1、Designation: D7843 12Standard Test Method forMeasurement of Lubricant Generated Insoluble ColorBodies in In-Service Turbine Oils using Membrane PatchColorimetry1This standard is issued under the fixed designation D7843; the number immediately following the designation indicates the year oforiginal a
2、doption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method extracts insoluble contaminants from asample of in-s
3、ervice turbine oil onto a patch and the color ofthe membrane patch is analyzed by a spectrophotometer. Theresults are reported as a E value, within the CIE LAB scale.1.2 This test method is not appropriate for turbine oils withdyes.1.3 This standard does not purport to address all of thesafety conce
4、rns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D4057 Practice for Manual Sampling of Pe
5、troleum andPetroleum ProductsD4177 Practice for Automatic Sampling of Petroleum andPetroleum ProductsD4378 Practice for In-Service Monitoring of Mineral Tur-bine Oils for Steam and Gas TurbinesE177 Practice for Use of the Terms Precision and Bias inASTM Test MethodsE284 Terminology of AppearanceE308
6、 Practice for Computing the Colors of Objects by Usingthe CIE SystemE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method3. Terminology3.1 Definitions:3.1.1 CIELAB color scales, nCIE 1976 L*, a*, b*opponent-color scales, in which a* is positive in the reddi
7、rection and negative in the green direction; b* is positive inthe yellow direction and negative in the blue direction; and L*is positive in the lightness direction and negative in thedarkness direction. E3083.1.2 colorimetry, nthe science of color measurement.E2843.1.3 in-service oil, nlubricating o
8、il that is present in amachine that has been at operating temperature for at least onehour (for example, an engine, gearbox, transformer, or turbine).3.1.4 membrane color, na visual rating of particulate on afilter membrane against ASTM Color Standards.3.1.5 membrane filter, na porous article of clo
9、sely con-trolled pore size through which a liquid is passed to separatematter in suspension.3.2 Definitions of Terms Specific to This Standard:3.2.1 varnish, na thin, hard, lustrous, oil-insolubledeposit, composed primarily of organic residue, and mostreadily definable by color intensity. It is not
10、easily removed bywiping with a clean, dry, soft, lint-free wiping material and isresistant to saturated solvents. Its color may vary, but it usuallyappears in gray, brown, or amber hues.4. Summary of Test Method4.1 Insoluble deposits are extracted from an in-serviceturbine oil sample using a 47 mm,
11、0.45-micron membranenitro-cellulose patch. The color of the patch is then analyzedusing a spectrophotometer and the results are reported as a Evalue in the CIE LAB scale.5. Significance and Use5.1 This test can be a guide to end-users on the formation oflubricant-generated, insoluble deposits.5.2 Th
12、e results from this test are intended to be used as acondition monitoring trending tool as part of a comprehensiveprogram, as outlined in standards such as Practice D4378.1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products and Lubricants and is the direct responsib
13、ility of SubcommitteeD02.C0 on Turbine Oils.Current edition approved Dec. 1, 2012. Published January 2013. DOI: 10.1520/D7843-12.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume informati
14、on, refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States16. Apparatus6.1 Variations of apparatus, particularly with respect to filtermembranes and vacuum pump setting, can aff
15、ect the testresults significantly.6.2 When the user of this test method uses an alternatemembrane filter, it is incumbent upon them to establish that thealternate filter will give equal results.6.3 Required Apparatus:6.3.1 Membrane Filter, 47 mm nitro-cellulose, 0.45-m.6.3.2 Forceps, smooth-tip.6.3.
