advantages in the Application of Viscosity Grade 10 Bitumen?
It is suitable for temperature under 30°C,
Its absolute viscosity is 800,
It has a higher penetration value in comparison to VG30 and VG40.
VG-20 bitumen is a grade of viscosity bitumen used in cold climatic and high altitude regions. This grade of bitumen is suitable for road construction in regions with 30 to 37 °C average temperature. In North India, VG-20 is used for road construction in hot mix asphalt.
The standard penetration value of bitumen viscosity grade VG-20 is 60 mm at 25 °C. The absolute viscosity of VG-20 bitumen is 1600 to 2400 poise at 60 °C. For more information visit the specification table here.
This bitumen is primarily used for the construction of extra-heavy bitumen pavements that have to bear significant traffic loads. Bitumen VG30 is the most widely used type of bitumen in road construction, insulation, building construction industries, and also in the production of cutback bitumen.
VG 30 bitumen is a popular grade of bitumen in India. Indian importers prefer this type of bitumen because its performance in Indian road construction is proved. VG 30 grade bitumen is also used for plastic roads in India.
Because of having good thermal susceptibility, we use VG30 in areas that have a higher temperature. VG-30 bitumen is also suitable for use in hot and rainy weather conditions instead of bitumen penetration grades. The more viscose the bitumen, the fewer the chance of being affected by water.
30 In VG 30 bitumen means the range of viscosity [(100 +- 20) * 30] in terms of Poise. For VG 30 grade bitumen, the minimum viscosity at 60°c is calculated like this: 80 * 30 = 2400 Poise. The maximum viscosity is also calculated by this formula 120 * 30 = 3600 poise.
The difference between VG10 and VG-30 bitumen is in their viscosity level. Bitumen VG30 is more viscose than bitumen VG 10 and as a result, performs better in road construction in hot regions.
What are Advantages in the Application of Viscosity Grade 30 Bitumen?
It is suitable for temperature above 300C,
For a clayed soil, bitumen with higher viscosity is more suitable,
VG30 is more suitable for road construction in a rainy weather.
VG40 bitumen is used in areas in which high pressure comes from heavy traffic loads, such as intersections, near tolls booths, and truck parking lots.
Due to the high viscosity of this bitumen, it is more appropriate for improving resistance to shoving and other problems associated with higher temperatures and heavy traffic loads.
What are Advantages in the Application of Viscosity Grade 40 Bitumen?
It is suitable for a temperature above 40°C,
Its absolute viscosity is 3200,
It is a preferred type of bitumen when heavy traffic load is expected.
Viscosity Grade Bitumen Specifications Table
| CHARACTERISTICS∞ | VG-10 | VG-20 | VG-30 | VG-40 | |
| Absolute Viscosity 60°C, Poises, min | 800 | 1600 | 2400 | 3200 | |
| Kinematic Viscosity, 135°C, CST, min | 250 | 300 | 350 | 400 | |
| Flash point, C, min | 220 | 220 | 220 | 220 | |
| Solubility in trichloroethylene, %, min | 99 | 99 | 99 | 99 | |
| Penetration at 25°C | 80-100 | 60 | 50-70 | 40-60 | |
| Softening point, C, min | 40 | 45 | 47 | 25 | |
| Tests on residue from Infinity Galaxy thin film over test / RTFOT | |||||
| Viscosity ratio at 60°C, max | 4 | 40 | 4 | 4 | |
| Ductility at 25°C, cm, min, after thin film over test | 75 | 50 | 40 | 25 | |