Designation:D445–
09
Designation:71/1/97
British Standard2000:Part71:1990
Standard Test Method for
Kinematic Viscosity of Transparent and Opaque Liquids非线性薛定谔方程
(and Calculation of Dynamic Viscosity)1
This standard is issued under thefixed designation D445;the number immediately following the designation indicates the year of
original adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.A
superscript epsilon(´)indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the Department of Defense.
1.Scope*
1.1This test method specifies a procedure for the determi-nation of the kinematic viscosity,n,of liquid petroleum products,both transparent and opaque,by measuring the time for a volume of liquid toflow under gravity through a calibrated glass capillary viscometer.The dynamic viscosity,h, can be obtained by multiplying the kinematic viscosity,n,by the density,r,of the liquid.
N OTE1—For the measurement of the kinematic viscosity and viscosity of bitumens,see also Test Methods D2170and D2171.
N OTE2—ISO3104corresponds to Test Method D445.
1.2The result obtained from this test method is dependent upon the behavior of the sample and is intended for application to liquids for which primarily the shear stress and shear rates are proportional(Newtonianflow behavior).If,however,the viscosity varies significantly with the rate of shear,different results may be obtained from viscometers of different capillary diameters.The procedure and precision values for residual fuel oils,which under some conditions exhibit non-Newtonian behavior,have been included.
1.3The range of kinematic viscosities covered by this test method is from0.2to300000mm2/s(see Table A1.1)at all temperatures(see6.3and6.4).The precision has only been determined for those materials,kinematic viscosity ranges and temperatures as shown in the footnotes to the precision section.
1.4The values stated in SI units are to be regarded as standard.No other units of measurement are included in this standard.
1.5This standard does not purport to address all of the safety concerns,if any,associated with its use.It is the responsibility 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 Documents
2.1ASTM Standards:2
D446Specifications and Operating Instructions for Glass Capillary Kinematic Viscometers
D1193Specification for Reagent Water
D1217Test Method for Density and Relative Density (Specific Gravity)of Liquids by Bingham Pycnometer
D1480Test Method for Density and Relative Density (Specific Gravity)of Viscous Materials by Bingham Pyc-nometer
D1481Test Method for Density and Relative Density (Specific Gravity)of Viscous Materials by Lipkin Bicap-illary Pycnometer
D2162Practice for Basic Calibration of Master Viscom-eters and Viscosity Oil Standards
D2170Test Method for Kinematic Viscosity of Asphalts (Bitumens)
D2171Test Method for Viscosity of Asphalts by Vacuum Capillary Viscometer
D6071Test Method for Low Level Sodium in High Purity Water by Graphite Furnace Atomic Absorption Spectros-copy
D6074Guide for Characterizing Hydrocarbon Lubricant Base Oils
D6617Practice for Laboratory Bias Detection Using Single Test Result from Standard Material
E1Specification for ASTM Liquid-in-Glass Thermometers E77Test Method for Inspection and Verification of Ther-mometers
2.2ISO Standards:3
1This test method is under the jurisdiction of ASTM Committee D02on
Petroleum Products and Lubricants and is the direct responsibility of Subcommittee D02.07on Flow
Properties.
Current edition approved July1,2009.Published August2009.Originally approved in1937.Last previous edition approved in2006as D445–06.
In the IP,this test method is under the jurisdiction of the Standardization Committee.
2For referenced ASTM standards,visit the ASTM website,,or contact ASTM Customer Service at For Annual Book of ASTM Standards volume information,refer to the standard’s Document Summary page on the ASTM website.
3Available from American National Standards Institute(ANSI),25W.43rd St., 4th Floor,New York,NY10036.
*A Summary of Changes section appears at the end of this standard. Copyright©ASTM International,100Barr Harbor Drive,PO Box C700,West Conshohocken,PA19428-2959,United States.
ISO 3104Petroleum Products—Transparent and Opaque Liquids—Determination of Kinematic Viscosity and Cal-culation of Dynamic Viscosity
ISO 3105Glass Capillary Kinematic Viscometers—Specification and Operating Instructions
ISO 3696Water for Analytical Laboratory Use—Specification and Test Methods
ISO 5725Accuracy (trueness and precision)of measure-ment methods and results.
