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Bitumen is a black or dark-colored (solid, semi-solid, viscous) material that can be found in different forms, such as natural bitumen and bitumen derived from crude oil, which is referred to as petroleum bitumen.

Actually, it is a semi-solid hydrocarbon product produced by removing the lighter fractions (such as liquid petroleum gas, petrol and diesel) from heavy crude oil during the refining process. As such, it is correctly known as refined bitumen.

In North America, bitumen is commonly known as "asphalt cement" or "asphalt". Bitumen occurs in nature in several forms: hard one-easily crumbled bitumen in rock asphalt and softer, more viscous material which is present in asphalt lakes. Another way in which bitumen can be obtained is through petroleum processing in this manner bitumen is essentially the residue yielded through a distillation process of petroleum. Although bitumen can be found in natural form. Naturally-occurring bitumen, can be divided to rock asphalt and lake asphalt. It occurs only in small quantities and its properties are quite different from refined bitumen.

Pure bitumen is the refined product which is directly produced by vacuum distillation. These kinds of bitumen could be exposed to Aeration. Penetration, viscosity grade and performance grade are pure bitumen.


1Visio   

 While, two methods used mostly to modify bitumen properties are emulsification with water and dilution with hydrocarbon solvent enabling the bitumen to be applied cold, up to about 80°C for emulsions or up to .about 150°C for cutbacks, depending on the dilution and solvent used

 The legend of figure:

 

1) PG X-Y
X  is maximum   tolerable Temperature of bitumen
Y is minimum  tolerable Temperature of bitumen which is minus
2) PMB(E)-X, PMB(P)-X
X is softening point
3) NRMB X
X is softening point 
4) CRMB X
X is softening point
5) AR X and AC X
X *100=viscosity at 60 °C
6) Cut Back types :
1: low viscosity
2: hard asphalt
h : high viscosity
K1X: k type use for tack coating (tack coating is a method of Applying 
one layer of bitumen emulsion between surface below the road and  the
 road surface which results to stick two layers and avoids slipping  on
 each other. Cationic Rapid Set (CRS) or Cationic Slow Set (CSS)  type
of bitumen emulsion are used for this application.)
 X is the percent of bitumen
 HF : thick bitumen
  Q in naming means that it mixed with cement
7) SCX
   X is minimum viscosity

Applications; 90 percent of the bitumen is used in the construction and maintenance of roads meanwhile 10 percent of the bitumen is used in the roofing and canals and tunnels, pipe coating.


Last Update : Aug 7, 2019 13:12