Penetration grade bitumen is a straight run bitumen specified by the penetration and softening point test. Penetration bituminous asphalt soften at high temperature and harden at low temperature due to Having thermoplastic property. Penetration grade asphalt is manufactured by vacuum distillation of crude oil. The most common grade is bitumen 60/70 which can be used for many applications. The penetration bituminous asphalt with high penetration numbers which are soft, mostly used in cold weather conditions and hard bituminous asphalt (low penetration number) can be used for warm weather condition.
The bitumen penetration grade 60/70 is semi hard penetration grade, with penetration between 60 and 70 usually used as paving grade bitumen.Which is moastly used in road construction, asphalt pavement and manufacter of hot-mix asphalt.
Specification of penetration bitumen 60-70
Test method
Unit
Specification
Specific gravity @ 25°c
ASTM D70
Kg/cm3
1.01/1.06
Penetration @ 25°c
ASTM D5
mm/10
60/70
Softening point °c
ASTM D36
°C
49/56
Ductility @25 °c
ASTM D113
cm
100 min
Loss on heating(wt.) %
ASTM D6
wt. %
0.2 max
Drop in penetration after heating %
ASTM D5-D6
%
20 max
Flash point °c
ASTM D92
232 min
Solubility is CS2(wt) %
ASTM D4
99 min
Spot test
A.A.S.H.O.T102
negative