ISO 9000Quality Management and Quality Assurance Standards—Guidelines for Selection and Use
ISO 17025General Requirements for the Competence of Testing and Calibration Laboratories 2.3NIST Standards:4
NIST Technical Note 1297,Guideline for Evaluating and Expressing the Uncertainty of NIST Measurement Results NIST GMP 11
NIST Special Publication 819
3.Terminology
3.1Definitions of Terms Specific to This Standard:
3.1.1automated viscometer ,n —apparatus which,in part or in whole,has mechanized one or more of
the procedural steps indicated in Section 11or 12without changing the principle or technique of the basic manual apparatus.The essential ele-ments of the apparatus in respect to dimensions,design,and operational characteristics are the same as those of the manual method.
3.1.1.1Discussion —Automated viscometers have the capa-bility to mimic some operation of the test method while reducing or removing the need for manual intervention or interpretation.Apparatus which determine kinematic viscosity by physical techniques that are different than those used in this test method are not considered to be Automated Viscometers.3.1.2density ,n —the mass per unit volume of a substance at a given temperature.
3.1.3dynamic viscosity ,n —the ratio between the applied shear stress and rate of shear of a liquid.
3.1.3.1Discussion —It is sometimes called the coefficient of dynamic viscosity or,simply,viscosity.Thus dynamic viscos-ity is a measure of the resistance to flow or deformation of a liquid.
3.1.3.2Discussion —The term dynamic viscosity can also be used in a different context to denote a frequency-dependent quantity in which shear stress and shear rate have a sinusodial time dependence.
3.1.4kinematic viscosity ,n —the resistance to flow of a fluid under gravity.
3.1.
4.1Discussion —For gravity flow under a given hydro-static head,the pressure head of a liquid is proportional to its density,r .For any particular viscometer,the time of flow of a fixed volume of fluid is directly proportional to its kinematic viscosity,n ,where n =h /r ,and h is the dynamic viscosity coefficient.
4.Summary of Test Method
4.1The time is measured for a fixed volume of liquid to flow under gravity through the capillary of a calibrated viscometer under a reproducible driving head and at a closely controlled and known temperature.The kinematic viscosity (determined value)is the product of the measured flow time and the calibration constant of the viscometer.Two such determinations are needed from which to calculate a kinematic viscosity result that is the average of two acceptable deter-mined values.
韦伯分布
5.Significance and Use
5.1Many petroleum products,and some non-petroleum materials,are used as lubricants,and the corr
ect operation of the equipment depends upon the appropriate viscosity of the liquid being used.In addition,the viscosity of many petroleum fuels is important for the estimation of optimum storage,handling,and operational conditions.Thus,the accurate deter-mination of viscosity is essential to many product specifica-tions.
6.Apparatus
6.1Viscometers —Use only calibrated viscometers of the glass capillary type,capable of being used to determine kinematic viscosity within the limits of the precision given in the precision section.
6.1.1Viscometers listed in Table A1.1,whose specifications meet those given in Specifications D 446and in ISO 3105meet these requirements.It is not intended to restrict this test method to the use of only those viscometers listed in Table A1.1.Annex A1gives further guidance.
热与冷
6.1.2Automated Viscometers —Automated apparatus may be used as long as they mimic the physical conditions,operations or processes of the manual apparatus.Any viscom-eter,temperature measuring device,temperature control,tem-perature controlled bath or timing device incorporated in the automated apparatus shall conform to the specification for these components as stated in Section 6of this test method.Flow times of less than 200s are permitted,however,a kinetic energy cor
rection shall be applied in accordance with Section 7on Kinematic Viscosity Calculation of Specifications D 446.The kinetic energy correction shall not exceed 3.0%of the measured viscosity.The automated apparatus shall be capable of determining kinematic viscosity of a certified viscosity reference standard within the limits stated in 9.2.1and Section 1
7.The precision shall be of statistical equivalence to,or better (has less variability)than the manual apparatus.
