1、Designation: D7483 13aStandard Test Method forDetermination of Dynamic Viscosity and Derived KinematicViscosity of Liquids by Oscillating Piston Viscometer1This standard is issued under the fixed designation D7483; the number immediately following the designation indicates the year oforiginal adopti
2、on 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 covers the measurement of dynamicviscosity and derivatio
3、n of kinematic viscosity of liquids, suchas new and in-service lubricating oils, by means of anoscillating piston viscometer.1.2 This test method is applicable to Newtonian and non-Newtonian liquids; however the precision statement was de-veloped using Newtonian liquids.1.3 The range of dynamic visc
4、osity covered by this testmethod is from 0.2 mPas to 20 000 mPas (which is approxi-mately the kinematic viscosity range of 0.2 mm2/s to 22 000mm2/s for new oils) in the temperature range between 40 to190C; however the precision has been determined only fornew and used oils in the range of 34 to 1150
5、 mPas at 40C, 5.7to 131 mPas at 100C, and 46.5 to 436 mm2/s at 40C.1.4 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.5 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It
6、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:2D445 Test Method for Kinematic Viscosity of Transparentand Opaque Liquids (and Ca
7、lculation of Dynamic Viscos-ity)D2162 Practice for Basic Calibration of Master Viscometersand Viscosity Oil StandardsD4057 Practice for Manual Sampling of Petroleum andPetroleum ProductsD4177 Practice for Automatic Sampling of Petroleum andPetroleum ProductsD5967 Test Method for Evaluation of Diesel
8、 Engine Oils inT-8 Diesel EngineD6300 Practice for Determination of Precision and BiasData for Use in Test Methods for Petroleum Products andLubricantsD6708 Practice for Statistical Assessment and Improvementof Expected Agreement Between Two Test Methods thatPurport to Measure the Same Property of a
9、 MaterialD6792 Practice for Quality System in Petroleum Productsand Lubricants Testing Laboratories2.2 ISO Standards:3ISO/EC 17025 General Requirements for the Competenceof Testing and Calibration Laboratories2.3 NIST Standard:4NIST Technical Note 1297 Guideline for Evaluating andExpressing the Unce
10、rtainty of NIST Measurement Results3. Terminology3.1 Definitions:3.1.1 dynamic viscosity (), nthe ratio between the appliedshear stress and rate of shear of a liquid.3.1.1.1 DiscussionIt is sometimes called the coefficient ofdynamic viscosity or, simply, viscosity. Thus, dynamic viscos-ity is a meas
11、ure of the resistance to flow or to deformation ofa liquid under external shear forces.3.1.1.2 DiscussionThe term dynamic viscosity can also beused in a different context to denote a frequency-dependantquantity in which shear stress and shear rate have a sinusoidaltime dependence.3.1.2 kinematic vis
12、cosity (), nthe ratio of the dynamicviscosity () to the density () of a liquid.3.1.2.1 DiscussionFor gravity flow under a given hydro-static head, the pressure head of a liquid is proportional to its1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products and Lubricants
13、 and is the direct responsibility of SubcommitteeD02.07 on Flow Properties.Current edition approved June 15, 2013. Published July 2013. Originallyapproved in 2008. Last previous edition approved in 2013 as D7483 13 DOI:10.1520/D7483-13A.2For referenced ASTM standards, visit the ASTM website, www.ast
14、m.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from International Organization for Standardization (ISO), 1, ch. dela Voie-Creuse, Case postale 56, CH-1211, Gen
15、eva 20, Switzerland, http:/www.iso.ch.4Available from http:/physics.nist.gov/ccu/Uncertainty/index.html.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1density, (). Ther
16、efore the kinematic viscosity, (), is a measureof the resistance to flow of a liquid under gravity.3.1.3 rate of shear (shear rate), n in liquid flow, thevelocity gradient across the liquid.3.1.4 shear stress, nthe force per unit area in the directionof the flow.3.1.4.1 DiscussionThe SI unit for she
17、ar stress is the pascal(Pa).3.1.5 density (), nmass per unit volume.3.2 Definitions of Terms Specific to This Standard:3.2.1 oscillating piston viscometer, na device that mea-sures the travel time of a piston driven electromagnetically intostationary oscillating motion through a liquid at a controll
18、edforce in order to determine the dynamic viscosity of the liquid.4. Summary of Test Method4.1 A specimen of sample is placed in the thermallycontrolled measurement chamber where the piston resides. Thepiston is driven into oscillatory motion within the measurementchamber by a controlled magnetic fi
