1、Designation: D7483 08D7483 13Standard 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
2、 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 Scope*1.1 This test method covers the measurement of dynamic viscosity
3、 and derivation of kinematic viscosity of liquids, such as newand in-service lubricating oils, by means of an oscillating piston viscometer.1.2 This test method is applicable to Newtonian and non-Newtonian liquids; however the precision statement was developedusing Newtonian liquids.1.3 The range of
4、 dynamic viscosity covered by this test method is from 0.2 mPas to 20 000 mPas (which is approximately thekinematic viscosity range of 0.2 mm2/s to 22 000 mm2/s for new oils) in the temperature range between 40 to 190C; howeverthe precision has been determined only for new and used oils in the range
5、 of 1.434 mPas to 154.4 mPas at temperatures of 40and 100C (as stated in34 to 1150 mPas at 40C, 5.7 to 131 mPas at 100C, and 46.5 to 436 mm2 the precision section)./s at 40C.1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
6、1.5 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 and health practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Doc
7、uments2.1 ASTM Standards:2D445 Test Method for Kinematic Viscosity of Transparent and Opaque Liquids (and Calculation of Dynamic Viscosity)D2162 Practice for Basic Calibration of Master Viscometers and Viscosity Oil StandardsD4057 Practice for Manual Sampling of Petroleum and Petroleum ProductsD4177
8、 Practice for Automatic Sampling of Petroleum and Petroleum ProductsD5967 Test Method for Evaluation of Diesel Engine Oils in T-8 Diesel EngineD6300 Practice for Determination of Precision and Bias Data for Use in Test Methods for Petroleum Products and LubricantsD6708 Practice for Statistical Asses
9、sment and Improvement of Expected Agreement Between Two Test Methods that Purportto Measure the Same Property of a MaterialD6792 Practice for Quality System in Petroleum Products and Lubricants Testing Laboratories2.2 ISO Standards:3ISO/EC 17025 General Requirements for the Competence of Testing and
10、 Calibration Laboratories2.3 NIST Standard:4NIST Technical Note 1297 Guideline for Evaluating and Expressing the Uncertainty of NIST Measurement Results3. Terminology3.1 Definitions:3.1.1 dynamic viscosity (), nthe ratio between the applied shear stress and rate of shear of a liquid.1 This test meth
11、od is under the jurisdiction of ASTM Committee D02 on Petroleum Products and Lubricants and is the direct responsibility of Subcommittee D02.07 onFlow Properties.Current edition approved Dec. 15, 2008March 1, 2013. Published February 2009 March 2013. Originally approved in 2008. Last previous editio
12、n approved in 2008 asD7483-08. DOI: 10.1520/D7483-08. 10.1520/D7483-13.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the AST
13、M website.3 Available from International Organization for Standardization (ISO), 1, ch. de la Voie-Creuse, Case postale 56, CH-1211, Geneva 20, Switzerland, http:/www.iso.ch.4 Available from http:/physics.nist.gov/ccu/Uncertainty/index.html.This document is not an ASTM standard and is intended only
14、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 to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
15、of the standard as published by ASTM is to be considered the official document.*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 States13.1.1.1 DiscussionIt is sometimes called t
16、he coefficient of dynamic viscosity or, simply, viscosity. Thus, dynamic viscosity is a measure of theresistance to flow or to deformation of a liquid under external shear forces.3.1.1.2 DiscussionThe term dynamic viscosity can also be used in a different context to denote a frequency-dependant quan
17、tity in which shear stressand shear rate have a sinusoidal time dependence.3.1.2 kinematic viscosity (), nthe ratio of the dynamic viscosity () to the density () of a liquid.3.1.2.1 DiscussionFor gravity flow under a given hydrostatic head, the pressure head of a liquid is proportional to its densit
18、y, (). Therefore thekinematic viscosity, (), is a measure of the resistance to flow of a liquid under gravity.3.1.3 rate of shear (shear rate), n in liquid flow, the velocity gradient across the liquid.3.1.4 shear stress, nthe force per unit area in the direction of the flow.3.1.4.1 DiscussionThe SI
