ASTM D6594 method for evaluation of corrosiveness of diesel engine oil at 135 °C
9. Procedure
9.1 Place the specimen hanger onto the air tube and hang test specimens on their respective hooks.

9.1.1 Arrange the specimens on the hanger in the sequence: lead, copper, tin, and phosphor bronze.

9.2 Insert the air tube with the attached specimens into the sample tube so that the air tube rests on the bottom of the sample tube.

9.3 Place the sample tube top on the sample tube.

9.4 Weigh the air tube, sample tube, and contents together within 0.1 g.

9.5 Add 100 +/- 1 mL of test oil volumetrically to the sample tube by syringe. Reweigh the air tube, sample tube, and contents together to within 0.1 g, and determine the weight of the oil added.

9.6 Assemble the sample tube and condenser and mount the assembly so that 30 +/- 5 cm of the sample tube is submerged in the bath with the test oil temperature set at 135 +/- 0.5°C.

9.7 Start the flow of the cooling water through the condenser jacket.

9.8 To begin testing, connect the source of clean, dry air (5 +/- 0.5 L/h) to the air tube and allow the air to flow for 168 h. House air with pre-drying or bottle reagent grade air should be used. Use a calibrated flow meter in setting airflow rates.

9.9 End of Test - After 168 h at 135°C, shut off the airflow and disassemble.

9.9.1 Remove air supply and disconnect condenser.

9.9.2 Remove sample tube from the bath, allow it to cool at least for 15 min, and wipe off the outside of the tube with a cloth dampened with naphtha.

9.9.3 Make the following measurements: Re-weigh the air tube, sample tube, and contents to within 0.1 g, determine weight of the oil sample remaining, and compute the percentage of weight loss resulting from evaporation of oil (see 10.5.1). If the evaporation loss is greater than 8 % leakage is present. Correct the leak, and repeat the determination, using a fresh oil sample and new specimens.

10. Test Results
10.1 Remove the air tube with the attached specimens from the sample tube. Do not touch the specimens with hands. Retain the sample tube and test oil for further examination.

10.2 Using forceps or gloves, wash the copper specimen in tetrahydrofuran, and discard the other specimens.

10.3 Rate the copper specimen for tarnish according to the Strip Examination, Interpretation, and Report sections of Test Method D130.

10.4 Immediately after calibration of the ICP-AES instrument (as specified in Test Method D5185), use Test Method D5185 to determine the concentration of copper, lead, and tin in both the new and used oil.

10.5 Calculations:
10.5.1 Evaporation Loss:
L = [(W1 - W2)/W3] x 100
where:
L = percent evaporation loss,
W1 = initial weight of air tube, sample tube and contents, including test oil,
W2 = final weight of air tube, sample tube and contents, including test oil, and
W3 = initial weight of test oil.

10.5.2 Change in metal concentration in the used test oil:
ΔC = C2 - C1
where:
ΔC = change in metal concentration before and after test,
C1 = measurement of metal concentration in new test oil (as determined in 10.4), and
C2 = measurement of metal concentration in used test oil (as determined in 10.4).

11. Reference Oil Testing
11.1 Test a TMC-coded reference oil along with each batch of non-reference oil tests. Run the reference oil simultaneously with, and in the same bath as, the non-reference oils.

NOTE 1 - Annex A1 discusses the involvement of the ASTM TMC with respect to the reference test-monitoring program.

11.1.1 Prior to requiring a reference oil test, procure a supply of reference oils directly from the TMC. These oils have been formulated or selected to represent specific chemistry types, or performance levels, or both. Each reference oil sample is identified using a unique set of identification codes on the container labels. The coded reference samples provide for a blind reference-testing program to protect against the possibility of bias in the results.

11.1.1.1 The testing laboratory tacitly agrees to use the TMC reference oils exclusively in accordance with the TMC's published Policies for Use and Analysis of ASTM Reference Oils, and to run and report the reference oil test according to TMC guidelines.

NOTE 2 - Policies for the Use and Analysis of ASTM Reference Oils is available from the TMC.

11.1.2 Request a reference oil assignment from the TMC for this test method. The TMC will determine the specific reference oil to be tested by the laboratory. Assignments will be made by the unique identifying codes on the reference oil container labels. Provide the TMC with the bath identification number for the test.

11.1.3 Run the TMC reference oil test according to the test method and in the same manner as the non-reference oil test(s).

11.1.4 Reporting of Reference Oil Test Results - Report the results of all reference oil tests to the TMC according to the following directives:
11.1.4.1 Use the data reporting formats detailed in Annex A2 for reporting all TMC reference oil test data to the TMC. Report only the reference oil results to the TMC. Do not include any non-reference test data. Complete all of the required blank fields on the forms. The report forms and data dictionary are available on the ASTM Test Monitoring Center Web Page at http://www.astmtmc.cmu.edu/ or can be obtained in hardcopy format from the TMC.

11.1.4.2 Transmit reference test data to the TMC by electronic means or by telephone facsimile immediately upon completion of the test analysis. Include all of the reporting forms in the transmission.

NOTE 3 - Specific protocols for the electronic transmission of test data to the TMC are available from the TMC.

11.1.5 Evaluation of Reference Test Oil Results - Upon receipt of the transmitted TMC reference oil test results, the TMC will review the test for operational adherence to the published test method. If the test is found to be operationally valid, the reference oil results will be evaluated using acceptance criteria established by the governing surveillance panel. The reference oil acceptance criteria are subject to change at the discretion of the surveillance panel.

11.1.5.1 If the transmitted test is found to be both operationally valid and statistically acceptable, the testing laboratory will be notified of the acceptable status of the reference test. The uncoded TMC reference oil identification will also be disclosed to the testing laboratory.

11.1.5.2 In the event that a TMC reference oil test is found to be unacceptable, an explanation of the problem relating to the failure will be provided to the testing laboratory. If there is an obvious operational reason for the failed test, the problem shall be corrected before requesting another TMC reference oil assignment. If the reason for the failure is not obvious, all test-related equipment shall be re-checked for compliance to the test method and good laboratory practice. Following this re-check the TMC will assign another TMC reference oil for testing.

11.1.6 Status of Non-reference Oil Tests Relative to TMC Reference Oil Tests - The batch of non-reference tests is considered valid only if the results of the TMC reference oil test meet the predetermined acceptance specifications for the particular reference oil tested.