Viscosity Grade bitumen is manufactured and graded differently from other types of bitumen. This grade of bitumen has been introduced to the industry in order to make the behaviour of bitumen more predictable at various temperatures, particularly higher ones.
All Bitumen VG grades are produced by the oxidation of the vacuum bottom. In this process, it is the high quality of raw materials that signals the better performance of VG bitumen, in the time of application.
In addition, viscosity grade bitumen is tested and classified differently from other types of bitumen. After production, we test the VGs by a viscometer to classify them according to their level of viscosity in three various temperatures. Find out more about viscosity testing here. This testing system results in the classification of bituminous products to four VG grades including VG10 Bitumen, VG20 Bitumen, VG30 Bitumen, and VG40 Bitumen. The higher the number, the harder the bitumen in the viscosity grading system.
Viscosity grade bitumen is one of the most widely used grades of bitumen in the world. In comparison to penetration grade bitumen, this type of bitumen is easier to handle (both mixing and compaction) and its resistance to rutting is more predictable.
Viscosity Grade (VG-10, VG-20, VG-30, VG-40)
CHARACTERISTICS |
VG-10 |
VG-30 |
VG-40 |
Absolute Viscosity 60°C, Poises, min |
800 |
2400 |
3200 |
Kinematic Viscosity, 135°C, CST, min |
250 |
350 |
400 |
Flash point, C, min |
220 |
220 |
220 |
Solubility in trichloroethylene, %, min |
99 |
99 |
99 |
Penetration at 25°C |
80-100 |
50-70 |
40-60 |
Softening point, C, min |
40 |
47 |
25 |
Tests on residue from thin film over test / RTFOT |
|||
Viscosity ratio at 60°C, max |
4 |
4 |
4 |
Ductility at 25°C, cm, min, after thin film over test |
75 |
40 |
25 |
What is the standard application for each grade of viscosity bitumen?
The application of viscosity grade bitumen is extremely popular when it comes to road construction, paving sidewalks, spraying, and surface dressing. Viscosity bitumen, which is the most widely used in hot asphalt construction, has thermoplastic properties, a property that keeps this material hard and stiff in cold weather and soft in hot temperature.
This feature makes the combination of viscosity bitumen with other materials more durable for road construction at a specific temperature. For applying viscosity grade bitumen, it is necessary to choose the appropriate grade.
Two main factors that help us decide which grade is suitable, are traffic conditions and climate. For example, bitumen with a viscosity value of 10 or 20 suits repairing and pavements. Or VG30 and VG40 are recommended for road construction where extra heavy traffic is expected.
In what follows, we present a comprehensive description of viscosity grade bitumen application for each grade, in addition to their properties and specifications.