ASTM D2878 Test Method for Estimating Apparent Vapor Pressures and Molecular Weights of Lubricating Oils
11. Report
11.1 If the results are obtained in accordance with 9.1, 9.2, 9.3, and 9.5, and calculated by Eq 3, they shall be reported as "Apparent Vapor Pressure = _ _ torr at _ _ °C (_ _ °F), and Molecular Weight = _ _ ".
11.2 If the results are obtained in accordance with 9.1, 9.2, 9.3, and 9.5, and calculated by Eq 4, Eq 5, or Eq 6, they shall be reported as "Apparent Vapor Pressure = _ _ torr at _ _ °C (_ _ °F), and Molecular Weight = _ _, calculated as polyol ester", "...diester", or "...petroleum", as appropriate.
11.3 If the results are obtained as indicated in 9.4 or Note 5, they shall be reported as "Apparent Vapor Pressure = _ _ torr at_ _ °C (_ _ °F) and 0 to _ _ percent evaporated". The molecular weight shall be reported only if the test was conducted at 477K (400°F) or a separate test at this temperature was made.
12. Precision
12.1 No independent precision statement can be issued at this time. However, the statement in Test Method D972 may be used as a guide. Applying the exponent 1.164 from Coburn's paper to the Test Method D972 statement results in the following criteria for apparent vapor pressure results:
12.1.1 Repeatability - The difference between two test 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:
6%
12.1.2 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, in the normal and correct operation of the test method, exceed the following values only in one case in twenty:
23 %
12.2 Similarly, from Test Method D2595, for use with that apparatus:
12.2.1 Repeatability - The difference between two test 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:
23 %
12.2.2 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, in the normal and correct operation of the test method, exceed the following values only in one case in twenty:
35 %
12.3 Bias - No statement is made on bias for this test method since the results cannot be compared to an accepted reference material.
13. Keywords
13.1 lubricating oils; molecular weight; vapor pressure