19、 unit for shear 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 measures the travel time of a piston driven electromagnetically intostationary oscillating motion through a liquid
20、at a controlled force in order to determine the dynamic viscosity of the liquid.4. Summary of Test Method4.1 A specimen of sample is placed in the thermally controlled measurement chamber where the piston resides. The piston isdriven into oscillatory motion within the measurement chamber by a contro
21、lled magnetic field. Once the sample is at the testtemperature, as determined by the temperature detector, the piston is propelled repeatedly through the liquid (by the magneticfield). A shear stress (ranging from 5 Pa to 750 Pa) is imposed on the liquid under test due to the piston travel. The dyna
22、micviscosity is determined by measuring the average travel time of the piston. The kinematic viscosity is derived by additionallymeasuring the ratio between the up and down travel times. This information is then applied to a calibration curve using liquidsof known viscosity to calculate the dynamic
23、viscosity and kinematic viscosity of the liquid. See Fig. 1.FIG. 1 Cross Sectional View of Measurement ChamberD7483 1325. Significance and Use5.1 Many petroleum products, as well as non-petroleum materials, are used as lubricants for bearings, gears, compressorcylinders, hydraulic equipment, etc. Pr
24、oper operation of this equipment depends upon the viscosity of these liquids.5.2 Oscillating piston viscometers allow viscosity measurement of a broad range of materials including transparent, translucentand opaque liquids. The measurement principle and stainless steel construction makes the Oscilla
25、ting Piston Viscometer resistantto damage and suitable for portable operations. The measurement itself is automatic and does not require an operator to time theoscillation of the piston.The electromagnetically driven piston mixes the sample while under test.The instrument requires a samplevolume of
26、less than 5 mL and typical solvent volume of less than 10 mL which minimizes cleanup effort and waste.6. Apparatus6.1 Oscillating Piston Viscometer:566.1.1 The oscillating piston viscometer (see Fig. 2) comprises a measurement chamber and calibrated piston capable ofmeasuring the dynamic viscosity w
27、ithin the limits of precision given in Section 16.6.1.2 PistonFree moving, magnetically driven body within a Oscillating Piston Viscometer which is used for measuring theviscosity of liquids. Individual pistons are sized to measure specific viscosity ranges by varying the sensor annulus. See Table 1
28、for the selection of the piston according to the viscosity range.6.1.3 Measurement ChamberLocation within Oscillating Piston Viscometer where piston motion (through the liquid undertest) occurs due to an imposed electromagnetic field. See Fig. 1.6.1.4 ElectronicsCapable of controlling the electromag
29、netic field to propel and detect the travel time of the piston with adiscrimination of 0.01 s or better and uncertainty within 60.07 %. The travel time is calibrated to be between 0.4 s and 60 s, ata distance of 5 mm.6.1.5 Temperature Controlled JacketSufficient for maintaining measurement chamber t
30、emperature within 60.06C.6.1.6 Temperature Measuring DeviceIndustrial platinum resistance thermometer (IPRT) or equivalent sensor with a maximumpermissible error of 60.02C. It is recommended, that the temperature measuring device be verified with an independent,calibrated temperature probe at the te
31、st temperature.6.2 Temperature Regulation System:6.2.1 Any liquid bath or thermoelectric means for regulating the jacket temperature.6.2.2 The temperature control must be such that the temperature of the measurement chamber is held within 60.06C of thedesired measurement temperature.6.3 Sample Intro
32、duction MechanismA syringe, micropipette, or flow-through adapter for introducing between 3.2 mL and 5mL, inclusive by pressure, into the measurement chamber.5 The Oscillating Piston Viscometer is covered by a patent. Interested parties are invited to submit information regarding the identification
33、of an alternative to this patenteditem to the ASTM International headquarters. Your comments will receive careful consideration at a meeting of the responsible technical committee, which you may attend.6 The sole sources of supply for the apparatus known to the committee at this time is Cambridge Vi