16、3 Borosilicate Filter Holder.6.3.4 Borosilicate Filtering Flask.6.3.5 Wash Bottle equipped with 0.22 micron membranes.6.3.6 Vacuum Source, capable of maintaining a vacuum of71 kPa 6 5 kPa.6.3.7 Graduated cylinder, 150200 mL.6.3.8 Beaker, 100250 mL.6.3.9 Petri dish.6.3.10 Spectrophotometer, with capa
17、bilities of analyzing astandard 15 mm target with a 0/45 measuring geometry, 10observer, 10 nm spectral intervals minimum resolution, thevisible spectral range of 400700 nm and CIELAB measuringindices.7. Reagents and Materials7.1 Petroleum Spirit (also known as petroleum ether or IPPetroleum Spirit
18、40/60) (WarningExtremely flammable.Harmful if inhaled. Vapors are easily ignited by electrostaticdischarges, causing flash fire.), having boiling range from 35 to60C.7.2 Coleman Camp FuelColeman Fuel is a complexmixture of light hydrocarbons (primarily aliphatic) producedby distillation of petroleum
19、. Carbon number range is C5 to C9,and contains less than 0.001% benzene.7.3 Purity of ReagentsReagent grade chemicals shall beused in all tests. Unless otherwise indicated, it is intended thatall reagents conform to the specifications of the Committee ofAnalytical Reagents of the American Chemical S
20、ociety wheresuch specifications are available. Other grades may be used,provided it is first ascertained that the reagent is of sufficientlyhigh purity to permit its use without lessening the accuracy ofthe determination.8. Sampling, Test Specimens, and Test Units8.1 Using either Practice D4057 (man
21、ual sampling) orPractice D4177 (automatic sampling), obtain a representativesample of at least 60 mL of the material to be tested. Thepreferred sample container is an amber or other dark coloredbottle to minimize potential UV reactions to the sample.Translucent or clear bottles can be used as long a
22、s the sampleis protected from UV exposure.8.2 The sample shall be heated to 6065C for 2325 h thenstored between 1525C, away from UV light for an incuba-tion period of 6876 hours. Samples that are analyzed prior tothis aging period may produce fewer color bodies on the patch;thus, producing a lower E
23、 value, and may lower the value oftrend analysis.NOTE 1Samples can be analyzed in longer or shorter intervals withagreement of the end-user. The level of deposit and as a consequence, thetest results may be affected by time duration chosen. It is sometimessuggested to additionally analyze the sample
24、 at multiple incubationperiods to fully understand the operating system.9. Procedure9.1 Preparation of Sample and Materials:9.1.1 Document the date and time at the beginning of thetest.9.1.2 Vigorously mix the sample for 15 s minimum toresuspend insolubles uniformly. Visually inspect the inside ofth
25、e bottle for evidence of material adherent to the surface of thebottle before sampling.NOTE 2If adherent material cannot be removed from bottle afterrepeated attempts to vigorously mix, include as comment in the reportingdocumentation.9.1.3 Transfer 50 mL 6 1 mL of sample into clean beaker orErlenme
26、yer flask.9.1.4 Add approximately 50 mL 6 1 mL of petroleum etherto beaker containing sample.9.1.5 Stir sample for approximately 30 s to ensure that acomplete solution (and complete mixing) is attained.9.1.6 Pour sample into filter funnel within 12 minutes ofinitial mixing.9.2 Filtration Process:9.2
27、.1 Using forceps, mount the filter on the center of thefilter holder.9.2.2 Mount and securely clamp the filter funnel to the filter.9.2.3 Apply a vacuum and ensure a vacuum of less than 76kPa is attained and held.9.2.4 Rinse the beaker twice with a minimum of 35 mL ofpetroleum ether and pour the rin
28、sing into the filter funnel.9.2.5 Permit the filtrate to completely flow through.9.2.6 Carefully, remove the clamp and funnel. Wash anyadhering insolubles from the funnel onto the membrane withpetroleum ether. Wash the membrane gently, particularly theedges, with petroleum ether from the wash bottle
29、.NOTE 3If any of the deposits fails to remain on (or falls off) the drymembrane the test must be repeated.9.2.7 Carefully release the vacuum.9.2.8 Remove the clamp and filter holder.9.2.9 Using forceps carefully remove the filter from thefilter holder and place into a clean dry petri-dish. To facili
30、tatehandling, the membrane filters might be rested on clean glassrods in the petri-dish.9.2.10 Dry the membrane by placing it in a low-level heatsource free of ignition sources for flammable vapors, or air dry(typically, 3 h) in a dust-free location. Dryness can be esti-mated by comparing the white
31、color of the outer edge of thetest membrane with a new membrane.9.3 Color Determination of the Membrane Patch:9.3.1 Standardize the instrument using a patch developedfrom clean solvent application of the method to establish thebackground color white.9.3.2 Follow the standardization procedure defined
32、 by theinstrument manufacturer.D7843 1229.3.3 Analyze the patch as recommended by the instrumentmanufacturer.9.3.4 Analyze the color of the patch in accordance with theequipment manufacturers instructions to produce a CIE LABvalue.10. Calculation of Results10.1 CIE 1976 L* a* b* Uniform Color Space
