ASTM D6080-2012a red 7889 Standard Practice for Defining the Viscosity Characteristics of Hydraulic Fluids《液压流体粘滞特性定义的标准实施规程》.pdf

1、Designation: D6080 12D6080 12aStandard Practice forDefining the Viscosity Characteristics of Hydraulic Fluids1This standard is issued under the fixed designation D6080; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of la

2、st 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 practice covers all hydraulic fluids based either on petroleum, synthetic, or naturally-occurring base stocks. It

3、is notintended for water-containing hydraulic fluids.1.2 For determination of viscosities at low temperature, this practice uses millipascalsecond (mPas) as the unit of viscosity.For reference, 1 mPas is equivalent to 1 centipoise (cP). For determination of viscosities at high temperature, this prac

4、tice usesmillimetre squared per second (mm2/s) as the unit of kinematic viscosity. For reference, 1 mm2/s is equivalent to 1 centistoke (cSt).1.3 This practice is applicable to fluids ranging in kinematic viscosity from about 4 to 150 mm2/s as measured at a referencetemperature of 40C and to tempera

5、tures from 50 to +16C for a fluid viscosity of 750 mPas.NOTE 1Fluids of lesser or greater viscosity than the range described in 1.3 are seldom used as hydraulic fluids. Any mathematical extrapolation ofthe system to either higher or lower viscosity grades may not be appropriate. Any need to expand t

6、he system should be evaluated on its own merit.1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.2. Referenced Documents2.1 ASTM Standards:2D445 Test Method for Kinematic Viscosity of Transparent and Opaque Liquids (and Calc

7、ulation of Dynamic Viscosity)D2270 Practice for Calculating Viscosity Index from Kinematic Viscosity at 40 and 100CD2422 Classification of Industrial Fluid Lubricants by Viscosity SystemD2983 Test Method for Low-Temperature Viscosity of Lubricants Measured by Brookfield ViscometerD5621 Test Method f

8、or Sonic Shear Stability of Hydraulic FluidsE29 Practice for Using Significant Digits in Test Data to Determine Conformance with Specifications2.2 Society of Automotive Engineers (SAE) Standards:3J300 Engine Oil Viscosity ClassificationJ306 Axle and Manual Transmission Lubricant Viscosity Classifica

9、tion3. Terminology3.1 Definitions:3.1.1 density, nthe mass per unit volume.3.1.1 hydraulic fluid, na fluidliquid used in hydraulic systems for transmitting lubrication and transmission of power.3.1.3 in-service viscosity, nthe viscosity of fluid during operation of a hydraulic pump or circuit compon

10、ents.3.1.2 kinematic viscosity, nthe ratio of the dynamic viscosity to the density of a liquid.3.1.2.1 DiscussionKinematic For gravity flow under a given hydrostatic head, the pressure head of a liquid is proportional to its density. Therefore,kinematic viscosity is a measure of the resistance to fl

11、ow of a liquid under gravity.1 This practice is under the jurisdiction of ASTM Committee D02 on Petroleum Products and Lubricants and is the direct responsibility of Subcommittee D02.N0.10 onSpecifications.Current edition approved June 1, 2012Nov. 1, 2012. Published August 2012February 2013. Origina

12、lly approved in 1997. Last previous edition approved in 20102012 asD608010.12. DOI: 10.1520/D6080-12.10.1520/D6080-12A.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 t

13、o the standards Document Summary page on the ASTM website.3 Available from Society of Automotive Engineers (SAE), 400 Commonwealth Dr., Warrendale, PA 15096-0001, http:/www.sae.org.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of wha

14、t 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 versionof the standard as published by ASTM is to be considered the

15、 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 States13.1.3 Newtonian oil or fluid, na an oil or fluid that at a given temperature exhibits a constant visco

16、sity at all shear rates orshear stresses.3.1.4 non-Newtonian oil or fluid, na an oil or fluid that at a given temperature exhibits a viscosity that varies with changingshear stress or shear rate.3.1.5 shear degradation, nthe decrease in molecular weight of a polymeric thickener (VI improver) as a re

