1、Designation: E3116 18Standard Test Method forViscosity Measurement Validation of RotationalViscometers1This standard is issued under the fixed designation E3116; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revi
2、sion. 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 provides procedures for validatingviscosity measurements by rotational viscometers of Newto-nian fluids. Perfo
3、rmance parameters determined include vis-cosity repeatability (precision), detection limit, quantitationlimit, linearity, and bias.1.2 Validation of apparatus performance and analyticalmethods is requested or required for quality initiatives or whereresults may be used for legal purposes.1.3 The val
4、ues stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.4 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 sa
5、fety, health, and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment o
6、f International Standards, Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2E177 Practice for Use of the Terms Precision and Bias inASTM Test MethodsE473 Terminology Relating to Thermal Analysis a
7、nd Rhe-ologyE1142 Terminology Relating to Thermophysical PropertiesE1970 Practice for Statistical Treatment of ThermoanalyticalDataE2161 Terminology Relating to Performance Validation inThermal Analysis and RheologyE2975 Test Method for Calibration or Calibration Verifica-tion of Concentric Cylinder
8、 Rotational Viscometers3. Terminology3.1 Definitions:3.1.1 Technical terms used in this standard are defined inPractice E177 and in Terminologies E473, E1142, and E2161including analyte, calibration, Celsius, detection limit,linearity, Newtonian, non-Newtonian, precision, quantitationlimit, referenc
9、e materials, relative standard deviation,repeatability, shear, slope, standard deviation, validation,viscometer, and viscosity.4. Summary of Test Method4.1 Viscosity is the primary dependent parameter and eithertorque or rotational speed is the primary independent parametermeasured by rotational vis
10、cometry. Viscosity is strongly de-pendent upon temperature and so temperature is usually heldconstant.4.2 Viscosity is validated by the direct measurement using aconcentric cylinder rotational viscometer at an isothermaltemperature using reference materials of known viscosity as ananalyte.4.3 Altern
11、atively, validation of a rotational viscometrymethod based upon viscosity measurement may be performedusing a specific test specimen as the analyte.4.4 The viscosity of three or more specimens, nominallyrepresenting the minimum, midpoint and maximum of therange of the test method, are measured at le
12、ast in triplicate.NOTE 1Repeatability is determined by performing a sufficient numberof determinations to calculate statistically valid estimates of the standarddeviation or relative standard deviation of the measurements.4.4.1 Viscosity linearity and bias are determined from thelinear regression (b
13、est-fit) straight-line correlation of the resultsfrom measurements of the three or more specimens.4.4.2 Viscosity repeatability, detection limits and quantita-tion limits are determined from the standard deviation of themeasurement of three or more analyte-containing specimens.1This test method is u
14、nder the jurisdiction ofASTM Committee E37 on ThermalMeasurements and is the direct responsibility of Subcommittee E37.08 on Rheol-ogy.Current edition approved Jan. 1, 2018. Published January 2018. DOI: 10.1520/E3116-18.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact
15、ASTM Customer Service at serviceastm.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 StatesThis international standard
16、was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.14.5 A spin
17、dle is rotated in a Newtonian fluid at a known (ormeasured) speed. The viscosity drag experienced by theimmersed spindle is measured (or known) as a torque. Viscos-ity may then be determined from these properties (torque androtational speed) and the dimensions of the spindle by equa-tions such as Eq
18、 1 and Eq 2. 5 S (1)S 5 rc22 rs2! 4 rc2rs2L! (2)where: = viscosity, Pa-s, = rotational speed, r/min, = torque, N-m,rc= radius of the cylindrically shaped container, m,rs= radius of the cylindrically shaped spindle, m,L = length of the cylindrically shaped spindle, m, andS = instrument or experimenta
19、l calibration constant, m-3.NOTE 21 Pa = 1 N/m2;60s=1min.5. Significance and Use5.1 This test method may be used to validate the perfor-mance of a specific rotational viscometer apparatus.5.2 This test method may be used to validate the perfor-mance of a specific method based upon the measurement of
20、viscosity using rotational viscometer apparatus.5.3 This test method may be used to determine the repeat-ability of a specific apparatus, operator, or laboratory.5.4 This test method may be used for specification orregulatory compliance purposes.6. Interferences6.1 Viscosity is highly dependent upon
21、 temperature. Mate-rials may change by as much as 7 % per Celsius degree. Forthis reason, all measurements shall be made in the sametemperature controlled environment.6.2 This test method assumes that the analyte exhibitsNewtonian behavior, that is viscosity is linearly dependentupon shear rate (rot
22、ational speed) and a linear applied force(torque). Many materials of interest, however, are non-Newtonian in nature where the measured viscosity varies withshear rate. Care shall be exercised in the selection of areference material analyte for this test method that is Newto-nian in nature.7. Apparat
23、us7.1 Viscometer, RotationalThe essential instrumental re-quired providing the minimum rotational viscometer analyticalcapabilities for this test method include:7.1.1 A drive motor, to apply a rotational displacement tothe specimen at a rate of 0.2 r/min to 200 r/min constant to60.2 % of full scale.
