1、Designation: D7279 16D7279 18Standard 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 cas
2、e 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 the kinematic viscosity of transparent and opaq
3、ue liquids; such as base oils,formulated oils, diesel oil, biodiesel, biodiesel blends, residual fuel oils, marine fuels, and used lubricating oils using a Houillonviscometer in automated mode.1.2 The range of kinematic viscosity capable of being measured by this test method is from 2 mm2/s to 2500
4、mm2/s (see Fig.1). The range is dependent on the tube constant utilized. The temperature range that the apparatus is capable of achieving isbetween 20 C and 150 C, inclusive. However, the precision has only been determined for the viscosity range; 2 mm2/s to478 mm2/s at 40 C for base oils, formulate
5、d oils, diesel oil, biodiesel, and biodiesel blends; 3 mm2/s to 106 mm2/s at 100 C forbase oils and formulated oils; 25 mm2/s to 150 mm2/s at 40 C and 5 mm2/s to 16 mm2/s at 100 C for used lubricating oils;25 mm2/s to 2500 mm2/s at 50 C and 6 mm2/s to 110 mm2/s at 100 C for residual fuels. As indica
6、ted for the materials listed inthe precision section.1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the resp
7、onsibilityof the user of this standard to establish appropriate safety safety, health, and healthenvironmental practices and determine theapplicability of regulatory limitations prior to use. For specific warning statements, see Section 6.1.5 This international standard was developed in accordance w
8、ith internationally recognized principles on standardizationestablished in the Decision on Principles for the Development of International Standards, Guides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards
9、: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 Practice for Automatic
10、Sampling of Petroleum and Petroleum ProductsD6299 Practice for Applying Statistical Quality Assurance and Control Charting Techniques to Evaluate Analytical Measure-ment System PerformanceD6300 Practice for Determination of Precision and Bias Data for Use in Test Methods for Petroleum Products and L
11、ubricantsD6708 Practice for Statistical Assessment and Improvement of Expected Agreement Between Two Test Methods that Purportto Measure the Same Property of a MaterialD6792 Practice for Quality Management Systems in Petroleum Products, Liquid Fuels, and Lubricants Testing LaboratoriesD7962 Practice
12、 for Determination of Minimum Immersion Depth and Assessment of Temperature Sensor Measurement DriftE563 Practice for Preparation and Use of an Ice-Point Bath as a Reference TemperatureE1137E644 Specification Test Methods for Testing Industrial Platinum Resistance ThermometersE1750 Guide for Use of
13、Water Triple Point CellsE2877 Guide for Digital Contact Thermometers1 This test method is under the jurisdiction ofASTM Committee D02 on Petroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility of SubcommitteeD02.07 on Flow Properties.Current edition approved June 1, 2016Jun
14、e 1, 2018. Published July 2016July 2018. Originally approved in 2006. Last previous edition approved in 20142016 asD7279 14a.D7279 16. DOI: 10.1520/D7279-16.10.1520/D7279-18.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For A
15、nnual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not
16、be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes section appears at the end
17、of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States12.2 ISO Standards:ISO 5725 Accuracy (Trueness and Precision) of Measurement Methods and Results3ISO/EC 17025 General Requirements for the Competence of Testing and Calibr
18、ation Laboratories32.3 NIST Standard:NIST Technical Note 1297 Guideline for Evaluating and Expressing the Uncertainty of NIST Measurement Results43. Summary of Test Method3.1 The kinematic viscosity is determined by measuring the time taken for a sample to fill a calibrated volume at a giventemperat
19、ure. The specimen is introduced into the apparatus and then flows into the viscometer tube which is equipped with twodetection cells.The specimen reaches the test temperature of the viscometer bath and when the leading edge of the specimen passesin front of the first detection cell, the automated in
20、strument starts the timing sequence. When the leading edge of the specimenpasses in front of the second detection cell, the instrument stops timing the flow. The time interval thus measured allows thecalculation of the kinematic viscosity using a viscometer tube constant determined earlier by calibr