安置房
建设N OTE 3—Precision and bias of kinematic viscosity measurements for flow times of less than 200s has not been determined.The precision stated in Section 17is not know to be valid for kinematic viscosity measure-ments with flow times less than 200s.
6.2Viscometer Holders —Use viscometer holders to enable all viscometers which have the upper meniscus directly above the lower meniscus to be suspended vertically within 1°in all directions.Those viscometers whose upper meniscus is offset from directly above the lower meniscus shall be suspended vertically within 0.3°in all directions (see Specifications D 446and ISO 3105).
4
Available from National Institute of Standards and Technology (NIST),100Bureau Dr.,Stop 3460,Gaithersburg,MD
20899-3460.
6.2.1Viscometers shall be mounted in the constant tempera-ture bath in the same manner as when calibrated and stated on the certificate of calibration.See Specifications D446,see Operating Instructions in Annexes A1–A3.For those viscom-eters which have Tube L(see Specifications D446)held vertical,vertical alignment shall be confirmed by using(1)a holder ensured to hold Tube L vertical,or(2)a bubble level mounted on a rod designed tofit into Tube L,or(3)a plumb line suspended from the center of Tube L,or(4)other internal means of support provided in the constant temperature bath.
6.3Temperature-Controlled Bath—Use a transparent liquid bath of sufficient depth such,that at no time during the measurement offlow time,any portion of the sample in the viscometer is less than20mm below the surface of the bath liquid or less than20mm above the bottom of the bath.
6.3.1Temperature Control—For each series offlow time measurements,the temperature control of the bath liquid shall be such that within the range from15to100°C,the tempera-ture of the bath medium does not vary by more than60.02°C of the selected temperature over the length of the viscometer, or between the position of each viscometer,or at the location of the thermometer.For temperatures outside this range,the deviation from the desired temperature must not exceed 60.05°C.
6.4Temperature Measuring Device in the Range from0to 100°C—Use either calibrated liquid-in-glass thermometers (Annex A2)of an accuracy after correction of60.02°C or better,or any other thermometric device of equal or better accuracy.
6.4.1If calibrated liquid-in-glass thermometers are used,the use of two thermometers is recommended.The two thermom-eters shall agree within0.04°C.
6.4.2Outside the range from0to100°C,use either cali-brated liquid-in-glass thermometers of an accuracy after cor-rection of60.05°C or better,or any other thermometric device of equal or better accuracy.When two temperature measuring devices are used in the same bath,they shall agree within 60.1°C.
6.4.3When using liquid-in-glass thermometers,such as those in Table A2.1,use a magnifying device to read the thermometer to the nearest1⁄5division(for example,0.01°C or 0.02°F)to ensure that the required test temperature and temperature control capabilities are met(see10.1).It is recommended that thermometer readings(and any corrections supplied on the certificates of calibrations for the thermom-eters)be recorded on a periodic basis to demonstrate compli-ance with the test method requirements.This information can be quite useful,especially when investigating issues or causes relating to testing accuracy and precision.
6.5Timing Device—Use any timing device that is capable of taking readings with a discrimination of0.1s or better and has an accuracy within60.07%(see Annex A3)of the reading when tested over the minimum and maximum intervals of expectedflow times.
6.5.1Electrical timing devices may be used if the current frequency is controlled to an accuracy of0.05%or better. Alternating currents,as provided by some public power sys-tems,are intermittently rather than continuously controlled.When used to actuate electrical timing devices,such control can cause large errors in kinematic viscosityflow time mea-surements.
7.Reagents and Materials
7.1Chromic Acid Cleaning Solution,or a nonchromium-containing,strongly oxidizing acid cleaning solution. (Warning—Chromic acid is a health hazard.It is toxic,a recognized carcinogen,highly corrosive,and potentially haz-ardous in contact with organic materials.If used,wear a full face-shield and full-length protective clothing including suit-able gloves.Avoid breathing vapor.Dispose of used chromic acid carefully as it remains hazardous.Nonchromium-containing,strongly oxidizing acid cleaning solutions are also highly corrosive and potentially hazardous in contact with organic materials,but do not contain chromium which has special disposal problems.)
