1、Designation: D7279 14aStandard Test Method forKinematic Viscosity of Transparent and Opaque Liquids byAutomated Houillon Viscometer1This standard is issued under the fixed designation D7279; the number immediately following the designation indicates the year oforiginal adoption or, in the case of re
2、vision, 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 the kine-matic viscosity of transparent and opaque liq
3、uids; such as baseoils, formulated oils, diesel oil, biodiesel, biodiesel blends, andused lubricating oils using a Houillon viscometer in automatedmode.1.2 The range of kinematic viscosity capable of beingmeasured by this test method is from 2 mm2/s to 1500 mm2/s(see Fig. 1). The range is dependent
4、on the tube constantutilized. The temperature range that the apparatus is capable ofachieving is between 20 C and 150 C, inclusive. However,the precision has only been determined for the viscosity range;2mm2/s to 478 mm2/s at 40 C for base oils, formulated oils,diesel oil, biodiesel, and biodiesel b
5、lends; 3 mm2/s to106 mm2/s at 100 C for base oils and formulated oils;25 mm2/s to 150 mm2/s at 40 C and 5 mm2/s to 16 mm2/s at100 C for used lubricating oils. As indicated for the materialslisted in the precision section.1.3 The values stated in SI units are to be regarded asstandard. No other units
6、 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 safety and health practices and determine the applica-bility of regula
7、tory limitations prior to use. For specificwarning statements, see Section 6.2. Referenced Documents2.1 ASTM Standards:2D445 Test Method for Kinematic Viscosity of Transparentand Opaque Liquids (and Calculation of Dynamic Viscos-ity)D2162 Practice for Basic Calibration of Master Viscometersand Visco
8、sity Oil StandardsD4057 Practice for Manual Sampling of Petroleum andPetroleum ProductsD4177 Practice for Automatic Sampling of Petroleum andPetroleum ProductsD6299 Practice for Applying Statistical Quality Assuranceand Control Charting Techniques to Evaluate AnalyticalMeasurement System Performance
9、D6708 Practice for Statistical Assessment and Improvementof Expected Agreement Between Two Test Methods thatPurport to Measure the Same Property of a MaterialD6792 Practice for Quality System in Petroleum Productsand Lubricants Testing LaboratoriesE1137 Specification for Industrial Platinum Resistan
10、ce Ther-mometers2.2 ISO Standards:ISO 5725 Accuracy (Trueness and Precision) of Measure-ment Methods and Results3ISO/EC 17025 General Requirements for the Competence ofTesting and Calibration Laboratories32.3 NIST Standard:NIST Technical Note 1297 Guideline for Evaluating andExpressing the Uncertain
11、ty of NIST Measurement Re-sults43. Summary of Test Method3.1 The kinematic viscosity is determined by measuring thetime taken for a sample to fill a calibrated volume at a giventemperature. The specimen is introduced into the apparatus andthen flows into the viscometer tube which is equipped with tw
12、odetection cells. The specimen reaches the test temperature ofthe viscometer bath and when the leading edge of the specimenpasses in front of the first detection cell, the automatedinstrument starts the timing sequence. When the leading edgeof the specimen passes in front of the second detection cel
13、l, the1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility ofSubcommittee D02.07 on Flow Properties.Current edition approved Oct. 1, 2014. Published November 2014. Originallyapproved in 2006. Last previo
14、us edition approved in 2014 as D7279 14. DOI:10.1520/D7279-14A.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM websit
15、e.3Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org.4Available from National Institute of Standards and Technology (NIST), 100Bureau Dr., Stop 1070, Gaithersburg, MD 20899-1070, http:/www.nist.gov.*A Summary of Changes sect
16、ion appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1instrument stops timing the flow. The time interval thusmeasured allows the calculation of the kinematic viscosityusing a viscometer tube constant
17、determined earlier by calibra-tion with certified viscosity reference standards.3.2 The kinematic viscosity is calculated using the formula: 5 C 3t (1)where: = the kinematic viscosity in mm2/s,C = the viscometer tube constant in mm2/s, andt = the flow time in s measured during the test.4. Significan
18、ce and Use4.1 Many petroleum products and some non-petroleumproducts are used as lubricants in the equipment, and thecorrect operation of the equipment depends upon the appropri-ate viscosity of the lubricant being used. Additionally, theviscosity of many petroleum fuels is important for the estima-
