Viscosity grade bitumen:

in four different types including VG10, VG20, VG30 and VG40 is the most widely used bitumen in India, which has been replaced by bitumen penetration grade according to the Indian Standard (IS:73).
This kind of bitumen is more reliable than others due to its advantages and properties.
In the following, we will tell you more about the applications, descriptions and specification of each grades, and you will find the best VG bitumen that you need.

VG 10 Bitumen

VG 20 Bitumen

VG 30 Bitumen

VG 40 Bitumen

What is the difference between penetration grade bitumen and viscosity grade bitumen?

The difference between penetration grade bitumen and viscosity grade bitumen is that the penetration grade classification is based on the Penetration value in 25 ◦C, while VG system is based on Viscosity value in both 60 ◦C and 135 ◦C that shows it is suitable for both low and high temperature so the bitumen behavior in different thermal conditions can be predicted well.

Classification of Viscosity Grade Bitumen
Viscosity test on bitumen results the classification of bitumen in a range of grades, including VG10 Bitumen, VG20 Bitumen, VG30 Bitumen, and VG40 Bitumen.
The higher the number, the harder the bitumen in the viscosity grading system.
To know more about VG’s specification and comparison of the properties of grades, see the table at the end of the article.

Viscosity grade Standards
Viscosity Grade bitumen is determined by IS 73, ASTM and AASHTO.
According to the IS, grading of Bitumen is changed from penetration grade to viscosity grade in 2006.
Read the article to understand the viscosity grade bitumen definition, applications and specifications.Viscosity grade Standards
Viscosity Grade bitumen is determined by IS 73, ASTM and AASHTO.
According to the IS, grading of Bitumen is changed from penetration grade to viscosity grade in 2006.
Read the article to understand the viscosity grade bitumen definition, applications and specifications.

Application of viscosity grade bitumen
Generally, each of these viscosity grade bitumen has different application according to the two important factors such as climate and traffic conditions.
The important use of VG bitumen is due to the existence of two important properties of this material which are water impermeability and high adhesion.
Today, more than 250 different applications for VG bitumen have been considered that it seems to be impossible to replace them with other materials.
In the table you can see different applications and properties of VG bitumen.

Application of viscosity grade bitumen:

Grade	Viscosity Range at 60°C (Absolute Viscosity)	Typical Applications
VG-10 Bitumen	800-1200	Recommended for road construction in cold regions
		Ideal for spraying
		Used in production of bitumen emulsion
VG-20 Bitumen	1600-2400	Used in cold regions for road construction
VG-30 Bitumen	2400-3600	Maximizes asphalt performance in   hot regions
		A more reliable choice than  bitumen pen 60/70
VG-40 Bitumen	3200-4000	Works in areas with high traffic loads
		Well suited for road construction in hot weather

Advantages of viscosity grade bitumen:

Nowadays, VG bitumen is used instead of penetration bitumen, because it is tested more carefully in two phases by experts. First, the penetration of bitumen is measured at 25 ◦C that is the average temperature, but the results of this test is not reliable in the hot weather, so they measure the viscosity of bitumen at 60 ◦C and 135 ◦C. These tests tell us that:

1- VG bitumen is suitable for a wide range of temperature; 25 ◦C for fatigue cracking and 135 ◦C for construction , also temperature susceptibility can be determined
2- Less number of tests save time and costs; according to IS it has only 7 tests while penetration has 14 tests.
3- Longer durability: the pavement made from VG Bitumen will have better performance, because Viscosity value at 135 C gives sufficient idea about mixing and compaction temperature and as a result pavement life is improved.
4- Any two samples of same VG bitumen would give similar rutting performance in hot summer unlike the penetration grade
5- Minimum specified kinematic viscosity value at 135 C helps to minimize the potential of tender mixes during construction
6- VG bitumen is suitable for areas with high traffic loads


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.