ASTM D4292 Test Method for Determination of Vibrated Bulk Density of Calcined Petroleum Coke
13. Report
13.1 Report the average of the two determinations to the nearest 0.001 g/cm3. The particle size range must be reported as part of the test results. For example, VBD (-30 + 50 sieve size) = 0.890 g/cm3.
14. Precision and Bias
14.1 Precision was determined by interlaboratory testing of calcined petroleum coke samples crushed and sized by the participants to pass through a 0.83-mm opening, (No. 20 sieve) and be retained on a 0.30-mm opening, (No. 50 sieve). Statistical information was calculated in accordance with methods outlined in RR:D02-1007.
NOTE 5 - Precision for vibrated bulk density on other ranges has not been determined.
14.2 Precision - The precision of this test method as determined by the statistical examination of interlaboratory test results is as follows.
14.2.1 Repeatability - The difference between successive results obtained by the same operator with the same apparatus under constant operating conditions on identical test material would, in the long run, in the normal and correct operation of the test method, exceed the following values only in one case in twenty.
Repeatability = 0.014 g/cm3
14.2.2 Reproducibility - The difference between two single and independent results obtained by different operators working in different laboratories on identical test material would, in the long run, exceed the following values only in one case in twenty.
Reproducibility = 0.046g/cm3
14.3 Bias - This test method is empirical and no statement as to bias is made.
15. Keywords
15.1 calcined petroleum coke; porosity; vibrated bulk density
