1、Designation: D6895 06 (Reapproved 2012)Standard Test Method forRotational Viscosity of Heavy Duty Diesel Drain Oils at100C1This standard is issued under the fixed designation D6895; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, t
2、he 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 covers the determination of the rota-tional viscosity and the shear thinning properties of
3、 heavy dutydiesel engine drain oils at 100C, in the shear rate range ofapproximately 10 to 300 s-1, in the shear stress range ofapproximately 0.1 to 10 Pa and the viscosity range of approxi-mately 12 to 35 mPas. Rotational viscosity values can becompared at a shear rate of 100 s-1by this test method
4、.2,31.2 This standard does not purport to address all of thesafety concerns, 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. Referenc
5、ed Documents2.1 ASTM Standards:4D4057 Practice for Manual Sampling of Petroleum andPetroleum ProductsD5967 Test Method for Evaluation of Diesel Engine Oils inT-8 Diesel EngineD6299 Practice for Applying Statistical Quality Assuranceand Control Charting Techniques to Evaluate AnalyticalMeasurement Sy
6、stem Performance3. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 maximum point timeinstrument setting that limitsthe amount of time the instrument will maintain a constantshear stress or shear rate before accepting the value as theequilibrium value.3.1.2 rate indexthe exponent,
7、 c, in these expressionsrelating shear rate and shear stress:shear stress 5 bshear rate!c(1)lnshear stress! 5 lnb1clnshear rate! (2)3.1.2.1 DiscussionA rate index of c = 1 signifies Newto-nian fluid behavior. Values less than one indicate increasingnon-Newtonian, shear thinning behavior.33.1.3 rotat
8、ional viscositythe viscosity obtained by use ofthis test method.3.1.4 VIS100 DECrotational viscosity at shear rate of 100s-1, decreasing shear stress or shear rate sweep.3.1.5 VIS100 INCrotational viscosity at shear rate of 100s-1, increasing shear stress or shear rate sweep.4. Summary of Test Metho
9、d4.1 The sample is placed in a controlled stress or controlledshear rate rheometer/viscometer at 100C. The sample ispresheared at 10 s-1for 30 s followed by heating at 100C for10 min. An increasing shear rate (approximately 10 to 300 s-1)or shear stress (0.1 to 10 Pa) sweep is run followed by adecre
10、asing sweep. The rotational viscosity for each step(increasing and decreasing) at 100 s-1shear rate is interpolatedfrom the viscosity versus shear rate data table. The rate index,as a measure of shear thinning, is calculated from a plot of ln(shear stress) versus ln (shear rate).5. Significance and
11、Use5.1 Rotational viscosity measurements allow the determina-tion of the non-Newtonian, shear thinning property of drain oil.Rotational viscosity values can be compared at a shear rate of100 s-1by this test method.2,36. Apparatus6.1 This test method uses rheometers/viscometers of thecontrolled stres
12、s or controlled rate mode of operation. The testmethod requires the use of concentric cylinder measuringgeometry or cone and plate measuring geometries, with a1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products and Lubricants and is the direct responsibility of Sub
13、committeeD02.07 on Flow Properties.Current edition approved Nov. 1, 2012. Published November 2012. Originallyapproved in 2003. Last previous edition approved in 2006 as D689506. DOI:10.1520/D6895-06R12.2Selby, K., “Rheology of Sootthickened Diesel Engine Oils,” SAE 981369,May 1998.3George, H. F., Ba
14、rdasz, E. A., and Soukup, B., “Understanding SMOT throughDesigned Experimentation Part 3: An Improved approach to Drain Oil ViscosityMeasurementsRotational Rheology,” SAE 97692, May 1997.4For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at servicea
15、stm.org. For Annual Book of ASTMStandards volume information, 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 States1minimum cone diameter of 50 mm, capable of operating in ther
16、ange of approximately 0.1 to 10 Pa for shear stress and 10 to300 s-1for shear rate.6.2 Instrument data logging or software shall be capable ofdelivering shear stress versus shear rate data and viscosityversus shear rate data in tabular form. During the experiment,a minimum of 20 points must be taken
17、. The method for datalogging shall be an equilibrium method where the controlledstress or controlled rate value is held constant until the datapoint equilibrium is reached. The use of a maximum point timeis acceptable, but it must be set to at least 30 s.6.3 Temperature shall be controlled to 100 6
