1、ICS 17.060Viskosimetrie Messung der Viskositt mit demKugelfallviskosimeter nach HpplerIn keeping with current practice in standards published by the International Organization for Standardization(ISO), a comma has been used throughout as the decimal marker.ForewordThis standard has been prepared by
2、Technical Committee Viskosimetrie of the Normenausschuss Material-prfung (Material Testing Standards Committee).AmendmentsThis standard differs from the September 1978 edition as follows:a) The material has been changed for balls nos. 5 and 6.b) Methods of calibrating the viscometer and of determini
3、ng the uncertainty of measurement have beenincluded.c) The standard has been revised in form and content.Previous editionsSuppl to DIN 53655-1: 1947-12; DIN 53015: 1959-02, 1976-03, 1978-09.Ref. No. DIN 53015 : 2001-02English price group 11 Sales No. 011112.01DEUTSCHE NORM February 200153015Continue
4、d on pages 2 to 12. No part of this translation may be reproduced without the prior permission ofDIN Deutsches Institut fr Normung e.V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).ViscometryMeasurement of viscosity using the Hpp
5、lerfalling-ball viscometerTranslation by DIN-Sprachendienst.In case of doubt, the German-language original should be consulted as the authoritative text.1 ScopeThis standard specifies a method of determining the dynamic viscosity of Newtonian liquids using theHppler falling-ball viscometer, includin
6、g a method of calibrating the viscometer.2 Normative referencesThis standard incorporates, by dated or undated reference, provisions from other publications. Thesenormative references are cited at the appropriate places in the text, and the titles of the publications arelisted below. For dated refer
7、ences, subsequent amendments to or revisions of any of these publicationsapply to this standard only when incorporated in it by amendment or revision. For undated references, thelatest edition of the publication (including amendments) referred to applies.DIN 1319-1 Basic concepts in metrology Genera
8、l conceptsDIN 1319-3 Basic concepts in metrology Evaluating measurements of a single measurand and ex-pression of uncertaintyDIN 1342-1 Viscosity Rheological conceptsDIN 12785 Laboratory thermometers for particular applicationsDIN ISO 3585 Borosilicate glass 3.3 Properties (ISO 3585 : 1999)ISO 3507
9、: 1999 Laboratory glassware PyknometersSupersedes DIN 53015,September 1978 edition.All dimensions are in millimetres.Page 2DIN 53015 : 2001-02ISO 12058-1 : 1997 Plastics Determination of viscosity using a falling-ball viscometer Part 1: Inclined-tube methodISO 12185 : 1996 Crude petroleum and petrol
10、eum products Determination of density Oscillating U-tubemethodISO 15212-1 : 1998 Oscillation-type density meters Part 1: Laboratory instrumentsISO/TR 3666 : 1998 Viscosity of waterBS 188 : 1977 British Standard Methods for determination of the viscosity of liquids1 Deutsches Arzneimittelbuch (German
11、 Pharmacopoeia)2 Guide to the Expression of Uncertainty in Measurement. Geneva: International Organization for Standardi-zation, 1993.3 ConceptsThe following concept shall apply in addition to those defined in DIN 1319-1 and DIN 1342-1.Standard viscosity sampleA sample of a standard Newtonian liquid
12、 whose viscosity has been measured at one or more temperatures usingstandard viscometers, whose viscosity value(s) and their traceability to the national viscosity standard aredocumented, and which serves as a material measure for promulgating the unit of viscosity.4 Symbols, quantities and unitsTab
13、le 1: Symbols, quantities and unitsSymbol Quantity SI unit Further legal unitsd Ball diameter m mm, mD Difference between ball and liquid densities kg/m3g/cm3g Acceleration due to gravity at viscosity measurement site m/s2gAcceleration due to gravity at viscometer calibration site m/s2K Calibration
14、constant Pa . s . m3/(kg . s) mPa . s . cm3/(g . s)m Ball mass kg gmWWeighed value of ball mass kg gn Number of fall times in a measurement series ()2DsRelative variance of difference between ball and liquid densities()2KsRelative variance of calibration constant ()2NsRelative variance of viscosity
15、due to deviation of the viscometer position from the horizontal()2tsRelative variance of ball fall time ()2timersRelative variance for timer us Temperature measurement standard deviation C K()2hu,sRelative variance of viscosity due to uncertainty of temperature measurement2FrsVariance of liquid dens
16、ity kg2/m6g2/cm62KrsVariance of ball density kg2/m6g2/cm6()2KrsRelative variance of ball density t Ball fall time s t1Minimum fall time required for calculating the uncertainty s as in subclause 12.2 (cf. table 4)t2Minimum fall time for obtaining a reproducible s measurement(continued)Page 3DIN 5301
17、5 : 2001-025 Measurement rangeThis method is suitable for measuring dynamic viscosities ranging from 0,6 mPa . s to 250000 mPa . s attemperatures from 20 C to 120 C. To cover this range, use is made of six balls having different diameters,each ball covering part of the range (see table 2).NOTE 1: Th