24、7.1.2 A coupling shaft or other means, to transmit therotational displacement from the motor to the specimen.NOTE 3It is convenient to have a mark on the shaft to indicate thefluid level of the test specimen appropriate for the measurement.7.1.3 A cylindrical rotational element, spindle, geometry, o
25、rtool, composed of a material inert to the material being tested,to fix the specimen between the coupling shaft and a stationaryposition.7.1.4 A sensor to measure the torque within 61 % of fullscale developed by the specimen.7.1.5 A temperature sensor to provide an indication of thespecimen temperat
26、ure over the range of 19 to 26C to within60.1C.7.1.6 A data collection device, to provide a means ofacquiring, storing, and displaying measured or calculatedsignals, or both. The minimum output signals required aretorque, rotational speed, temperature, and time.7.1.7 A stand, to support, level, lowe
27、r, and raise the drivemotor, shaft and rotational element.7.2 A specimen container, cylindrical or disk in shape, tocontain the test specimen during testing.NOTE 4The specific container may depend upon the rotationalelement being used (see vendors recommendations). In the absence ofother information
28、, a low form Griffin beaker of 600-mL capacity shall beused.7.3 A temperature bath and controller to provide a con-trolled isothermal temperature environment for the specimenwithin the range of 19 to 26C constant to within 60.1C.7.4 Auxiliary instrumentation considered useful in conduct-ing this tes
29、t method includes:7.4.1 Data analysis capability to provide viscosity, stress orother useful quantities derived from the measured signals.7.4.2 A level to indicate the vertical plumb of the drivemotor, shaft and rotational element.8. Reagents and Materials8.1 Three or more viscosity reference fluids
30、 (with accom-panying certificates) representing the minimum, midpoint andmaximum viscosity range to be validated by the procedure.NOTE 5Viscosity reference materials are typically available from theviscometer supplier.9. Preparation of Apparatus9.1 Perform any viscometer preparation or calibration p
31、ro-cedures described in the apparatus operations manual oraccording to Test Method E2975.9.2 Operate the viscometer in air with a connected rotationalelement in place. The indicator shall be stable and indicate azero value.9.3 Set the temperature bath at 25C and equilibrate for 30min. Measure the te
32、mperature bath and ensure that it is 25 60.2C.NOTE 6Other temperatures may be used but shall be reported.10. Procedure10.1 Place the required amount of medium viscosity refer-ence material in the specimen container. Record the referenceviscosity value from its certificate as medREF.NOTE 7The amount
33、of viscosity reference material needed varies witheach rotational element and container combination. See the instrumentE3116 182operations manual for the correct amount of liquid for each element-container pair.NOTE 8Pour the reference material slowly down the side of specimencontainer taking care t
34、o prevent incorporation of air bubbles into thematerial.10.2 Place the container with its reference material in thetemperature bath at 25 6 0.2C and equilibrate for 30 minutes.NOTE 9Other temperatures may be used but shall be reported.10.3 Vertically align and level the viscometer motor, shaftand ro
35、tational element on its supporting stand over the speci-men container.10.4 Slowly lower the rotational element into the testspecimen until the fluid reaches the appropriate level indicatedin the operations manual.NOTE 10The shaft may have a mark to indicate the appropriate fluidlevel for the measure
36、ment.NOTE 11Ensure that no air bubbles are trapped under the rotationalelement.10.5 Initiate the rotation of the rotational element at 0.5r/min for 30 min.10.6 Increase (or decrease) the rotational speed to thatrequired to produce a reading nearest the midpoint of the scale.10.7 Stop the rotation of