19、eld. Once the sample is atthe test temperature, as determined by the temperature detector,the piston is propelled repeatedly through the liquid (by themagnetic field). A shear stress (ranging from 5 Pa to 750 Pa) isimposed on the liquid under test due to the piston travel. Thedynamic viscosity is de
20、termined by measuring the averagetravel time of the piston. The kinematic viscosity is derived byadditionally measuring the ratio between the up and downtravel times. This information is then applied to a calibrationcurve using liquids of known viscosity to calculate the dynamicviscosity. The kinema
21、tic viscosity is derived by an externallymeasured density by additionally measuring the ratio betweenthe up and down travel times. The precision and bias data forkinematic viscosity (as published in RR:D02-17555) werederived by externally measured density and do not apply to theinternal density meas
22、urement.5. Significance and Use5.1 Many petroleum products, as well as non-petroleummaterials, are used as lubricants for bearings, gears, compres-sor cylinders, hydraulic equipment, etc. Proper operation ofthis equipment depends upon the viscosity of these liquids.5.2 Oscillating piston viscometers
23、 allow viscosity measure-ment of a broad range of materials including transparent,translucent and opaque liquids. The measurement principle andstainless steel construction makes the Oscillating Piston Vis-cometer resistant to damage and suitable for portable opera-tions. The measurement itself is au
24、tomatic and does not requirean operator to time the oscillation of the piston. The electro-magnetically driven piston mixes the sample while under test.The instrument requires a sample volume of less than 5 mL andtypical solvent volume of less than 10 mL which minimizescleanup effort and waste.6. Ap
25、paratus6.1 Oscillating Piston Viscometer:6,76.1.1 The oscillating piston viscometer (see Fig. 1) com-prises a measurement chamber and calibrated piston capable ofmeasuring the dynamic viscosity within the limits of precisiongiven in Section 16.6.1.2 PistonFree moving, magnetically driven bodywithin
26、a Oscillating Piston Viscometer which is used formeasuring the viscosity of liquids. Individual pistons are sizedto measure specific viscosity ranges by varying the sensorannulus. See Table 1 for the selection of the piston accordingto the viscosity range.5Supporting data have been filed at ASTM Int
27、ernational Headquarters and maybe obtained by requesting Research Report RR:D02-1755. ContactASTM CustomerService at serviceastm.org.6The Oscillating Piston Viscometer is covered by a patent. Interested parties areinvited to submit information regarding the identification of an alternative to thispa
28、tented item to the ASTM International headquarters. Your comments will receivecareful consideration at a meeting of the responsible technical committee, whichyou may attend.7The sole sources of supply for the apparatus known to the committee at thistime is Cambridge Viscosity Inc., 101 Station Landi
29、ng, Medford, MA 02155(). If you are aware of alternative suppliers, pleaseprovide this information to ASTM International Headquarters. Your comments willreceive careful consideration at a meeting of the responsible technical committee,which you may attend.FIG. 1 Viscometer with ElectronicsD7483 13a2
30、6.1.3 Measurement ChamberLocation within OscillatingPiston Viscometer where piston motion (through the liquidunder test) occurs due to an imposed electromagnetic field. SeeFig. 2.6.1.4 ElectronicsCapable of controlling the electromag-netic field to propel and detect the travel time of the piston wit
31、ha discrimination of 0.01 s or better and uncertainty within60.07 %. The travel time is calibrated to be between 0.4 s and60 s, at a distance of 5 mm.6.1.5 Temperature Controlled JacketSufficient for main-taining measurement chamber temperature within 60.06C.6.1.6 Temperature Measuring DeviceIndustr
32、ial platinumresistance thermometer (IPRT) or equivalent sensor with amaximum permissible error of 60.02C. It is recommended,that the temperature measuring device be verified with anindependent, calibrated temperature probe at the test tempera-ture.6.2 Temperature Regulation System:6.2.1 Any liquid b
33、ath or thermoelectric means for regulatingthe jacket temperature.6.2.2 The temperature control must be such that the tem-perature of the measurement chamber is held within 60.06Cof the desired measurement temperature.6.3 Sample Introduction MechanismA syringe,micropipette, or flow-through adapter fo
34、r introducing between3.2 mL and 5 mL, inclusive by pressure, into the measurementchamber.7. Reagents and Materials7.1 Certified viscosity reference standards shall be certifiedby a laboratory that has been shown to meet the requirementsof ISO/EC 17025 by independent assessment. Viscosity stan-dards