18、e lower limit of 0,6 mPa . s is reached at the minimum fall time t2specified in table 3 if the densityof the liquid to be measured is 1,0 g/cm3or more.NOTE 2: If the materials used (e.g. seals, feed hoses) are suitable, it is quite possible to perform measurementsoutside the specified temperature ra
19、nge (40 C to 150 C). The temperature measured in the thermal jacketmay differ by more than specified in subclause 8.4 from the temperature of the sample in the fall tube andallowance shall be made for this in determining the uncertainty.Table 2: Viscometer ball diameters for an internal fall tube di
20、ameter of 15,94 mmBall no. MaterialDensityBallDeviation Calibration Viscosity(guidelinediameter,from constant (guide- measurementvalue), rKW,in mmcircularity, line value), K, in range,in g/cm3in mm mPa . s . cm3/g . s in mPa . s1 Borosilicate glass 2,4 15,81 t 0,01 t 0,0005 0,007 0,6 to 500102 Boros
21、ilicate glass 2,4 15,60 t 0,05 t 0,0005 0,09 9,0 to 501403 Ni/iron 8,1 15,60 t 0,05 t 0,001 0,09 40,0 to 507004 Ni/iron 8,1 15,20 t 0,1 t 0,001 0,7 150,0 to 050005 Ni/iron 8,1 14,00 t 0,5 t 0,001 7 1500,0 to 500006 Ni/iron 8,1 11,00 t 1 t 0,002 35 Above 7 5006 PrincipleThe time taken by a ball to tr
22、averse a distance delineated by marks (gauge length) under the influence of gravityis measured in an inclined cylindrical tube filled with the liquid to be examined.Symbol Quantity SI unit Further legal unitstmax, tminLongest and shortest ball fall times in a series of n single s measurementsuuUncer
23、tainty of temperature measurement C KUh, UnTemperature coefficient of dynamic or kinematic viscosity 1/K 1/ChuRelative uncertainty of viscosity measurement KruRelative uncertainty of ball density measurement KuRelative uncertainty for determination of calibration constant W Air buoyancy constant a C
24、oefficient of linear thermal expansion 1/K etRelative range of ball fall times in a series of measurements made using one viscometerh Dynamic viscosity Pa . s mPa . shNDynamic viscosity of a standard sample Pa . s mPa . shNuDynamic viscosity of a standard sample at calibration Pa . s mPa . stemperat
25、ureu Temperature C KuKCalibration temperature C KrFLiquid density kg/m3g/cm3rKBall density kg/m3g/cm3rKWGuideline value for ball density (for calculating air buoyancy kg/m3g/cm3correction)Table 1 (concluded)7 Theory of methodThe method uses the viscometer equation derived from Stokes law:()ggtK-= FK
26、rrh (1)the constants K and rKbeing determined by calibration (see clause 11).8 ApparatusThe following equipment shall be used.8.1 Hppler falling-ball viscometerThe viscometer (see figure 1) consists of a fall tube (2) containing the liquid to be measured and a ball (3) chosento suit the viscosity of
27、 the liquid. The tube is surrounded concentrically by a tubular jacket for thermal control(thermal jacket, for short) (1) mounted on a stand (4). The jacket and tube are linked by a pivoting spindle (5)that is perpendicular to the axis of the tube and is inclined at an angle of (10 t 1) to the horiz
28、ontal. To returnthe ball to the starting position, the tube and jacket assembly can be swivelled through 180 with respect tothe stand. In the starting position, the assembly is secured to the stand by a lock (6). The stand has three feet(7), with the height of two of them being adjustable by levelli
29、ng screws.A spirit level (8) having a maximum error of 0,2 is provided on the stand to ensure that the tube is at the correctangle with respect to the vertical.The temperature is measured by a replaceable thermometer (9) in the thermal jacket.The fall tube*) is a calibrated precision glass tube made
30、 of borosilicate glass 3.3 as in DIN ISO 3585 having acoefficient of linear thermal expansion of 3,3 . 106K1, with an internal diameter of 15,94 mm. In its centralsection the tube has an upper and a lower mark (M1and M2, respectively) that define the gauge length(100 t 1) mm), an identifying tube nu
31、mber and a longitudinal line or similar mark. It is to be inserted so that anarrow on the cover plate of the thermal jacket is aligned with the longitudinal line. The tube is sealed by twoplugs, the upper plug (10) containing a capillary joined to a hollow space. The plugs are intended to preventuna
32、cceptable variations in pressure and the ingress of air in the event of temperature fluctuations.The viscometer has six balls, each of which covers the part of the measurement range given in table 2. It isessential for them to have the same coefficient of linear thermal expansion as the tube (i.e. 3
33、,3 . 106K1) sincethe uncertainties will not otherwise be applicable.8.2 ThermometerEither calibrated (fully immersed) glass mercury thermometers or electrical thermometers can be used providedthat, when fully immersed, and the corrections specified on the calibration certificate are applied, they pe
