1、Designation: D7843 16D7843 18Standard 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 ofor
2、iginal adoption 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. Scope*1.1 This test method extracts insoluble contaminants from a samp
3、le of in-service turbine oil onto a patch and the color of themembrane patch is analyzed by a spectrophotometer. The results are reported as a E value, within the CIE LAB scale.1.2 This test method is not appropriate for turbine oils with dyes.1.3 The values stated in SI units are to be regarded as
4、standard. No other units of measurement are included in this standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety safety, health, and healthenvironmenta
5、l practices and determine theapplicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on Principles for the Development of International Standards, Guides
6、and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D4057 Practice for Manual Sampling of Petroleum and Petroleum ProductsD4177 Practice for Automatic Sampling of Petroleum and Petroleum ProductsD4378 Practi
7、ce for In-Service Monitoring of Mineral Turbine Oils for Steam, Gas, and Combined Cycle TurbinesE177 Practice for Use of the Terms Precision and Bias in ASTM Test MethodsE284 Terminology of AppearanceE308 Practice for Computing the Colors of Objects by Using the CIE SystemE691 Practice for Conductin
8、g an Interlaboratory Study to Determine 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 red direction andnegative in the green direction; b* is positive in the yellow direction and negat
9、ive in the blue direction; and L* is positive in thelightness direction and negative in the darkness direction. E3083.1.2 colorimetry, nthe science of color measurement. E2843.1.3 in-service oil, nlubricating oil that is present in a machine that has been at operating temperature for at least one ho
10、ur(for example, an engine, gearbox, transformer, or turbine).hour.3.1.4 membrane color, na visual rating of particulate on a filter membrane against ASTM Color Standards.3.1.5 membrane filter, na porous article of closely controlled pore size through which a liquid is passed to separate matter insus
11、pension.1 This test method is under the jurisdiction ofASTM Committee D02 on Petroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility of SubcommitteeD02.C0.01 on Turbine Oil Monitoring, Problems and Systems.Current edition approved June 1, 2016Oct. 1, 2018. Published August
12、2016October 2018. Originally approved in 2012. Last previous edition approved in 20122016 asD7843 12.D7843 16. DOI: 10.1520/D7843-16.10.1520/D7843-18.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Stand
13、ardsvolume information, refer to the standards Document Summary page on the ASTM website.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible
14、to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes section appears at the end of this standardCopyrigh
15、t ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States13.2 Definitions of Terms Specific to This Standard:3.2.1 varnish, na thin, hard, lustrous, oil-insoluble deposit, composed primarily of organic residue, and most readily definableby color intens
16、ity. It is not easily removed by wiping with a clean, dry, soft, lint-free wiping material and is resistant to saturatedsolvents. Its color may vary, but it usually appears in gray, brown, or amber hues.4. Summary of Test Method4.1 Insoluble deposits are extracted from an in-service turbine oil samp
17、le using a 47 mm, 0.45 m membrane nitro-cellulosepatch. The color of the patch is then analyzed using a spectrophotometer and the results are reported as a E value in the CIE LABscale.5. Significance and Use5.1 This test can be a guide to end-users on the formation of lubricant-generated, insoluble
18、deposits.5.2 The results from this test are intended to be used as a condition monitoring trending tool as part of a comprehensiveprogram, as outlined in standards such as Practice D4378.6. Apparatus6.1 Variations of apparatus, particularly with respect to filter membranes and vacuum pump setting, c
19、an affect the test resultssignificantly.6.2 When the user of this test method uses an alternate membrane filter, it is incumbent upon them to establish that the alternatefilter 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-t
