Viscosity indicates the resistance to flow due to its internal friction. The higher the viscosity, the lower the flow rate. The test is done to see if it is in the specified range. The test result is expressed in seconds for the flow of 60 cc of an emulsion sample through a 3.8 mm diameter orifice under specified conditions of the test.
- Saybolt Furol Viscometer
- stop the clock
- Clean the oil tube with a solvent such as benzene, and remove excess solvent from the gallery. Pass the entire contents through a 150 µm wire sieve before pouring it into the oil tube.
- After cleaning the tube, pour the amount of material to be tested into the tube, enough to moisten the entire surface of the tube. Let it out
- The plunger typically supplied with the viscometer shall never be used on equipment made as standards. Insert the cork stopper at least 6.0 mm and no more than 9.5 mm into the lower end of the air chamber at the bottom of the oil tube, taking care that the cork fits snugly enough for air to escape, as Tested is the absence of oil on the cork after retraction.
- If the test temperature is above room temperature, the material should be tested at 1.5 . do not overheat0C below the test temperature.
- Pour the material into the oil tube until it overflows into the gallery. Shake it well with the oil tube thermometer, taking care not to touch the outflow tube. Adjust the temperature of the bath until the temperature of the ingredients is stable.
- After achieving thermal equilibrium, no further adjustments will be made to the temperature of the bath. If the indicated bath temperature is +0.03 . test results will be rejected if0C.
- The temperature of the contents in the oil tube is +0.02 . after being fixed within0To the desired temperature for one minute with constant stirring, remove the oil tube thermometer and quickly remove excess liquid from the gallery through the extraction tube so that the level of material in the gallery is below the level of the oil tube. Suitable. Insert the tip of the evacuation tube at a point in the gallery.
- If the tip of the evacuation tube touches the overflow rim the test shall be resumed. In no case shall excess liquid be drained by rotating the evacuation tube around the gallery.
- Position the receiving flask so that the stream of liquid from the outlet tube hits the neck of the flask, taking care that the graduation mark on the receiving flask is not less than 10 cm from the bottom of the bath, not more than 13 cm . , Snap the cork out of its position and at the same time turn on the timer. When the bottom of the meniscus of the liquid reaches the mark on the neck of the receiving flask, stop the timer.
- Sabolt furol is the viscosity of the material at the temperature at which the test is carried out, with appropriate calibration correction, in a time determined by the prescribed procedure.
- Report results to the nearest 0.1 sec for viscosity values less than 200 sec and to the nearest full second for values of 200 sec or more.
The time in seconds determined by the procedure described above, with appropriate calibration correction, is the Sabolt furol viscosity of the material at the temperature at which the test is performed.
Report results to the nearest 0.1 s for viscosity values below 200 and to the nearest full second for values of 200 or greater.
IS 3117 – 1965
As per IS: 8887-2004, the acceptance limits of viscosity for different types of emulsions are as follows.
|type of emulsion||50. acceptance limit on0C|
|Rapid setting (RS-1)||20 – 100|
|Rapid setting (RS-2)||100 – 300|
|medium setting (ms)||50 – 400|
|slow setting (SS-1)||20 – 100|
|slow setting (SS-2)||30 – 150|