Page 51 - HIGHWAY ENGINEERING LABORATORY_FLIP BUILDER

3. 0 DETAILED PROCEDURE : VISCOSITY TEST AND FLASH & FIRE POINT

REFERENCE
WORK PROCESS DOCUMENT

For Bituminous material EXCEPT for Cutback Bitumen:
1. Clean all the parts of the cup and its accessories thoroughly and

allow them to dry.

2. Take the bitumen sample in a beaker and heat it to a
temperature of 75-100°C- above its approximate softening
point. Allow the bitumen to melt until it is converted
completely into a liquid state.

3. Fill the melted bitumen in the cup up to the filling mark indicated

on the cup.
4. Close the cup with the help of the lid. Ensure that the

locating devices of the cup and lid are properly engaged.

5. Place the cup on the stove.
6. Insert a thermometer and adjust the test flame to a size of a

bead of about 4 mm diameter. Control the rate of the
application of heat such that the temperature increases by 5-6
°C per minute as recorded from the thermometer.

7. Turn the stirrer at the rate of 60 rev/min.

8. Apply the first test flame when the temperature reaches
approximately 17 °C before the actual flash point. When test
flame is applied, discontinue the stirring.

9. Apply test flame at every reading of the temperature up to 104 °C
in the multiples of 1 °C. When the temperature exceeds 104 °C,

carry out the test at an interval of 2 °C.

10. Operate the device to apply the test flame by controlling shutter
and test flame burner in such a way that the flame is lowered in
0.5 seconds for. It remains in the lowered position for a second
and is raised quickly to the higher position.

11. Note down the temperature at which a distinct flash is observed in

the interior of the cup.

Higway Engineering Laboratory page 38