18、0.2C atequilibrium. Some rheometers have a 99.9C set point limitand would be acceptable for this test method.7. Reagents and Materials7.1 Standard Newtonian Reference Oil, calibrated in viscos-ity in the range of 12 to 35 mPas at 100C.8. Sampling, Test Specimens, and Test Units8.1 Ensure the test sp
19、ecimen is homogeneous. Engine sam-pling is generally specified in the test method, for example,Test Method D5967. Manual sampling from the container canbe done in accordance with Practice D4057.9. Preparation of Apparatus9.1 Prepare the apparatus in accordance with manufacturersdirections. The appar
20、atus shall be capable of viscosity mea-surement to within 5 % of the standard Newtonian reference oilviscosity and a rate index value of 0.98 to 1.02 indicating aNewtonian fluid.10. Calibration and Standardization10.1 A Newtonian viscosity standard in the range 12 to 35mPas at 100C shall be used to
21、verify instrument calibration.Run the procedure as in Section 12. A plot of shear stress (Pa)versus shear rate (s-1) shall be linearly regressed to yield aslope and intercept. Results shall be:Intercept, 0.9998This calibration procedure should be repeated if anycriteria are not metThe instrument man
22、ufacturer should be contacted if thecriteria cannot be metThe operator shall not proceed with this procedure if thecalibration criteria are not metNOTE 1It has been determined that use of a specific reference oil inthe aforementioned viscosity range did not improve the precision. Forlaboratory to la
23、boratory consistency, it is suggested to use Cannon S200 asthe standard calibration fluid.510.2 New SAE 15W-40 oil shall be used as a daily controlchart standard. Run the procedure (see Section 12) and performan analysis (see Section 13). Results shall be a rate indexbetween 0.98 to 1.02 and a visco
24、sity value at 100 s-1, mPas,VIS100. Control chart the values of VIS100 and rate index.The procedure shall be checked and the instrument calibrationrechecked if the reference oil does not fall within controllimits. Practice D6299 shall be used as a guide in this area.10.3 Some instruments and geometr
25、ies will exhibit signifi-cant instrument/electronic noise at low shear stress or lowshear rate levels, or both. This may be determined by plottingviscosity versus shear rate or viscosity versus shear stress formeasurements of the standard oil. A horizontal line is obtainedin regions far from noise.
26、Annex A1 shows two examples ofthis type of plot. The minimum shear rate or shear stress to usein the analysis of data can then be determined for the particularinstrument and geometry.11. Conditioning11.1 Shake all new and used oil samples using the followingprocedure. Do not prepare more than two sa
27、mples at one timefor one instrument.11.2 Ensure cap is tight on container.11.3 Shake vigorously by hand for 30 s. Wait 60 s for airbubbles to dissipate.11.4 A specimen of the sample shall be taken for analysispromptly following the shaking and dissipation procedure of11.3.12. Procedure12.1 Run the p
28、rocedure in accordance with the instrumentgeometry requirements and the manufacturers recommenda-tions to obtain shear stress versus shear rate data in the rangesof 0.1 to 10 Pa and 10 to 300 s-1. The order of steps is asfollows:12.1.1 Load sample.12.1.2 Equilibrate at 100C (minimum 5 min, maximum 1
29、0min).12.1.3 Preshear sample at 10 s-1for 30 s.12.1.4 Stop preshear.12.1.5 Preheat sample at 100C for 10 min.12.1.6 Run increasing stress or rate sweep for duration ofapproximately 10 min to generate data of shear stress, shearrate and viscosity followed immediately by the next step. Therun time wil
30、l vary somewhat among different instruments andprocedures. Times as low as 2 min and as high as 20 min havebeen utilized successfully to run this test method.12.1.7 Run decreasing stress or rate sweep for duration ofapproximately 10 min to generate data of shear stress, shearrate, and viscosity.12.1
31、.8 Clean sample from instrument in accordance with themanufacturers instructions. Cone and plate systems shall berinsed with a suitable solvent followed by wiping with a rag ortowel.13. Calculation or Interpretation of Results13.1 Analyze the increasing and decreasing sweeps sepa-rately.13.2 Import
