ASTM D3245 Test Method for Pumpability of Industrial Fuel Oils
8. Procedure
8.1 Fill the oil cup with the sample at a temperature not exceeding 82°C (180°F) to a depth of 60 mm (2 1/4 in.). Gently slide the oil container back onto the viscometer and lock in position with the cap. Place the assembly in its working position in the water bath maintained at 82 +/- 1°C. After 5 min, remove excess oil above the level of the top of the outer cylinder. A bent pipet is suitable for this purpose. Further slight expansion of the oil should be ignored.
8.1.1 The oil may be heated to a temperature not exceeding 82°C to make it pour easily into the viscometer. If a hot plate is used to warm the sample, care must be exercised to continuously stir the sample and ensure that the surface temperature does not exceed 82°C (180°F).
8.2 After 20 min, transfer the viscometer assembly to the bath set at the predetermined chilling temperature (see Table 1).
8.3 After 15 min, start the viscometer with the gear change lever at Speed 3.
8.4 After a further 5 min, cool the bath at 0.5°C/min such that at any time the temperature does not differ from the required temperature by more than +/-0.5°C.
8.5 Every 2.5 min, note the scale deflection to the nearest 0.5 division and bath temperature to the nearest 0.1°C. Convert the scale deflection to viscosity in poise by multiplying by the appropriate viscometer factor (see Annex A1). Record viscosities to the nearest 0.01 Pa•s (0.1 P).
8.6 Continue until the full-scale deflection of the instrument is reached or until the bath temperature has fallen to 2°C.
8.6.1 If it is desired to obtain 2.5 Pa•s (25 P) temperatures below 4°C, cooling shall be maintained at the same rate until the full-scale deflection is reached. An appropriate cooling bath will be required in place of the water bath (6.5).
8.7 Plot the curve of viscosity versus bath temperature on linear scales and read off the bath temperatures corresponding to viscosities of 0.6 Pa•s (6 P) and 2.5 Pa•s (25 P).
8.8 If the 0.6 Pa•s (6 P) temperature is above the predetermined intermediate chilling temperature, repeat the whole test on a fresh sample using the intermediate chilling temperature for the next higher viscosity level. If it is known from previous experience that the chilling temperature for the higher viscosity level will be required, it is not necessary to carry out the test at the lower level.
8.9 To allow for the difference between the bath temperature and the oil temperature, add 2°C to the bath temperatures corresponding to 0.6 and 2.5 Pa•s (6 and 25 P). These adjusted temperatures are the 0.6 and 2.5 Pa•s (6 and 25 P) temperatures for the oil.