21、ation with certified viscosityreference standards.3.2 The kinematic viscosity is calculated using the formula:5C 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. Significance and Use4.1 Many petroleum pro
22、ducts and some non-petroleum products are used as lubricants in the equipment, and the correctoperation of the equipment depends upon the appropriate viscosity of the lubricant being used.Additionally, the viscosity of manypetroleum fuels is important for the estimation of optimum storage, handling,
23、 and operational conditions. Thus, the accuratedetermination of viscosity is essential to many product specifications.4.2 The viscosity of used oils is a commonly determined parameter in the oil industry to assess the effect of engine wear onthe lube oils used, as well as the degradation of the engi
24、ne parts during operation.4.3 The Houillon viscometer tube method offers automated determination of kinematic viscosity. Typically a sample volume ofless than 1 mL is required for the analysis.3 Available from American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 1003
25、6, http:/www.ansi.org.4 Available from National Institute of Standards and Technology (NIST), 100 Bureau Dr., Stop 1070, Gaithersburg, MD 20899-1070, http:/www.nist.gov.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 V
26、iscosity Range of Tube ConstantsD7279 1825. Apparatus5.1 Automated ViscometerThe system shall consist of the following components:5.1.1 Viscometer Bath:5.1.1.1 Bath, to ensure optimal thermal equilibration of the system, the bath is filled with mineral or silicone oil and equippedwith a stirring dev
27、ice.5.1.2 Temperature Regulation System, to control the bath temperature to within 0.02 C.5.1.3 Houillon Viscometer Tubes, made of glass with a calibrated volume which varies depending on the tube size (see Fig. 2).This technique allows the viscosity to be measured over a wide range of values (see F
28、ig. 1).5.1.4 Cleaning/Vacuum System, consisting of one or more solvent reservoirs to transport the solvent(s) to the viscometer tubes,dry the viscometer tubes after the flushing cycle, to remove the sample, and for drainage of waste products.5.1.5 Automated Viscometer Control SystemSuitable electron
29、ic processor capable of operating the apparatus, controlling theoperation of the timers, regulating the bath temperature, cleaning the viscometer tubes, and recording and reporting the results.5.1.6 PC-compatible Computer System, may be used for data acquisition, as per manufacturers instructions.5.
30、1.7 Temperature Measuring DevicesUse either calibrated liquid-in-glass thermometers, of an accuracy after correction of60.02 C or better, or other thermometric devices such as a digital contact thermometer as described in 5.1.7.1 with equal or betteraccuracy.5.1.7.1 When using a digital contact ther
31、mometer (DCT) the following shall apply: (1) The only acceptable sensors are aresistance temperature device (RTD), such as a platinum resistance thermometer (PRT) or a thermistor. (2) A minimum displayresolution of 0.01 C. (3) A combined (display and probe) minimum accuracy of 60.02 C. (4) A respons
32、e time of less than 6 sas defined in Specification E1137. (5) A drift of less than 10 mK (0.01 C) per year. (6) Linearity of 10 mK over the range ofintended use. (7) The DCT shall have a report of temperature calibration traceable to a national calibration or metrology standardsbody issued by a comp
33、etent calibration laboratory with demonstrated competency in temperature calibration. (8) The calibrationreport shall include data for the series of test points which are appropriate for its intended use.(1) For a constant temperature bath employed in manual viscosity measurements, the probe shall b
34、e immersed at least 100 mmbelow the liquid level of the bath but no less than three times the sensor element length. The end of the probe sheath shall notextend past the bottom of the viscometer.(2) It is preferable for the center of the sensing element to be located at the same level as the lower h
35、alf of the working capillaryas long as the minimum immersion requirements are met.(3) In the case of constant temperature baths used in instruments for automatic viscosity determinations, the user is to contactthe instrument manufacturer for the correct DCT that has performance equivalence to that d