19、tion of optimum storage, handling, and operational conditions.Thus, the accurate determination of viscosity is essential tomany product specifications.4.2 The viscosity of used oils is a commonly determinedparameter in the oil industry to assess the effect of engine wearon the lube oils used, as wel
20、l as the degradation of the engineparts during operation.4.3 The Houillon viscometer tube method offers automateddetermination of kinematic viscosity. Typically a sample vol-ume of less than 1 mL is required for the analysis.5. Apparatus5.1 Automated ViscometerThe system shall consist of thefollowin
21、g components:5.1.1 Viscometer Bath:5.1.1.1 Bath, to ensure optimal thermal equilibration of thesystem, the bath is filled with mineral or silicone oil andequipped with a stirring device.5.1.2 Temperature Regulation System, to control the bathtemperature to within 0.02 C.5.1.3 Houillon Viscometer Tub
22、es, made of glass with acalibrated volume which varies depending on the tube size (seeFig. 2). This technique allows the viscosity to be measuredover a wide range of values (see Fig. 1).5.1.4 Cleaning/Vacuum System, consisting of one or moresolvent reservoirs to transport the solvent(s) to the visco
23、metertubes, dry the viscometer tubes after the flushing cycle, toremove the sample, and for drainage of waste products.5.1.5 Automated Viscometer Control SystemSuitable elec-tronic processor capable of operating the apparatus, controllingthe operation of the timers, regulating the bath temperature,c
24、leaning the viscometer tubes, and recording and reporting theresults.5.1.6 PC-compatible Computer System, may be used fordata acquisition, as per manufacturers instructions.5.1.7 Temperature Measuring DevicesUse either cali-brated liquid-in-glass thermometers, of an accuracy after cor-rection of 60.
25、02 C or better, or other thermometric devicessuch as a digital contact thermometer as described in 5.1.7.1with equal or better accuracy.5.1.7.1 When using a digital contact thermometer (DCT) thefollowing shall apply: (1) The only acceptable sensors are aresistance temperature device (RTD), such as a
26、 platinumresistance thermometer (PRT) or a thermistor. (2) A minimumdisplay resolution of 0.01 C. (3) A combined (display andprobe) minimum accuracy of 60.02 C. (4) A response time ofless than6sasdefined in Specification E1137.(5) A drift ofless than 10 mK (0.01 C) per year. (6) Linearity of 10 mK o
27、verthe range of intended use. (7) The DCT shall have a report oftemperature calibration traceable to a national calibration ormetrology standards body issued by a competent calibrationlaboratory with demonstrated competency in temperature cali-bration. (8) The calibration report shall include data f
28、or theseries of test points which are appropriate for its intended use.NOTE 1Viscosity range of a Houillon tube is based on most practical flow time of 30 s to 200 s.FIG. 1 Houillon Viscometer Typical Viscosity Range of Tube ConstantsD7279 14a2(1) For a constant temperature bath employed in manualvi
29、scosity measurements, the probe shall be immersed at least100 mm below the liquid level of the bath but no less than threetimes the sensor element length. The end of the probe sheathshall not extend past the bottom of the viscometer.(2) It is preferable for the center of the sensing element tobe loc
30、ated at the same level as the lower half of the workingcapillary as long as the minimum immersion requirements aremet.(3) In the case of constant temperature baths used ininstruments for automatic viscosity determinations, the user isto contact the instrument manufacturer for the correct DCT thathas
31、 performance equivalence to that described here.5.1.8 Timing DevicesUse any timing device that is ca-pable of taking readings with a discrimination of 0.01 s orbetter with an accuracy within 60.07 % of the reading whentested over the minimum and maximum intervals of expectedflow times.5.1.9 Volume D
32、elivery Device, such as a micropipette,capable of delivering a sufficient volume of sample to theHouillon tube being used. (See Fig. 1 for approximate samplevolumes.)6. Reagents and Materials6.1 Certified viscosity reference standards shall be certifiedby a laboratory that has been shown to meet the
33、 requirementsof ISO/EC 17025 by independent assessment. The certifiedviscosity reference standards shall be traceable to masterviscometer procedures described in Test Method D2162.6.1.1 The uncertainty of the certified viscosity referencestandard shall be stated for each certified value (k =295%conf
34、idence). See ISO 5725 or NIST 1297.6.2 Non-chromium-containing, strongly oxidizing acidcleaning solution. (WarningNon-chromium-containing,strongly oxidizing acid cleaning solutions are highly corrosiveand potentially hazardous in contact with organic materials, butdo not contain chromium which has s