35、shall be traceable to master viscometer proceduresdescribed in Practice D2162.7.2 The uncertainty of the certified viscosity referencestandard shall be stated for each certified value (k = 2, 95 %confidence). See ISO/EC 17025 or NIST TN 1297.7.2.1 The certified viscosity reference should have a pub-
36、lished viscosity in accordance with Test Method D445 orequivalent means that is close to that of the liquids being testedat the test temperature. For example, if intended measurementsare to be made from 5-25 mPas at 100C, then a reference oilviscosity of 15 mPas at 100C would be appropriate.7.3 Clea
37、ning solvents miscible with the sample and chemi-cally compatible with the wetted viscometer components (suchas alcohols, toluene, etc.). These wetted components aretypically 316L and 430 Stainless Steel.7.4 Quality control (QC) liquid similar to 7.1, but withviscosity values internally certified as
38、 noted in 12.2.8. 8. Sampling, Samples, and Test Units8.1 Ensure that the sample is homogenous. Engine samplingis generally specified in the test method, for example TestMethod D5967. When applicable, refer to Practice D4057(manual) or Practice D4177 (automatic) for proper samplingtechniques.9. Prep
39、aration of Apparatus9.1 Place the viscometer on a stable surface.9.2 Select the viscosity output units. If kinematic viscosityis selected, some apparatus will internally determine density toderive kinematic viscosity. Otherwise, enter the known densityand operate the unit according to the procedure
40、in Section 13.9.3 Verify calibration accuracy by testing a reference stan-dard or QC liquid at the test temperature. Follow the procedurein Section 13.10. Calibration and Standardization10.1 Calibrate according to manufacturers instructions toobtain a calibration curve (using two test liquids with r
41、efer-enced viscosity values near, but within, the extremes of thepiston range being used).10.2 Certified Viscosity Standards may be used as confir-matory checks on the procedure in the laboratory. This proce-dure is outlined in Section 13. If the dynamic viscosity result,at the calibration test poin
42、t, does not agree with the certifiedvalue within the limits of precision in Section 16, each step inthe procedure should be rechecked, as well as the temperaturemeasuring device and viscometer calibration, to locate thesource of error. If the source is not detected, consult themanufacturer.11. Sampl
43、e Conditioning11.1 Shake all new and used oil samples using the followingprocedure.TABLE 1 Viscosity Ranges of Oscillating Viscometer PistonsMinimum Viscosity (mPas ) Maximum Viscosity (mPas ) Piston Designation Nominal Piston Diameter (mm) Recommended Sample Volume(mL)0.02 2 SP20 7.87 3.250.25 5 SP
44、50 7.83 3.250.5 10 SP11 7.81 3.251 20 SP21 7.76 3.552.5 50 SP51 7.68 3.555 100 SP12 7.62 3.5510 200 SP22 7.54 3.5525 500 SP52 7.34 3.5550 1000 SP13 7.21 4.05100 2000 SP23 6.96 4.05250 5000 SP53 6.27 4.05500 10 000 SP14 6.05 4.051000 20 000 SP24 5.72 4.05D7483 13a311.1.1 Ensure cap is tight on the co
45、ntainer.11.1.2 Shake vigorously by hand for 30 s. Wait 10 s, orlonger if needed, for air bubbles to dissipate.11.1.3 A specimen of the sample shall be taken by pipette,pouring or pumping. Suspected nonhomogeneous samplesmust be conveyed for analysis promptly following the shakingand dissipation proc
46、edure of step 11.1.2.12. Quality Control/Quality Assurance (QC/QA)12.1 Confirm proper performance of the instrument and thetest procedure by analyzing reference oil as QC sample.12.2 If suitable reference oil is not available, prepare a QCsample by replicate analyses of a batch of oil sample. Thenst
47、atistically analyze the data to assign a mean value anduncertainty limit to the sample.12.3 When QC/QA protocols are already established in thetesting facility, these may be used to confirm the reliability ofthe test result.12.4 When there is no QC/QA protocol established in thetesting facility, gui
48、dance may be obtained from PracticeD6792.13. Procedure13.1 Verify or set the temperature control settings, as testedwith the control standard, so the viscometer temperature readsthe desired set point 60.06C while the piston is in motion.13.2 Remove the piston and clean the specimen from themeasureme
49、nt chamber as described in the viscometer manual.13.3 Load the measurement chamber with sample using thevolume listed in Table 1 related to the piston size being usedfor the viscosity range anticipated. To minimize contamination,and if sample volume allows, pre-wet the chamber and pistonwith the sample material and dry wipe with a lint free cloth.13.4 Load the measurement chamber with a clean piston.The piston size should be selected such that the measuredviscosity is between the minimum and maxim