36、escribed here.5.1.7 Timing DevicesUse any timing device that is capable of taking readings with a discrimination of 0.01 s or better withan accuracy within 60.07 % of the reading when tested over the minimum and maximum intervals of expected flow times.5.1.8 Volume Delivery Device, such as a micropi
37、pette, capable of delivering a sufficient volume of sample to the Houillon tubebeing used. (See Fig. 1 for approximate sample volumes.)5.2 Temperature Measuring DevicesUse either calibrated liquid-in-glass thermometers, of an accuracy after correction of60.02 C or better, or other thermometric devic
38、es such as a digital contact thermometer as described in 5.2.1 with equal or betteraccuracy.5.2.1 Digital Contact Thermometer Requirements:Parameter RequirementNominal temperature rangeA 20 C to +150 CDisplay resolution 0.01 C minimumAccuracyB 20 mK (0.02 C)Sensor type Platinum Resistance Thermomete
39、r (PRT), thermistorSensor sheathC 7 mm OD maximumSensor lengthD Less than 18 mmImmersion depthE Less than 40 mm per Practice D7962Measurement DriftE less than 10 mK (0.01 C) per yearResponse timeF less than or equal to 8 s per footnote FCalibration error less than 10 mK (0.01 C) over the range of in
40、tended useCalibration range Consistent with temperature range of useD7279 183Calibration data Two data points when the “range of use” is less than 30 C. At least three datapoints when the “range of use” is 30 C to 90 C. At least four data points when“range of use” is greater than 90 C. When more tha
41、n 2 data points, they shall beevenly distributed over the calibration range. The calibration data is to be included incalibration report.A and B = sample reservoirC and D = calibrated volumemeasurement zoneE = bulbF = detection cellTube Filling Volume for a MeasurementThe filling volume is OK when:A
42、t the beginning of a measurement:Sample lower meniscus is on C (start timing)Sample upper meniscus should be below AAt the end of a measurement:Sample lower meniscus is on D (stop timing)Sample upper meniscus should be above BFIG. 2 Houillon Tube Schematic DiagramD7279 184Calibration report From a c
43、alibration laboratory with demonstrated competency in temperature calibra-tion which is traceable to a national calibration laboratory or metrology standardsbodyA The nominal temperature range may be different from the values shown provided the calibration and accuracy criteria are met.B Accuracy is
44、 the combined accuracy of the DCT unit, which is the display and sensor. See Guide E2877 for more information on selecting a DCT.C Sensor sheath is the tube that holds the sensing element.D The physical length of the temperature sensing element.E As determined by Practice D7962 or an equivalent proc
45、edure.F Response Time The time for a DCT to respond to a step change in temperature. The response time is 63.2 % of the step change time as determined per Section9 of Test Method E644. The step change evaluation begins at 20 C 5 C air to 77 C 5 C with water circulating at 0.9 m s 0.09 m s past the s
46、ensor.5.2.2 Measurement DriftThe drift in calibration should be checked periodically and at least once per year. This can beaccomplished using Practice D7962 or Test Methods E644. When a DCTs calibration drifts in one direction over several checksagainst a reference temperature, such as the ice poin
47、t, it may be an indication of deterioration of the DCT. The probe is to berecalibrated when the check value differs by more than the drift listed in 5.2.1 since the last probe calibration. See Practice E563,Test Methods E644, or Guide E1750 for more information regarding checking calibrations.5.2.3
48、It is preferable for the center of the sensing element to be located at the same level as the lower half of the workingcapillary as long as the minimum immersion requirements are met.6. Reagents and Materials6.1 Certified viscosity reference standards shall be certified by a laboratory that has been
49、 shown to meet the requirements ofISO/EC 17025 by independent assessment. The certified viscosity reference standards shall be traceable to master viscometerprocedures described in Test Method D2162.6.1.1 The uncertainty of the certified viscosity reference standard shall be stated for each certified value (k = 2 95 %confidence). See ISO 5725 or NIST 1297.6.2 Non-chromium-containing, strongly oxidizing acid cleaning solution. (WarningNon-chromium-containing, stronglyoxidizing acid cleaning solutions are highly corrosi
