Lesson 6/Learning Event 4
TABLE 18. TEMPERATURE-VOLUME CONVERSION
DATA FOR BITUMINOUS MATERIALS
Refer to Step 10. Once the temperature factor is obtained from Table 18, it is multiplied by the
specific gravity of the asphalt cement. The result of this multiplication is a conversion factor.
The conversion factor (in this example, 0.9325) is then multiplied by the average weight of one
gallon of asphalt cement at 60F.
NOTE: The manufacturer has established 8.328 lbs per US gal. and
10.002 lbs per Imperial gal. as the average weight of asphalt cement at
60F. For the purposes of this calculation, these figures are considered
constant.
By multiplying the conversion factor 0.9325 by 8.328 lbs per US gallon, it is determined that the
asphalt being used will weigh 7.77 lbs per gal at mixing temperature.
c. Determine the pump setting (Table 19).
The METERING PUMP CAPACITY CHART (Table 19) lists the discharge rate of the metering
pump in lbs per rev for the given pump setting. The chart is based on asphalt weighing 7.85 lbs
per gallon at mixing temperature.
If in the above example, the calculated lbs per gallon had been 7.85, then the pump setting
required to deliver 9.3 lbs per rev may be obtained directly from the chart.
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