ASTM D6 standard test method for loss on heating of oil and asphaltic compounds
8. Procedure
8.1 Place 50.0 more or less 0.5 g of the sample of the water-free material to be tested in a tared container conforming to the requirements of 5.3, and weigh to the nearest 0.01 g. If the material has been heated to facilitate transfer, cool the sample to room temperature before making this initial weighing. Bring the oven to a temperature of 163°C (325°F), and place the container with the weighed sample on and near the circumference of the circular shelf, in one of the recesses if the recommended shelf is used. Close the oven and rotate the shelf during the entire test at a rate of 5 to 6 rpm. Maintain the temperature at 163 more or less 1°C (325 more or less 1.8°F) for 5 h after the sample has been introduced and the oven has again reached that temperature. The 5-h period shall start when the temperature reaches 162°C (324°F), and in no case shall the total time that a sample is in the oven be more than 5 h and 15 min. At the conclusion of the heating period, remove the sample from the oven, cool to room temperature, weigh to the nearest 0.01 g, and calculate the loss due to heating.
8.2 Determine temperatures by means of the specified thermometer, which shall be supported from the shaft of the circular shelf in a vertical position approximately 19 mm (0.75 in.) inside the periphery of the shelf, and with the bottom of the thermometer bulb 6 mm (0.25 in.) above the shelf.
NOTE 3 - If additional periods of heating are desired, it is recommended that they be made in successive increments of 5 h each.
NOTE 4 - When it is required that the penetration or other characteristics of the sample after heating be determined, the residue should be melted in the container at the lowest possible temperature and thoroughly mixed by stirring, taking care to avoid incorporating air bubbles in the material. For the penetration test, the well-mixed residue shall be brought to standard temperature and tested as prescribed in Test Method D5. For other tests, the well-mixed residue should be tested according to standard conditions as required by the test procedure involved.