34、scosity Inc., 101 Station Landing, Medford, MA 02155(). If you are aware of alternative suppliers, please provide this information to ASTM International Headquarters. Your comments will receivecareful consideration at a meeting of the responsible technical committee, which you may attend.FIG. 2 Visc
35、ometer with ElectronicsD7483 1337. Reagents and Materials7.1 Certified viscosity reference standards shall be certified by a laboratory that has been shown to meet the requirements ofISO/EC 17025 by independent assessment. Viscosity standards shall be traceable to master viscometer procedures descri
36、bed inPractice D2162.7.2 The uncertainty of the certified viscosity reference standard 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 published viscosity in accordance with Test Method D445 or e
37、quivalentmeans that is close to that of the liquids being tested at the test temperature. For example, if intended measurements are to be madefrom 5-25 mPas at 100C, then a reference oil viscosity of 15 mPas at 100C would be appropriate.7.3 Cleaning solvents miscible with the sample and chemically c
38、ompatible with the wetted viscometer components (such asalcohols, toluene, etc.). These wetted components are typically 316L and 430 Stainless Steel.7.4 Quality control (QC) liquid similar to 7.1, but with viscosity values internally certified as noted in 12.2.8. 8. Sampling, Samples, and Test Units
39、8.1 Ensure that the sample is homogenous. Engine sampling is generally specified in the test method, for example Test MethodD5967. When applicable, refer to Practice D4057 (manual) or Practice D4177 (automatic) for proper sampling techniques.9. Preparation of Apparatus9.1 Place the viscometer on a s
40、table surface.9.2 Operate the unit according to the procedure in Section 13.9.3 Verify calibration accuracy by testing a reference standard or QC liquid at the test temperature. Follow the procedure inSection 13.10. Calibration and Standardization10.1 Calibrate according to manufacturers instruction
41、s to obtain a calibration curve (using two test liquids with referencedviscosity values near, but within, the extremes of the piston range being used).TABLE 1 Viscosity Ranges of Oscillating Viscometer PistonsMinimum Viscosity (mPas ) Maximum Viscosity (mPas ) Piston Designation Nominal Piston Diame
42、ter (mm) Recommended Sample Volume(mL)0.02 2 SP20 7.87 3.2 - 50.25 5 SP50 7.83 3.2 - 50.5 10 SP11 7.81 3.2 - 51 20 SP21 7.76 3.5 - 52.5 50 SP51 7.68 3.5 - 55 100 SP12 7.62 3.5 - 510 200 SP22 7.54 3.5 - 525 500 SP52 7.34 3.5 - 550 1000 SP13 7.21 4.0 - 5100 2000 SP23 6.96 4.0 - 5250 5000 SP53 6.27 4.0
43、 5500 10000 SP14 6.05 4.0 - 51000 20000 SP24 5.72 4.0 - 5TABLE 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 SP50 7.83 3.250.5 10 SP11 7.
44、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 13410.2 Certified Viscosity Standards may be used as confirmatory
45、checks on the procedure in the laboratory. This procedure isoutlined in Section 13. If the dynamic viscosity result, at the calibration test point, does not agree with the certified value withinthe limits of precision in Section 16, each step in the procedure should be rechecked, as well as the temp
46、erature measuring deviceand viscometer calibration, to locate the source of error. If the source is not detected, consult the manufacturer.11. Sample Conditioning11.1 Shake all new and used oil samples using the following procedure.11.1.1 Ensure cap is tight on the container.11.1.2 Shake vigorously
47、by hand for 30 s. Wait 10 s, or longer 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 samples must beconveyed for analysis promptly following the shaking and dissipation procedure of step 11.1.2.12. Qual
48、ity Control/Quality Assurance (QC/QA)12.1 Confirm proper performance of the instrument and the test procedure by analyzing reference oil as QC sample.12.2 If suitable reference oil is not available, prepare a QC sample by replicate analyses of a batch of oil sample. Thenstatistically analyze the dat
49、a to assign a mean value and uncertainty limit to the sample.12.3 When QC/QA protocols are already established in the testing facility, these may be used to confirm the reliability of thetest result.12.4 When there is no QC/QA protocol established in the testing facility, guidance may be obtained from Practice D6792.13. Procedure13.1 Verify or set the temperature control settings, as tested with the control standard, so the viscometer temperature reads thedesired set point 60.06C while the