7.2Sample Solvent,completely miscible with the sample. Filter before use.
7.2.1For most samples a volatile petroleum spirit or naph-tha is suitable.For residual fuels,a prewash with an aromatic solvent such as toluene or xylene may be necessary to remove asphaltenic material.
7.3Drying Solvent,a volatile solvent miscible with the sample solvent(see7.2)and water(see7.4).Filter before use.
7.3.1Acetone is suitable.(Warning—Extremelyflam-mable.)
7.4Water,deionized or distilled and conforming to Speci-fication D1193or Grade3of ISO3696.Filter before use. 8.Certified Viscosity Reference Standardsmaxplus2下载
8.1Certified viscosity reference standards shall be certified by a laboratory that has been shown to meet the requirements of ISO17025by independent assessment.Viscosity standards shall be traceable to master viscometer procedures described in Test Method D2162.
8.2The uncertainty of the certified viscosity reference standard shall be stated for each certified value(k=2,95% confidence).See ISO5725or NIST1297.
9.Calibration and Verification
9.1Viscometers—Use only calibrated viscometers,ther-mometers,and timers as described in Section6.
9.2Certified Viscosity Reference Standards(Table A1.2)—These are for use as confirmatory checks on the procedure in the laboratory.
9.2.1If the determined kinematic viscosity does not agree within the acceptable tolerance band,as calculated from Annex A4,of the certified value,recheck each step in the procedure, including thermo
meter and viscometer calibration,to locate the source of error.Annex A1gives details of standards available. N OTE4—In previous issues of Test Method D445,limits of60.35%of the certified value have been used.The data to support the limit of 60.35%cannot be verified.Annex A4provides instructions on how to determine the tolerance band.The tolerance band combines both the uncertainty of the certified viscosity reference standard as well as the uncertainty of the laboratory using the certified viscosity reference
standard.
9.2.1.1As an alternative to the calculation in Annex A4,the approximate tolerance bands in Table 1may be used.
9.2.2The most common sources of error are caused by particles of dust lodged in the capillary bore and temperature measurement errors.It must be appreciated that a correct result obtained on a standard oil does not preclude the possibility of a counterbalancing combination of the possible sources of error.
9.3The calibration constant,C ,is dependent upon the gravitational acceleration at the place of calibration and this must,therefore,be supplied by the standardization laboratory together with the instrument constant.Where the acceleration of gravity,g ,differs by more that 0.1%,correct the calibration constant as follows:
C 25~g 2/g 1!3C 1
(1)
where the subscripts 1and 2indicate,respectively,the standardization laboratory and the testing laboratory.10.General Procedure for Kinematic Viscosity
10.1Adjust and maintain the viscometer bath at the required test temperature within the limits given in 6.3.1taking account of the conditions given in Annex A2and of the corrections supplied on the certi
ficates of calibration for the thermometers.10.1.1Thermometers shall be held in an upright position under the same conditions of immersion as when calibrated.10.1.2In order to obtain the most reliable temperature measurement,it is recommended that two thermometers with valid calibration certificates be used (see 6.4).
10.1.3They should be viewed with a lens assembly giving approximately five times magnification and be arranged to eliminate parallax errors.
10.2Select a clean,dry,calibrated viscometer having a range covering the estimated kinematic viscosity (that is,a wide capillary for a very viscous liquid and a narrower capillary for a more fluid liquid).The flow time for manual viscometers shall not be less than 200s or the longer time noted in Specifications D 446.Flow times of less than 200s are permitted for automated viscometers,provided they meet the requirements of 6.1.2.
10.2.1The specific details of operation vary for the different types of viscometers listed in Table A1.1.The operating instructions for the different types of viscometers are given in Specifications D 446.
中等发达国家10.2.2When the test temperature is below the dew point,fill the viscometer in the normal manner as r
equired in 11.1.To ensure that moisture does not condense or freeze on the walls
of the capillary,draw the test portion into the working capillary and timing bulb,place rubber stoppers into the tubes to hold the test portion in place,and insert the viscometer into the bath.After insertion,allow the viscometer to reach bath temperature,and the remove the stoppers.When performing manual viscos-ity determinations,do not use those viscometers which cannot be removed from the constant temperature bath for charging the sample portion.