37、 the element and wait for 1 min.10.8 Restart the rotational at the same rotational speed (ortorque) and allow at least 5 revolutions of the element.10.9 Measure and record the observed viscosity med1 (ortorque med1), rotational speed med1 and temperature Tmed1.NOTE 12If the temperature is not 25.0 6
38、 0.2C, discard themeasurement, allow the test specimen to equilibrate for an additional 30min or until the desired temperature range and stability is observed, andremeasure.10.10 Repeat steps 10.7 through 10.9 two more times,measuring the indicated viscosity as med2 and med3 (ortorque med2 and med3)
39、, rotational speed med2 and med3, andtemperature Tmed2 and Tmed3.10.11 Using the three (nmed= 3) values for viscosity fromsteps 10.9 and 10.10, calculate the mean value for medandmed(see Practice E1970).10.12 Repeat steps 10.1 through 10.11 for (nmax=3)themaximum viscosity reference material recordi
40、ng maxREF,max1, max2, max3, max1, max2, max3, Tmax1, Tmax2, andTmax3.10.13 Determine the mean viscosity value for max and itsstandard deviation max.10.14 Repeat steps 10.1 through 10.10 for (nmin=3)theminimum viscosity reference material recording minREF,min1, min2, min3, min1, min2, min3, Tmin1, Tm
41、in2, andTmin3.10.15 Calculate the mean viscosity value for minand itsstandard deviation min.10.16 Using the values from 10.11, 10.13, and 10.15 and Eq3, calculate the viscosity relative standard deviation forRSDmin, RSDmed, and RSDmax.10.17 Using the values from 10.11, 10.13, 10.15, and 10.16and Eq
42、4, calculate the repeatability value r.10.18 Calculate the detectability limit (DL) using Eq 5.10.19 Calculate the quantitation limit (QL) using Eq 6.10.20 Using the reference viscosity values (xREF) for theminimum (min), medium (med) and maximum (max) viscosityreference material from steps 10.1, 10
43、.12, and 10.14 as theindependent (X) values and the three (or more) determinedmean viscosity values from steps 10.11, 10.13, and 10.15 as thedependent (Y) values, determine by linear regression the slope(m), and intercept (b) of a correlation best-fit line (see PracticeE1970).NOTE 13The value of m w
44、ill be close to unity. b has the units ofviscosity (nominally Pa-s).10.21 Determine the deviation values (Ymin, Ymed, andYmax) for each of the mean minimum, medium, and maximumviscosity values using Eq 7 and the values of m and b from10.20.10.22 Determine which deviation value from step 10.21 hasthe
45、 largest absolute value and identify it as Ylargest.10.23 Determine linearity (L) using Eq 8.10.24 Determine the bias using Eq 9.11. Calculations11.1 Relative standard deviation (RSD) is given by Eq 3 (seePractice E1970):RSD 5 3100 % mean value (3)11.2 The repeatability (r) value is given by Eq 4:r
46、5 sfhsnmin2 1d RSDmin2j1hsnmed2 1d RSDmed2j1hsnmax2 1d RSDmax2jg fsnmin2 1d1snmed2 1d1snmax2 1dgd12(4)E3116 18311.3 The detection limit (DL) is given by Eq 5:DL 5 3.3 r min 100 % (5)11.4 The quantitation limit (QL) is given by Eq 6:QL 5 10 r min 100 % (6)11.5 Correlation slope (m) and intercept (b)
47、are obtainedfrom a display of the measured viscosity values from 10.10,10.12, and 10.14 on the Y-axis and reference viscosity valuesfrom 10.11, 10.13, and 10.15 on the X-axis such as that shownin Fig. 1. Using linear regression (see Practice E1970) deter-mine the slope (m) and intercept (b) of the c
48、orrelation line.11.6 Deviation is given by Eq 7:Y 5? 2 m REF 2 b?(7)where: = the experimentally determined mean viscosity value(from steps 10.11, 10.13, and 10.15), andREF = the corresponding known viscosity reference value.11.6.1 Select the largest Y value as Ylargest.11.7 Percent linearity (L) is
49、given by:L 5 100 % 3 Ylargest! m 3 maxREF 1 b!# (8)11.8 Bias (Bias) is given by:Bias 5 b (9)12. Example Calculations12.1 For the example calculations described below, thefollowing experimental values are used:minREF = 200.0 mPa-smedREF = 500.0 mPa-smaxREF = 800.0 mPa-smin= 190.0 mPa-smed= 487.5 mPa-smax= 800.0 mPa-snmin=3nmed=3nmax=3min= 2.0 mPa-smed= 5.0 mPa-smax= 5.4 mPa-s12.1.1 Relative Standard Deviation:RSDmin= 2.0 mPa-s 100 % / 190.0 mPa-s = 1.05 %RSDmed= 5.0 mPa-s
