How to identify and classify different types of bitumen?
The penetration test of bitumen quantifies the hardness or softness of bitumen by measuring the depth of penetration of standard loaded needle in five seconds while maintaining bitumen sample temperature at 25 °C. The more viscous the bitumen, the less distance needle is able to penetrate. Hence, the penetration value for viscous bitumen is less.
For instance, if the needle penetrates between 6 and 7 mm in 5 seconds, we will have 60/70 bitumen.
The penetration is measured to specify the bitumen type in accordance with the climatic conditions of the area of bitumen consumption.
This penetration depth is empirically (albeit only roughly) correlated with asphalt binder performance. Therefore, asphalt binders with high penetration numbers (called “soft”) are used for cold climates (like 85/100) while asphalt binders with low penetration numbers (called “hard”) are used for warm climates (like 40/50).
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Production of various types of bitumen, including 40/50, 60/70, 80/100, 200/300, VG10, VG20, VG30, VG40, AH70, AC20, and other grades upon customer request.
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Delivery of products in various packaging types according to customer needs (including 180 kg drums, 200 kg drums, flexi tanks, jumbo bags, bulk, etc.)
In the early 1960s, a new classification was presented, which was more scientific than the empirical classification of the penetration degree. Grading of bitumen based on viscosity is done based on viscosity at temperatures of 60 (average temperature of the road surface during sunlight) and 135 (average temperature of bitumen when mixing asphalt) degrees Celsius. Usually, in tropical regions, bitumen with a higher viscosity grade (for example, VG40) is used, and in cooler regions, bitumen with a lower viscosity grade (for example, VG10) is used.
PG system is a method of measuring asphalt binder performance; In a Super-pave grading system, binders are classified according to their performance in extreme hot and cold temperatures and called Performance Grade Bitumen.
The main purpose of grading and selecting asphalt binder using the Performance Grade system is to ensure that the binder has the appropriate properties for environmental conditions in the field.
Performance Grade asphalt binders are selected to meet expected climatic conditions as well as traffic speed and volume adjustments.
Therefore, the Performance Grade system uses a common set of tests to measure the physical properties of the binder that can be directly related to the field performance of the pavement at its service temperatures by engineering principles.
Cutback bitumen is a mixture of bitumen and a suitable solvent (e.g. kerosene or gasoline). The type and quality of Cutback bitumen depends on the quality of the original pure bitumen, the type of solvent and the amount of solvent. This bitumen is liquid at room temperature or liquefied with a little heat.
Cutback bitumen is used in road construction for surface coatings, infiltration, cold factory asphalt or on-site mixes.
Cutback bitumen are divided into the following 3 groups according to the setting speed and the type of solvent:
– Rapid Curing Bitumen (RC):
Due to the high rate of evaporation of gasoline, the bitumen dissolved in gasoline hardens faster. This bitumen is called rapid curing bitumen.
– Medium Curing Bitumen (MC):
Bitumen dissolved in kerosene are called medium curing bitumen, which has a slower and longer evaporation rate than gasoline.
– Slow Curing Bitumen (SC):
Graves that are dissolved in gas oil or furnace oil are called slow curing bitumen.