20、ip.6.3.3 Borosilicate Filter Holder.6.3.4 Borosilicate Filtering Flask.6.3.5 Wash Bottle equipped with 0.22 m membranes.6.3.6 Vacuum Source, capable of maintaining a vacuum of 71 kPa 6 5 kPa.6.3.7 Graduated cylinder, 150 mL to 200 mL.6.3.8 Beaker, 100 mL to 250 mL.6.3.9 Petri dish.6.3.10 Spectrophot
21、ometer, with capabilities of analyzing a standard 15 mm target with a 0/45 measuring geometry, 10observer, 10 nm spectral intervals minimum resolution, the visible spectral range of 400 nm to 700 nm and CIELAB measuringindices.7. Reagents and Materials7.1 Petroleum Spirit (also known as petroleum et
22、her or IP Petroleum Spirit 40/60) (WarningExtremely flammable. Harmfulif inhaled. Vapors are easily ignited by electrostatic discharges, causing flash fire.), having boiling range from 35 C to 60 C.7.2 Coleman Camp FuelColeman Fuel is a complex mixture of light hydrocarbons (primarily aliphatic) pro
23、duced bydistillation of petroleum. Carbon number range is C5 to C9, and contains less than 0.001 % benzene.7.3 Purity of ReagentsReagent grade chemicals shall be used in all tests. Unless otherwise indicated, it is intended that allreagents conform to the specifications of the Committee of Analytica
24、l Reagents of the American Chemical Society where suchspecifications are available. Other grades may be used, provided it is first ascertained that the reagent is of sufficiently high purityto permit its use without lessening the accuracy of the determination.8. Sampling, Test Specimens, and Test Un
25、its8.1 Using either Practice D4057 (manual sampling) or Practice D4177 (automatic sampling), obtain a representative sample ofat least 60 mL of the material to be tested.NOTE 1The sample container used shall preclude exposure to UV light as oil is known to be sensitive to both indoor and outdoor sou
26、rces. Fluorescentlight is known to contain UV components and has been shown to increase deposit levels. This exposure can occur upon drawing of the sample as wellas during incubation period. Wide-mouth laboratory quality amber high-density polyethylene (HDPE) bottles have been shown to protect the o
27、il samplefrom UV light exposure. Other translucent or clear sample bottles are acceptable for use provided that the sample bottle, upon drawing of the sample andthroughout the heating/incubation process, is immediately placed and stored into packaging or a storage unit that blocks light. Cylindrical
28、 cardboardpackaging containers meet this intent.8.2 The sample shall be heated to 60 C to 65 C for 23 h to 25 h then stored between 15 C to 25 C, away from UV light foran incubation period of 68 h to 76 h. Samples that are analyzed prior to this aging period may produce fewer color bodies on thepatc
29、h; thus, producing a lower E value, and may lower the value of trend analysis.NOTE 2Samples can be analyzed in longer or shorter intervals with agreement of the end-user. The level of deposit and as a consequence, the testD7843 182results may be affected by time duration chosen. It is sometimes sugg
30、ested to additionally analyze the sample at multiple incubation periods to fullyunderstand the operating system.9. Procedure9.1 Preparation of Sample and Materials:9.1.1 Document the date and time at the beginning of the test.9.1.2 Vigorously mix the sample for 15 s minimum to resuspend insolubles u
31、niformly. Visually inspect the inside of the bottlefor evidence of material adherent to the surface of the bottle before sampling.NOTE 3If adherent material cannot be removed from bottle after repeated attempts to vigorously mix, include as comment in the reportingdocumentation.9.1.3 Transfer 50 mL
32、6 1 mL of sample into clean beaker or Erlenmeyer flask.9.1.4 Add approximately 50 mL 6 1 mL of petroleum ether to beaker containing sample.9.1.5 Stir sample for approximately 30 s to ensure that a complete solution (and complete mixing) is attained.9.1.6 Pour sample into filter funnel within 1 min t
33、o 2 min of initial mixing.9.2 Filtration Process:9.2.1 Using forceps, mount the filter on the center of the filter 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 76 kPa is attained and held.9.2.4 Rinse the beaker twice with
34、 a minimum of 35 mL of petroleum ether and pour the rinsing into the filter funnel.9.2.5 Permit the filtrate to completely flow through.9.2.6 Carefully, remove the clamp and funnel. Wash any adhering insolubles from the funnel onto the membrane with petroleumether. Wash the membrane gently, particul
