ASTM D7216 Standard Test Method for Determining Automotive Engine Oil Compatibility with Typical Seal Elastomers

11. Report

11.1 Use the standardized report form set and data dictionary for reporting the test oil results.

NOTE 7 - Either download the actual report forms and data dictionary from the TMC website or obtain them in hardcopy format from the TMC.

11.2 Report the following information:

11.2.1 Test completion date.

11.2.2 Elastomer type and batch number.

11.2.3 Test oil identity.

11.2.4 Test temperature, °C.

11.2.5 Test duration, h.

11.2.6 Aging block or bath identification.

11.2.7 For each elastomer/oil combination, report:

11.2.7.1 Percent volume change, including the six individual values, the arithmetic mean and the standard deviation. Report volume change to two decimal places.

11.2.7.2 Durometer A hardness change, including the individual means for each of the six specimens, the arithmetic mean of these six values and the standard deviation. Report hardness change to the nearest whole Durometer A points, including the plus or minus sign.

11.2.7.3 Percent tensile strength change, including the six individual values, the arithmetic mean and the standard deviation. Report percent tensile strength change to one decimal place.

11.2.7.4 Percent ultimate elongation change, including the six individual values, the arithmetic mean and the standard deviation. Report percent ultimate elongation change to one decimal place.

11.3 Precision of Reported Units - Use Practice E 29 for rounding-off data. Use the rounding-off method to report data to the required precision.

11.4 Outliers - Report all data generated that was successfully measured. Do not apply any statistical measure for outlier screening. If any of the six individual values for any parameter were not measured successfully because of (1) grip slippage, (2) specimen breakage outside the test area, (3) a nick to the test specimen, or (4) an obvious material flaw (such as an air bubble), then record an asterisk (*) for that particular measurement and provide a description of the problem in the comment section of Form 7 of the test report. Compute the arithmetic mean and standard deviation using the remaining individual values. If more than two individual values for any of the four parameters need to be reported as an asterisk (*), the test is invalid.

12. Precision and Bias

12.1 Test precision is established on the basis of reference oil test results (for operationally valid tests) monitored by the ASTM Test Monitoring Center. The data are reviewed semi-annually by the Engine Oil Elastomer Compatibility Surveillance Panel. Contact the ASTM TMC for current industry data.

12.1.1 Tables 2-6 summarize reference oil intermediate precision and reproducibility of the test. The tabulated values are current as of August 2007. The Surveillance Panel updates these values as necessary.

12.1.2 Intermediate Precision Conditions - Conditions where test results are obtained with the same test method using the same test oil, with changing conditions such as operators, measuring equipment, test stands, test engines, and time.

NOTE 8 - Intermediate precision is the appropriate term for this test method rather than repeatability which defines more rigorous within-laboratory conditions.

12.1.2.1 Intermediate Precision Limit (i.p.) - The difference between two results obtained under intermediate precision conditions that in the long run, in the normal and correct conduct of the test method, exceed the values shown in Tables 2-6 in only one case in twenty. When only a single test result is available, the Intermediate Precision Limit can be used to calculate a range (test result +/- Intermediate Precision Limit) outside of which a second test result would be expected to fall about one time in twenty.

12.1.3 Reproducibility Conditions - Conditions where test results are obtained with the same test method using the same test oil in different laboratories with different operators using different equipment.

12.1.3.1 Reproducibility Limit (R) - The difference between two results obtained under reproducibility conditions that would, in the long run, in the normal and correct conduct of the test method, exceed the values in Tables 2-6 in only one case in twenty. When only a single test result is available, the Reproducibility Limit can be used to calculate a range (test result +/- Reproducibility Limit) outside of which a second test result would be expected to fall about one time in twenty.

12.1.4 Bias - No estimate of the bias for the procedure is possible because the performance results for an oil are determined only under the specific conditions of the test and no absolute standards exist.