10.2.2.1The use of loosely packed drying tubes affixed to the open ends of the viscometer is permitted,but not required.If used,the drying tubes shall fit the design of the viscometer and not restrict the flow of the sample by pressures created in the instrument.
10.2.3Viscometers used for silicone fluids,fluorocarbons,and other liquids which are difficult to remove by the use of a cleaning agent,shall be reserved for the exclusive use of those fluids except during their calibration.Subject such viscometers to calibration checks at frequent intervals.The solvent wash-ings from these viscometers shall not be used for the cleaning of other viscometers.
11.Procedure for Transparent Liquids
11.1Charge the viscometer in the manner dictated by the design of the instrument,this operation being in conformity with that employed when the instrument was calibrated.If the sample is thought or known to contain fibers or solid particles,filter through a 75µm screen,either prior to or during charging (see Specifications D 446).
N OTE 5—To minimize the potential of particles passing through the filter from aggregating,it is recommended that the time lapse between filtering and charging be kept to a minimum.
11.1.1In general,the viscometers used for transparent liquids are of the type listed in Table A1.1,A and B.
11.1.2With certain products which exhibit gel-like behav-ior,exercise care that flow time measurements are made at sufficiently high temperatures for such materials to flow freely,so that similar kinematic viscosity results are obtained in viscometers of different capillary diameters.
11.1.3Allow the charged viscometer to remain in the bath long enough to reach the test temperature.Where one bath is used to accommodate several viscometers,never add or with-draw,or clean a viscometer while any other viscometer is in use for measuring a flow time.
11.1.4Because this time will vary for different instruments,for different temperatures,and for different kinematic viscosi-ties,establish a safe equilibrium time by trial.
11.1.4.1Thirty minutes should be sufficient except for the highest kinematic viscosities.
11.1.5Where the design of the viscometer requires it,adjust the volume of the sample to the mark after the sample has reached temperature equilibrium.
11.2Use suction (if the sample contains no volatile con-stituents)or pressure to adjust the head level of the test sample to a position in the capillary arm of the instrument about 7mm above the first timing mark,unless any other value is stated in the operating instructions for the viscometer.With the sample flowing freely,measure,in seconds to within 0.1s,the time required for the meniscus to pass from the first to the second
TABLE 1Approximate Tolerance Bands
N OTE —The tolerance bands were determined using Practice D 6617.The calculation is documented in Research Report RR:D02–1498.A
Viscosity of Reference Material,mm 2/s Tolerance Band <10
60.30%10to 10060.32%100to 100060.36%1000to 1000060.42%10000to 10000060.54%>100000
60.73%
A
Supporting data have been filed at ASTM International Headquarters and may be obtained by requesting Research Report RR:
D02–1498.
timing mark.If thisflow time is less than the specified minimum(see10.2),select a viscometer with a capillary of smaller diameter and repeat the operation.
11.2.1Repeat the procedure described in11.2to make a second measurement offlow time.Record both measurements.
11.2.2From the two measurements offlow time,calculate two determined values of kinematic viscosity.
11.2.3If the two determined values of kinematic viscosity calculated from theflow time measurements agree within the stated determinabilityfigure(see17.1.1)for the product,use the average of these determined values to calculate the kine-matic viscosity result to be reported.Record the result.If not, repeat the measurements offlow times after a thorough cleaning and drying of the viscometers andfiltering(where required,see11.1)of the sample until the calculated kinematic viscosity determinations agree with the stated determinability.
11.2.4If the material or temperature,or both,is not listed in 17.1.1,use1.5%as an estimate of the determinability.
12.Procedure for Opaque Liquids
12.1For steam-refined cylinder oils and black lubricating oils,proceed to12.3ensuring a thoroughly representative sample is used.The kinematic viscosity of residual fuel oils and similar waxy products can be affected by the previous thermal history and the following procedure described in 12.1.1-12.2.2shall be followed to minimize this.
