ASTM D5862 Standard Test Method for Evaluation of Engine Oils in Two-Stroke Cycle Turbo-Supercharged 6V92TA Diesel Engine
12. Laboratory and Test Stand Calibration
12.1 Frequency of Calibration - To maintain test precision and avoid bias, engine test stand calibration is required at regular intervals. The frequency of calibration is dependent on the laboratories' previous calibration experience or at the discretion of the ASTM Test Monitoring Center. See 12.5.1.
12.2 Reference Oils - The reference oils used to calibrate 6V92TA test stands have been formulated or selected to represent specific chemical types or performance levels, or both. They are available from the TMC. The Test Monitoring Center will assign reference oils for calibration tests. These oils are supplied under code numbers (blind reference oils).
12.2.1 Reference oils and subsequent reblends that have been used in this test method are:
TMC 861 (REO 217), SAE 15W-40
TMC 862, SAE 30
12.3 Test Numbering - Each 6V92TA test shall be numbered to identify the test stand number, the test stand run number, engine number and number of runs made on engine. See 15.1 for test numbering protocol.
12.4 New Laboratories and New Test Stands:
12.4.1 A new stand is defined as a test dynamometer/cell and support hardware that has never been previously calibrated under this test procedure. On both new and existing stands the test engine is not part of the stand calibration.
12.4.2 A new laboratory shall have consecutive calibration test passes to be considered calibrated.
12.4.3 A laboratory not running a 6V92TA test for twelve months from the start of the last test is considered a new laboratory. Under special circumstances (that is, extended downtime due to industry-wide parts shortage or fuel outages) the TMC may extend the lapsed time requirement. Non-reference oil tests conducted during an extended time allowance shall be annotated on Form 15 (see Annex A5).
12.4.4 The TMC may schedule more frequent reference oil tests at their discretion.
12.5 Calibrated Laboratories and Test Stands:
12.5.1 A calibration test on a reference oil assigned by the TMC is required after no more than ten operationally valid non-reference oil tests starts or after six months from the start date of the last acceptable calibration test (whichever comes first).
12.6 Calibration Test Acceptance Bands:
12.6.1 Calibration test targets and acceptance bands are published every six months by the TMC. These acceptance bands, based on a 90 % confidence level, are calculated using reference oil tests completed during the previous six-month period or ten tests, whichever is greater. Calibration status of a test laboratory is based upon the calibration test acceptance bands in effect at the time of completion of the calibration test.
12.6.2 The specified test parameters for determination of the test acceptance bands are:
18.104.22.168 Cylinder liner, % area scuffing,
22.214.171.124 Fire ring face distress, demerits, and
126.96.36.199 Second and third ring average ring face distress, demerits.
12.7 Failing Calibration Tests:
12.7.1 Failure of a reference oil test to meet test acceptance bands can be indicative of a false alarm, testing stand, testing laboratory, or industry-related problem. When this occurs, the laboratory, in conjunction with the TMC, shall attempt to determine the problem source.
12.7.2 The TMC will decide, with input as needed from industry expertise (testing laboratories, test developer, ASTM Technical Guidance Committee, Surveillance Panel, and so forth), if the reason for any unacceptable blind reference oil test is isolated to one particular stand or related to other stands. If it is decided that the problem is isolated to an individual stand, calibrated testing on other stands can continue throughout the laboratory. Alternatively, if it is decided that more than one stand may be involved, the involved stands will not be considered calibrated until the problem is identified, corrected and an acceptable reference oil test completed in one of the involved stands.
12.7.3 If non-standard tests are conducted on the calibrated test stand, the stand may be required to be re-calibrated prior to running standard tests, at the discretion of the TMC.
12.8 Non-reference Oil Test Result Severity Adjustment:
12.8.1 Fixed non-reference oil test pass criteria are published in Specification D4485. Provision is made in this test procedure to adjust non-reference oil test results to compensate for test severity deviations from the original severity levels. Non-reference test adjustment factors represent the shift in the means of average liner scuffing, fire ring distress, and 2nd and 3rd ring face distress of Reference Oil 862 (and subsequent reblends) and are based on a moving average of the five most recent operationally valid tests on that oil.
12.8.2 Adjustment factors for non-reference tests are published semiannually by the TMC. Adjustment factors are applied (added) to individual test results based on the time period in which a 6V92TA test is completed. In the case of a single test, these adjusted results are compared to the fixed pass limits for a one-test program. In two-test or three-test programs, the adjusted test results are first averaged and then compared to the appropriate two-test or three-test fixed pass limits. Test results are recorded in the appropriate spaces on Form 20 (see Annex A5).
12.9 Reporting Reference Results:
12.9.1 Final Report Forms - For reference oil tests, the standalrdized report form and data dictionary for reporting the test results and for summarizing the operational data are required.
188.8.131.52 The report forms and data dictionary are available on the ASTM Test Monitoring Center or can be obtained in hardcopy format from the TMC.
12.9.2 Transmit the calibration test results by facsimile to the ASTM Test Monitoring Center immediately after completion of the test analysis using forms in the report forms, see Annex A5. Electronic data transfer is discussed in 15.4. Adhere to the variable formats (significant digits) listed in Annex A6 when reporting test results regardless of transfer medium.
12.9.3 Referee results should be reported to the TMC within ten working days of test completion.
12.9.4 The TMC will review all calibration test results to determine test acceptability. If the test is judged acceptable, the reference oil will be disclosed by the TMC. In the event the reference oil test is not acceptable, an explanation of the problem relating to the failure should be provided by the test laboratory. If the problem is not obvious, all test related equipment shall be rechecked. If no explanation of the problem is presented, it will be assumed the problem is laboratory related and another reference oil will be assigned.
12.9.5 One copy of the standard final test report with photographs, one copy of the daily and operational log sheets, and one copy of the rating work sheets for each 6V92TA reference oil test shall be forwarded as soon as possible to the following and shall be received within 30 days of test completion: ASTM Test Monitoring Center.
12.10 Analysis of Reference Oils - Do not submit reference oils to physical or chemical analyses, or both, for identification purposes prior to testing. Identifying the oils by analyses prior to testing could undermine the confidentiality required to operate an effective blind reference oil system. Therefore, reference oils are supplied with the explicit understanding that they will not be subjected to analyses other than those specified within this procedure (see 184.108.40.206) unless specifically authorized by the ASTM Test Monitoring Center. In such cases where analyses beyond the test procedure are authorized, written confirmation of the circumstances involved, the data obtained, and the name of the person authorizing the analysis shall be supplied to the ASTM Test Monitoring Center.