35、arly the edges, with petroleum ether from the wash bottle.NOTE 4If any of the deposits fails to remain on (or falls off) the dry membrane 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 the fil
36、ter holder and place into a clean dry petri-dish. To facilitate handling,the membrane filters might be rested on clean glass rods in the petri-dish.9.2.10 Dry the membrane by placing it in a low-level heat source free of ignition sources for flammable vapors, or air dry(typically, 3 h) in a dust-fre
37、e location. Dryness can be estimated by comparing the white color of the outer edge of the testmembrane with a new membrane.9.3 Color Determination of the Membrane Patch:9.3.1 Standardize the instrument using a patch developed from clean solvent application of the method to establish thebackground c
38、olor white.9.3.2 Follow the standardization procedure defined by the instrument manufacturer.9.3.3 Analyze the patch as recommended by the instrument manufacturer.9.3.4 Analyze the color of the patch in accordance with the equipment manufacturers instructions to produce a CIE LAB value.10. Calculati
39、on of Results10.1 CIE 1976 L* a* b* Uniform Color Space and Color-Difference EquationThis is an approximately uniform color spaceSystem defined by Practice E308. It is produced by plotting in rectangular coordinates the quantities L*, a*, b*, calculated asfollows:L*5116*Y Yn !13 2 16 (1)a*5500X Xn !
40、13 2 Y Yn!13# (2)b*5200Y Yn !13 2 Z Zn!13# (3)TABLE 1 72 h (3 day)Material AverageRepeatabilityStandardDeviationReproducibilityStandardDeviationRepeatabilityLimitReproducibilityLimitx sr sR r RSample 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 2.3
41、49 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 4.611D7843 183XXn ;YYn ; ZZn.0.01 (4)The tristimulus values Xn,Yn,Zn define the color of the normally white object-color stimulus, in this ca
42、se the new membranepatch. Under these conditions, Xn,Yn, and Zn are the tristimulus values of the standard 10 observer, D65 illuminant.10.1.1 The total difference E*ab between two colors each given in terms of L*, a*, b* is calculated as follows:E*ab 5L *!2 1a *!2 1b *!2 #12 (5)10.2 Reporting:10.2.1
43、 Report the spectrophotometer CIE LAB E values to one decimal place.10.2.2 The incubation after heating shall be reported with the E value.10.2.3 Note in the reporting documentation any deviation from this Standards methodology.11. Precision and Bias311.1 The precision of this test method is based o
44、n an interlaboratory study conducted in 2011. Twelve laboratories participatedin the study, testing seven different turbine oils, over three and five day periods. Every analyst was instructed to report duplicatetest results in this study. Practice E691 was followed for the study design; the details
45、are given in ASTM Research ReportRR:D02-1752.11.1.1 Repeatability limit (r)Two test results obtained within one laboratory shall be judged not equivalent if they differ bymore than the “r” value for that material; “r” is the interval representing the critical difference between two test results for
46、the samepoint, obtained by the same operator using the 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 test results shall be judged not equivalent if they differ by more than the “R” value forthat ma
47、terial; “R” is the interval representing the critical difference between two test results for the same point, obtained bydifferent operators using different equipment in different laboratories.11.1.2.1 Reproducibility limits are listed in Tables 1 and 2.11.1.3 The above terms (repeatability limit an
48、d reproducibility limit) are used as specified in Practice E177.11.1.4 Any judgment in accordance with statements 9.1.1 and 9.1.2 would have an approximate 95 % probability of beingcorrect.11.2 BiasAt the time of the study, there was no accepted reference material suitable for determining the bias f
49、or this testmethod, therefore no statement on bias is being made.11.3 The precision statement was determined through statistical examination of 312 test results, from a total of twelvelaboratories, on seven turbine oils. The seven materials were described as:Sample 1: 2011Sept-1, 3 day heating experiment for the 3 day waitafter heating + 2011Sept-1, 5 day heating experiment for the 5 daywait after heatingSample 2: 2011Sept-2, 3 day heating experiment for the 3 day waitafter heating + 2011Sept-2, 5 day he
