Owner's manual

of less than that, then pour 200 ml of alcohol on to the specimen. Add approximately
700 ml of methylene chloride, stir occasionally for approximately five minutes or until all
asphalt is visually in solution.
TABLE 1: SIZE OF TEST SPECIMEN
NOMINAL MAXIMUM
SIEVE SIZE
APPROXIMATE MINIMUM
WEIGHT OF SPECIMEN (GM)
No. 4 500
3/8" 1000
½" 1500
¾" 2000
1" 3000
1½" 4000
4. Method A
PROCEDURE
4.1 Place a dry tare filter on the vacuum extractor and tighten the wing nuts finger tight.
(care must be taken to see that the filter is centered.)
4.2 Start the vacuum pump and decant the solvent from the prepared specimen into
the extractor then gently pour the specimen into the vacuum extractor, being sure
to wash the beaker completely clean with the wash bottle. Gently distribute the
specimen evenly over the filter paper with spatula.
4.3 When the solvent added under section 4.2 has been vacuumed off, turn off the
vacuum pump and open the vacuum valve, then pour enough methylene chloride,
approximately 700 ml, to cover the specimen stir gently with spatula until all
aggregate has been moved slightly then vacuum off the solvent. This procedure is
repeated until the solvent in the inspection tube is a light straw color. (Note: solvent
may be slowed for observation by partially opening vacuum valve and reducing
vacuum to a few inches.)
4.4 Let the vacuum pump run for a few minutes after the last wash, to aid in drying
the specimen. Scrape the aggregate away from the side of the funnel ring toward
the center of the filter to avoid loss when the ring is removed. Remove the ring
and brush the clinging aggregate into the drying pan. Then pick up the filter
paper and aggregate by holding the filter paper on opposite sides and raising it
straight up. Place the specimen in the tare pan and brush the clinging aggregate
from the filter into the pan. The aggregate shall then be dried on the hot plate,
bringing it to a temperature of about 130°F in ten minutes. Stir occasionally. DO
NOT LET SPECIMEN REACH OVER 140°F. When visually dry, sniff cautiously for
odor, continue drying and stirring until odor free. Weigh filter and aggregate in pan
and record. Let stand five minutes and weigh again. If weight loss is less than 0.01
percent of the specimen weight, the aggregate shall be considered dry. If not dry let
stand, stirring occasionally until weight loss is less than 0.01 percent in five minutes.
Then weigh and record. Subtract the weight of the filter and pan to determine the
weight of the extracted aggregate.