12.1.1In general,the viscometers used for opaque liquids are of the reverse-flow type listed in Table A1.1,C.
12.1.2Heat in the original container,in an oven,at606 2°C for1h.
12.1.3Thoroughly stir the sample with a suitable rod of sufficient length to reach the bottom of the container.Continue stirring until there is no sludge or wax adhering to the rod.
12.1.4Recap the container tightly and shake vigorously for 1min to complete the mixing.
12.1.4.1With samples of a very waxy nature or oils of high kinematic viscosity,it may be necessary to increase the heating temperature above60°C to achieve proper mixing.The sample should be sufficientlyfluid for ease of stirring and shaking.
12.2Immediately after completing12.1.4,pour sufficient sample tofill two viscometers into a100-mL glassflask and loosely stopper.
12.2.1Immerse theflask in a bath of boiling water for30 min.(Warning—Exercise care as vigorous boil-over can occur when opaque liquids which contain high levels of water are heated to high temperatures.)
12.2.2Remove theflask from the bath,stopper tightly,and shake for60s.
12.3Two determinations of the kinematic viscosity of the test material are required.For those viscometers that require a complete cleaning after eachflow time measurement,two viscometers may be used.A single viscometer in which an immediate,repeatflow time measurement can be made without cleaning may also be used for the two measurements offlow time and calculation of kinematic viscosity.Charge two vis-cometers in the manner dictated by the design of the instru-ment.For example,for the cross-arm or the BS U-tube viscometers for opaque liquids,filter the sample through a 75-µmfilter into two viscometers previously placed in the bath.For samples subjected to heat treatment,use a preheatedfilter to prevent the sample coagulating during thefiltration.
12.3.1Viscometers which are charged before being inserted into the bath may need to be preheated in an oven prior to charging the sample.This is to ensure that the sample will not be cooled below test temperature.
12.3.2After10min,adjust the volume of the sample(where the design of the viscometer requires)to coincide with the filling marks as in the viscometer specifications(see Specifi-cations D446).
12.3.3Allow the charged viscometers enough time to reach the test temperature(see12.3.1).Where o
ne bath is used to accommodate several viscometers,never add or withdraw,or clean a viscometer while any other viscometer is in use for measuringflow time.
12.4With the sampleflowing freely,measure in seconds to within0.1s,the time required for the advancing ring of contact to pass from thefirst timing mark to the second.Record the measurement.
12.4.1In the case of samples requiring heat treatment described in12.1through12.2.1,complete the measurements offlow time within1h of completing12.2.2.Record the measuredflow times.
12.5Calculate kinematic viscosity,n,in mm2/s,from each measuredflow time.Regard these as two determined values of kinematic viscosity.
12.5.1For residual fuel oils,if the two determined values of kinematic viscosity agree within the stated determinability figure(see17.1.1),use the average of these determined values to calculate the kinematic viscosity result to be reported. Record the result.If the calculated kinematic viscosities do not agree,repeat the measurements offlow times after thorough cleaning and drying of the viscometers andfiltering of the sample.If the material or temperature,or both,is not listed in 17.1.1,for temperatures between15and100°C use as an estimate of the determinability1.0%,and1.5%for tempera-tures outside this range;it must be realized that these materials can be non-Newtonian,and
can contain solids which can come out of solution as theflow time is being measured.
13.Cleaning of Viscometer
13.1Between successive determinations of kinematic vis-cosity,clean the viscometer thoroughly by several rinsings with the sample solvent,followed by the drying solvent(see 7.3).Dry the tube by passing a slow stream offiltered dry air through the viscometer for2min or until the last trace of solvent is removed.
13.2Periodically clean the viscometer with the cleaning solution(Warning—see7.1),for several hours to remove residual traces of organic deposits,rinse thoroughly with water (7.4)and drying solvent(see7.3),and dry withfiltered dry air or a vacuum line.Remove any inorganic deposits by hydro-chloric acid treatment before the use of cleaning acid,particu-larly if the presence of barium salts is suspected.(Warning—It is essential that alkaline cleaning solutions are not used as changes in the viscometer calibration can
occur.)
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