Bitumen 60/70

Bitumen 60/70.

Bitumen 60/70 is the term often given to untreated asphalt from the vacuum distillation of crude and the extract from the de-asphalting unit. This is before the stream has been treated, with cut backs or by air blowing to make the various asphalt product grades. In bitumen production the heavy vacuum residue, which is the basis for most bitumen grades, may be air blown. This becomes necessary to meet certain bitumen grades. The air used in this air blowing procedure must be perfectly dry to avoid an explosion in the reactor vessel.

This grade of Bitumen is mainly used in the manufacture of hot mix asphalt for bases and wearing courses.

Penetration Grade bitumens are specified by the penetration and softening point test. Designation is by penetration range only. The penetration grade bitumens have a thermoplastic property which causes the material to soften at high temperatures and to harden at lower temperatures. This unique temperature/viscosity relationship is important when determining the performance parameters such as the adhesion, rheology, durability and application temperatures of bitumen.