13. Keywords

13.1 automotive engine oil; compatibility; elastomer; engine oil; immersion; seal(s)

11. Report

11.1 Use the standardized report form set and data dictionary for reporting the test oil results.

NOTE 7 - Either download the actual report forms and data dictionary from the TMC website or obtain them in hardcopy format from the TMC.

11.2 Report the following information:

11.2.1 Test completion date.

11.2.2 Elastomer type and batch number.

11.2.3 Test oil identity.

11.2.4 Test temperature, °C.

11.2.5 Test duration, h.

11.2.6 Aging block or bath identification.

11.2.7 For each elastomer/oil combination, report:

11.2.7.1 Percent volume change, including the six individual values, the arithmetic mean and the standard deviation. Report volume change to two decimal places.

11.2.7.2 Durometer A hardness change, including the individual means for each of the six specimens, the arithmetic mean of these six values and the standard deviation. Report hardness change to the nearest whole Durometer A points, including the plus or minus sign.

11.2.7.3 Percent tensile strength change, including the six individual values, the arithmetic mean and the standard deviation. Report percent tensile strength change to one decimal place.

11.2.7.4 Percent ultimate elongation change, including the six individual values, the arithmetic mean and the standard deviation. Report percent ultimate elongation change to one decimal place.

11.3 Precision of Reported Units - Use Practice E 29 for rounding-off data. Use the rounding-off method to report data to the required precision.

11.4 Outliers - Report all data generated that was successfully measured. Do not apply any statistical measure for outlier screening. If any of the six individual values for any parameter were not measured successfully because of (1) grip slippage, (2) specimen breakage outside the test area, (3) a nick to the test specimen, or (4) an obvious material flaw (such as an air bubble), then record an asterisk (*) for that particular measurement and provide a description of the problem in the comment section of Form 7 of the test report. Compute the arithmetic mean and standard deviation using the remaining individual values. If more than two individual values for any of the four parameters need to be reported as an asterisk (*), the test is invalid.

12. Precision and Bias

12.1 Test precision is established on the basis of reference oil test results (for operationally valid tests) monitored by the ASTM Test Monitoring Center. The data are reviewed semi-annually by the Engine Oil Elastomer Compatibility Surveillance Panel. Contact the ASTM TMC for current industry data.

12.1.1 Tables 2-6 summarize reference oil intermediate precision and reproducibility of the test. The tabulated values are current as of August 2007. The Surveillance Panel updates these values as necessary.

12.1.2 Intermediate Precision Conditions - Conditions where test results are obtained with the same test method using the same test oil, with changing conditions such as operators, measuring equipment, test stands, test engines, and time.

NOTE 8 - Intermediate precision is the appropriate term for this test method rather than repeatability which defines more rigorous within-laboratory conditions.

12.1.2.1 Intermediate Precision Limit (i.p.) - The difference between two results obtained under intermediate precision conditions that in the long run, in the normal and correct conduct of the test method, exceed the values shown in Tables 2-6 in only one case in twenty. When only a single test result is available, the Intermediate Precision Limit can be used to calculate a range (test result +/- Intermediate Precision Limit) outside of which a second test result would be expected to fall about one time in twenty.

12.1.3 Reproducibility Conditions - Conditions where test results are obtained with the same test method using the same test oil in different laboratories with different operators using different equipment.

12.1.3.1 Reproducibility Limit (R) - The difference between two results obtained under reproducibility conditions that would, in the long run, in the normal and correct conduct of the test method, exceed the values in Tables 2-6 in only one case in twenty. When only a single test result is available, the Reproducibility Limit can be used to calculate a range (test result +/- Reproducibility Limit) outside of which a second test result would be expected to fall about one time in twenty.

12.1.4 Bias - No estimate of the bias for the procedure is possible because the performance results for an oil are determined only under the specific conditions of the test and no absolute standards exist.

13. Keywords

13.1 automotive engine oil; compatibility; elastomer; engine oil; immersion; seal(s)