32、the shear stress (Pa), shear rate (s-1) andviscosity (mPas) into a spreadsheet program. This calculation5The sole source of supply of the calibration fluid known to the committee at thistime is Cannon Instrument Co., P.O. Box 16, State College, PA 16804. If you areaware of alternative suppliers, ple
33、ase provide this information to ASTM Interna-tional Headquarters. Your comments will receive careful consideration at a meetingof the responsible technical committee,1which you may attend.D6895 06 (2012)2may be done with a calculator. Delete data below the noiselimit as determined in 10.3.13.3 Calcu
34、late two additional columns for ln (shear rate)and ln (shear stress). See Appendix X1 for sample calculation.13.4 Plot the ln stress versus ln rate columns as a scatter plotwith ln rate on the x-axis.13.5 Fit a least squares linear regression to the data plot.Obtain the equation of the line. This li
35、ne follows Eq 2. Thereis no criterion for correlation coefficient of candidate oils. SeeAppendix X1 for sample calculation.13.6 Obtain the slope of the line, c which is the rate index,to three decimal places and the intercept as ln b to four decimalplaces.13.7 Calculate the viscosity at 100 s-1by in
36、terpolationbetween two data points spanning 100 s-1as follows:VIS100 5 VIS11D 100 2 T1! (3)where:D = (VIS2 VIS1)/(T2 T1),VIS2 and T2 = viscosity and shear rate respectively at thefirst data point above 100 s-1, andVIS1 and T1 = viscosity and shear rate respectively at thefirst data point below 100 s
37、-1.14. Report14.1 Report the rate index value as c, the viscosity asVIS100 and intercept as ln b . Label increasing and decreasingsweep data using INC and DEC.14.2 Rate index c = dimensionless, three decimal places,x.xxx.14.3 VIS100 = mPas, two decimal places xx.xx.14.4 ln b = Pa, four decimal place
38、s, x.xxxx.15. Precision6,715.1 Precision was found to be dependent on the mean valueof the measured property. The data in this section was derivedfrom a six laboratory/six sample interlaboratory study and athree laboratory/seven sample interlaboratory study. All datawas pooled to generate the repeat
39、ability and reproducibilitydata. VIS100 range was 14.99 to 36.28 mPas and rate indexrange was 0.623 to 1.002.rRRate index, INC 0.140 0.128x 0.592 0.552xRate index, DEC 0.050 0.048x 0.490 0.480xVIS100, INC 0.12 + 0.0089y -2.08 + 0.168yVIS100, DEC 0.33 + 0.0066y -0.54 + 0.073ywhere:x = mean value of r
40、ate index, andy = mean value of VIS100 in mPas.15.2 Sample Precision Calculations :15.2.1 The maximum value for rate index is 1.000. Thisoccurs for fluids which exhibit Newtonian behavior as ob-served for fresh diesel oils within the shear rate range ofmeasurement in this test method. The rate index
41、, DEC repro-ducibility for fresh oils would be:0.490 2 0.480 1.000! 5 0.010and for a drain with a value of 0.900:0.490 2 0.480 0.900! 5 0.05815.2.2 The VIS100 precision values are valid for viscositieswithin the scope of this test method, 12 to 35 mPas. A drainwith a VIS100, DEC value of 15.20 mPas
42、would have arepeatability of:0.3310.0066 15.2! 5 0.430and a reproducibility of:20.5410.073 15.2! 5 0.57016. Keywords16.1 drain oils; heavy duty diesel; rotational viscosities;shear thinningANNEX(Mandatory Information)A1. TYPICAL EXAMPLE TO DETERMINE NOISE LEVEL AND MINIMUM SHEAR RATE VALUEA1.1 The d
43、ata are plotted as shown and the minimum noiselevel determined in the low shear region. Data below this levelare deleted for analysis. The examples in Fig. A1.1 and Fig.A1.2 are from two different cone and plate systems.6Supporting data have been filed at ASTM International Headquarters and maybe ob
44、tained by requesting Research Report RR:D02-1594.7Supporting data have been filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR:D02-1607.D6895 06 (2012)3APPENDIX(Nonmandatory Information)X1. ANALYSIS EXAMPLE OF DATA TABLEX1.1 Table X1.1 follows the directions
45、 in Section 13. Seealso Fig. X1.1.FIG. A1.1 Example 1FIG. A1.2 Example 2D6895 06 (2012)4ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of
46、 the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn.
47、Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comme
48、nts have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or m
49、ultiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).TABLE X1.1Shear Stress, Pa Shear Rate, 1/s Viscosity, Pas ln(Shear Rate) ln(Shear Stress)1.034 15.79 0.06551 2.759376828 0.0334347761.673 31.58 0.05299 3.452524009 0.5146184222.183 47.37 0.04608 3.857989117 0.78