34、rmitmeasurement of the temperature in the thermal jacket with an uncertainty, uu, of 0,03 C (cf. clause 12).Examples of suitable thermometers are DIN 12785 glass mercury thermometers designed to suit the Hpplerviscometer or platinum resistance thermometers of suitable design. If the temperature in t
35、he jacket is deter-mined with a greater uncertainty of measurement, allowance should be made for this in the uncertainty calcu-lation in subclause 12.2.The thermometer shall be protected against thermal radiation during the measurement.8.3 TimerThe timer shall be a stopwatch capable of being read to
36、 an accuracy of 0,01 s. It shall be recalibrated at intervalsdepending on its type and operating conditions, taking care to ensure that the relative uncertainty of measure-ment does not exceed 2 . 104.8.4 ThermostatThe thermostat used shall be an automatically controlled thermostatic bath connected
37、to the thermal jacket ofthe viscometer in a closed loop and shall ensure that the temperature in the jacket is maintained to within 0,02 Cfor temperatures from 10 C to 70 C (or to within 0,05 C for temperatures outside this range) while a seriesof measurements is being performed.NOTE: After the time
38、 specified for reaching steady-state conditions, the difference between the temperatureindicated in the jacket and the temperature in the tube will not exceed 0,01 C.*) Translators note. Term adopted from BS 188. Referred to as measurement tube in International StandardISO 12058-1.Page 4DIN 53015 :
39、2001-02Key to figure1 Thermal jacket2 Fall tube3 Ball4 Stand5 Pivoting spindle6 Lock7 Levelling screws8 Spirit level9 Thermometer10 Upper plugM1, M2MarksGauge lengthFigure 1: Example of a Hppler falling-ball viscometerPage 5DIN 53015 : 2001-028.5 Density measurementsDensities shall be measured with
40、equipment permitting the density of the liquids under examination to bedetermined with a relative uncertainty of measurement ofa) 5 . 104if glass balls andb) 1 . 103if metal ballsare used.NOTE: Examples of suitable equipment are oscillating density meters as in ISO 12185 and ISO 15212-1 orISO 3507 p
41、yknometers combined with a balance.9 SamplingA sample of about 40 ml will be needed for one viscometer filling. It shall be collected and pretreated asspecified in the requirements or standards relating to the liquid to be examined.10 Preparation10.1 Sample preparationIf the sample has been treated
42、as specified in clause 9, no further preparation will be necessary. However, high-viscosity liquids may be heated to facilitate transfer to the viscometer provided the viscosity of the liquid at thetemperature of measurement remains unaltered.NOTE: Non-Newtonian behaviour may be expected in the case
43、 of measurements made near the freezing pointsof liquids or their components.Unless specified, the sample shall be filtered only if the particles in the liquid could interfere with the measure-ment. In such cases, a note shall be included in the test report that also states the pore size of the filt
44、er used.Hazardous substances shall be handled in accordance with the relevant occupational safety regulations andthe regulations relating to waste disposal.10.2 Ball selectionThe fall times of the balls selected shall not be below the values in table 3.Table 3: Minimum fall timesMinimum fall times,B
45、all no. in secondst1t21 700 602 300 503 300 504 150 505303063In table 3, t1is the minimum fall time required for calculating the uncertainty as in subclause 12.2 (cf. table 4),while t2is the minimum fall time for obtaining a reproducible measurement. Fall times of less than t1will resultin systemati
46、c departures from equation (1) (i.e. an extension of transit time) that may amount to several per cent.A correction curve can be determined for every viscometer by using several liquids of known viscosities.10.3 Measuring the fall time10.3.1 Preparation of equipmentClean the viscometer balls, fall t
47、ube, end caps and plates, plugs and sealing rings with suitable liquids, the brushprovided being used for the tube. Prior to calibration use petroleum spirit that evaporates without residue (e.g.surgical spirit as specified in Deutsches Arzneimittelbuch for cleaning. After rinsing several times, dry
48、 in an ovenset to not more than 50 C.Ensure that the capillary in the plug is unobstructed.Protect the balls, fall tube, end caps and plates, plugs and sealing rings from dust prior to measurement.Insert the fall tube so that the arrow on the cover plate of the thermal jacket is aligned with the lon
49、gitudinal lineor the mark on the fall tube.10.3.2 ProcedureAlign the viscometer using the built-in spirit level, then transfer the sample to the fall tube as specified in theoperating manual for the viscometer. After allowing the temperature to stabilize for 30 minutes, remove theupper end cap again, then screw it back on tightly in order to establish pressure equilibrium. Ensure that thereis some air in the plug.Rotate the tube through 180 so that the ball falls