35、pecial disposal prob-lems.)6.3 Solvent(s) for cleaning, drying, reagent grade. Refer tomanufacturers recommendations. Filter before use if neces-sary. Typical solvent(s) include:6.3.1 Toluene. (WarningFlammable. Vapor harmful.)6.3.2 Petroleum spirit or naphtha. (WarningFlammable.Health hazard.)6.3.3
36、 Acetone. (WarningExtremely flammable. Healthhazard.)6.3.4 Heptane. (WarningFlammable. Health hazard.)6.4 Technical grade silicone oil or white oil of appropriateviscosity (for example, about 100 mm2/s 25 C or equiva-lent) to maintain the test temperature.7. Sampling7.1 Obtain a representative test
37、specimen in accordancewith Practice D4057 or Practice D4177.8. Preparation of Apparatus8.1 Place the automated viscometer on a stable and levelhorizontal surface. Make appropriate piping, drainage, andvacuum connections. Refer to the manufacturers instructions.8.2 If not already mounted, install the
38、 detection cells.A and B = sample reservoirC and D = calibrated volumemeasurement zoneE = bulbF = detection cellTube Filling Volume for a MeasurementThe filling volume is OK when:At the beginning of a measurement:Sample lower meniscus is on C (start timing)Sample upper meniscus should be below AAt t
39、he end of a measurement:Sample lower meniscus is on D (stop timing)Sample upper meniscus should be above BFIG. 2 Houillon Tube Schematic DiagramD7279 14a38.3 After installing and securing all viscometer tubes in thebath, fill the bath with appropriate amount of bath fluid (see6.4).8.4 Add the approp
40、riate amount of solvent(s) to the solventreservoir(s).8.5 Follow the manufacturers instructions for the operationof the instrument.8.6 Select a clean, dry, and calibrated viscometer tubehaving a range covering the estimated kinematic viscosity ofthe specimen to be tested, if known. The appropriate v
41、iscom-eter tube to use depends on the estimated viscosity of thesample to be tested. The calculation in 8.6.1 may be used todecide which tube to use.8.6.1 Using Eq 1, the viscometer tube should be chosen sothat its constant C falls between /200 C /30 to give flowtimes, T, between 30 s and 200 s.NOTE
42、 1In the interlaboratory study5conducted for the developmentof this test method, the flow times were between 30 s and 200 s.8.6.2 If a viscosity estimate is not known, a second analysismay be necessary using a different viscometer tube after a firsttrial analysis.9. Calibration9.1 Calibrate accordin
43、g to the manufacturers instructions.Calibrated tubes may be purchased but shall be verified as per9.4.9.2 Use certified viscosity reference standards (see 6.1).9.3 Refer to Section 10 for general operation of the auto-mated viscometer and to the manufacturers instructions.9.4 The determined kinemati
44、c viscosity should match thecertified value within 60.5 %. If it does not, then reanalyze thestandard. If the value is still out of range, then check all controlsystem settings for the viscometer tube, and recheck each stepin the procedure, including the temperature measuring device,and viscometer c
45、alibration to locate the source of error.NOTE 2The most common sources of error are caused by particles ofdust lodged in the capillary bore of the viscosity tube (particularly for usedoils) and temperature measurement errors. Modification of the cleaningconstants by increasing the number of cycles a
46、nd increasing the aspirationtime before and after passage of the solvent (see Section 11) may berequired.10. General Procedure for Kinematic Viscosity10.1 Set and maintain the automated viscometer bath at therequired test temperature.10.1.1 Thermometers, if used, shall be held in an uprightposition
47、under the same conditions of immersion as whencalibrated.10.2 Introduce a sufficient volume of sample to the Houillontube, using a volume delivery device (see 5.1.9) such as amicro-pipette. The specimen volume to be used is a function ofthe viscometer tube constant (see Fig. 1). Fig. 2 shows thecorr
48、ect specimen levels during a measurement.NOTE 3Use a volume delivery device that is capable of introducingthe entire specimen volume in one operation.10.3 Introduce the specimen into the viscometer tube. Startthe measurement sequence.10.4 The automated viscometer processing system willmeasure the fl
49、ow times, calculate the viscosity according to Eq1, and record the result.10.5 Start the cleaning sequence (see Section 11).10.6 Allow the viscometer tube to reach the bath tempera-ture (about 5 min) before performing a new measurement.NOTE 4In some units, the equilibration time required may be muchless than 5 min.11. Cleaning of Viscosity Tubes11.1 The viscometer tubes are cleaned by vacuuming thespecimen residue left in the viscometer tube followed by theuse of a solvent to remove any traces of the specimen on theviscometer tube walls. T