33、and Color-Difference EquationThis is an approximately uniform colorspace System defined by Practice E308. It is produced byplotting in rectangular coordinates the quantities L*, a*, b*,calculated as follows:L* 5 116*(YYn)132 16 (1)a* 5 500(XXn)132 YYn!13 (2)b* 5 200(YYn)132 ZZn!13 (3)XXn; YYn; ZZn.0
34、.01 (4)The tristimulus values Xn, Yn, Zndefine the color of thenormally white object-color stimulus, in this case the newmembrane patch. Under these conditions, Xn, Yn, and Znare thetristimulus values of the standard 10 observer, D65 illuminant.10.1.1 The total difference E*abbetween two colors each
35、given in terms of L*, a*, b* is calculated as follows:E*ab5 (L*)21(a*)21(b*)212(5)10.2 Reporting:10.2.1 Report the spectrophotometer CIE LAB E values toone decimal place.10.2.2 The incubation after heating shall be reported withthe E value.10.2.3 Note in the reporting documentation any deviationfrom
36、 this Standards methodology.11. Precision and Bias311.1 The precision of this test method is based on aninterlaboratory study conducted in 2011. Twelve laboratoriesparticipated in the study, testing seven different turbine oils,over three and five day periods. Every analyst was instructed toreport d
37、uplicate test results in this study. Practice E691 wasfollowed for the study design; the details are given in ASTMResearch Report RR:D02-1752.11.1.1 Repeatability limit (r)Two test results obtainedwithin one laboratory shall be judged not equivalent if theydiffer by more than the “r” value for that
38、material; “r” is theinterval representing the critical difference between two testresults for the same point, obtained by the same operator usingthe same equipment on the same day in the same laboratory.11.1.1.1 Repeatability limits are listed in Tables 1 and 2.11.1.2 Reproducibility limit (R)Two te
39、st results shall bejudged not equivalent if they differ by more than the “R” valuefor that material; “R” is the interval representing the criticaldifference between two test results for the same point, obtainedby different operators using different equipment in differentlaboratories.11.1.2.1 Reprodu
40、cibility limits are listed in Tables 1 and 2.11.1.3 The above terms (repeatability limit and reproduc-ibility limit) are used as specified in Practice E177.11.1.4 Any judgment in accordance with statements 9.1.1and 9.1.2 would have an approximate 95% probability of beingcorrect.3Supporting data have
41、 been filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR:D02-1752. ContactASTM CustomerService at serviceastm.org.TABLE 1 72-hours (3-Day)Material AverageRepeatabilityStandardDeviationReproducibilityStandardDeviationRepeatabilityLimitReproducibilityLimitxsrs
42、RrRSample 1 15.332 0.861 3.169 2.410 8.874Sample 2 7.409 0.910 2.830 2.547 7.925Sample 3 6.970 0.839 3.085 2.349 8.637Sample 4 3.472 0.468 2.047 1.309 5.732Sample 5 6.993 0.852 2.968 2.386 8.309Sample 6 34.258 3.656 11.556 10.236 32.357Sample 7 3.475 0.176 1.647 0.494 4.611TABLE 2 120-hours (5-Day)M
43、aterial AverageRepeatabilityStandardDeviationReproducibilityStandardDeviationRepeatabilityLimitReproducibilityLimitxsrsRrRSample 1 17.125 1.530 4.287 4.284 12.004Sample 2 7.618 0.715 2.919 2.003 8.174Sample 3 7.473 0.710 3.000 1.989 8.401Sample 4 3.584 0.519 1.872 1.452 5.242Sample 5 7.883 0.620 3.1
44、32 1.736 8.770Sample 6 38.615 4.889 12.300 13.690 34.439Sample 7 3.867 0.437 1.568 1.223 4.392D7843 12311.2 BiasAt the time of the study, there was no acceptedreference material suitable for determining the bias for this testmethod, therefore no statement on bias is being made.11.3 The precision sta
45、tement was determined through sta-tistical examination of 312 test results, from a total of twelvelaboratories, on seven turbine oils. The seven materials weredescribed as:Sample 1: 2011Sept-1, 3-day heating experiment for the 3-daywait after heating + 2011Sept-1, 5-day heating experiment for the5-d
46、ay wait after heatingSample 2: 2011Sept-2, 3-day heating experiment for the 3-daywait after heating + 2011Sept-2, 5-day heating experiment for the5-day wait after heatingSample 3: 2011Sept-3, 3-day heating experiment for the 3-daywait after heating + 2011Sept-3, 5-day heating experiment for the5-day
47、 wait after heatingSample 4: 2011Sept-4, 3-day heating experiment for the 3-daywait after heating + 2011Sept-4, 5-day heating experiment for the5-day wait after heatingSample 5: 2011Sept-5, 3-day heating experiment for the 3-daywait after heating + 2011Sept-5, 5-day heating experiment for the5-day w
48、ait after heatingSample 6: 2011Sept-6, 3-day heating experiment for the 3-daywait after heating + 2011Sept-6, 5-day heating experiment for the5-day wait after heatingSample 7: 2011Sept-7, 3-day heating experiment for the 3-daywait after heating + 2011Sept-7, 5-day heating experiment for the5-day wai
49、t after heating12. Keywords12.1 membrane patch colorimetry; turbine oil; varnishREFERENCES(1) Sasaki,A., et al., “Investigation of Oil Contamination by ColorimetricAnalysis” STLE/ASM Tribology Conference, San Francisco, CA,June 2001.(2) Livingstone, G., Thompson, B., and Okazaki, M., “Physical, Perfor-mance and Chemical Changes in Turbine Oils from Oxidation,”Journal of ASTM International Paper ID: JAI100465, January 2007.ASTM International takes no position respecting the validity of an