17、sult of exposureto high shear stress.3.1.6 shear rate, nthe velocity gradient in fluid flow.3.1.7 shear stability, nthe resistance of a polymer-thickened fluid to shear degradation.3.1.8 shear stress, nthe motivating force per unit area for fluid flow.3.1.9 viscosity, nthe ratio between the applied

18、shear stress and shear rate.the rate of shear.3.1.9.1 DiscussionViscosity is sometimes called the coefficient of dynamic viscosity. This coefficient is a measure of the resistance to flow of theliquid.3.1.10 viscosity index (VI), nan arbitrary number used to characterize the variation of the kinemat

19、ic viscosity of a fluid withtemperature.3.2 Definitions of Terms Specific to This Standard:3.2.1 in-service viscosity, nthe viscosity of fluid during operation of a hydraulic pump or circuit components.4. Summary of Practice4.1 High VI hydraulic fluids often contain high molecular weight thickeners,

20、 called viscosity index (VI) improvers, whichimpart non-Newtonian characteristics to the fluid. These polymers may shear degrade with use, and reduce the in-service viscosityof the fluids.4.2 This practice provides uniform guidelines for characterizing oils in terms of both their high and low temper

21、ature viscositiesbefore and after exposure to high shear stress.4.2.1 Since the performance of fluids at temperatures higher than 40C is determined in the worst case, that is, most severesituation, by the sheared oil viscosity, the viscosity and viscosity index used to characterize fluids in this pr

22、actice are those of thesheared fluid.4.2.2 This practice classifies oils at low temperature by their new oil properties. Low temperature viscosities do not decreasegreatly, if at all, with polymer shear degradation. Furthermore, this approach ensures that the fluid will be properly classified undert

23、he worst-case conditions, that is, when the fluid is new.4.3 This practice may be used with either Newtonian or non-Newtonian hydraulic fluids. This provides the user with a morereasonable basis to compare fluids than previous practices.5. Significance and Use5.1 The purpose of this practice is to e

24、stablish viscosity designations derived from viscosities measured by test methods whichhave a meaningful relationship to hydraulic fluid performance. This permits lubricant suppliers, lubricant users, and equipmentdesigners to have a uniform and common basis for designating, specifying, or selecting

25、 the viscosity characteristics of hydraulicfluids.5.2 This practice is not intended to be a replacement for Classification D2422. Rather, it is an enhancement intended to providea better description of the viscosity characteristics of lubricants used as hydraulic fluids.5.3 This practice implies no

26、evaluation of hydraulic oil quality other than its viscosity and shear stability under the conditionsspecified.5.4 While it is not intended for other functional fluids, this practice may be useful in high-shear-stress applications whereviscosity index (VI) improvers are used to extend the useful ope

27、rating temperature range of the fluid.5.5 This practice does not apply to other lubricants for which viscosity classification systems already exist, for example, SAEJ300 for automotive engine oils and SAE J306 for axle and manual transmission lubricants.6. Procedure6.1 The low temperature viscosity

28、grade of a fluid is based on the viscosity of new oil measured using a Brookfield viscometer,Test Method D2983.D6080 12a26.1.1 The viscosity shall be interpolated from measurements at three temperatures spanning the temperature at which theviscosity is 750 mPas. A smooth graph of these data (log vis

29、cosity versus temperature) determines the temperature at which theoil has a viscosity of 750 mPas.6.1.2 The temperature determined in 6.1.1 shall be rounded to a whole number in accordance with Practice E29.6.1.3 The low temperature viscosity grade is determined by matching the temperature determine

30、d in 6.1.2 with the requirementsshown in Table 1.6.2 The high temperature viscosity designation of a fluid is the 40C kinematic viscosity (Test Method D445) of a fluid whichhas been sheared using Test Method D5621.6.2.1 The kinematic viscosity determined in 6.2 shall be rounded to a whole number in

31、accordance with Practice E29.6.2.2 For a fluid known to contain no polymeric components which will shear degrade, the high temperature viscositydesignation is the 40C kinematic viscosity (Test Method D445) of the new fluid, rounded per 6.2.1.6.2.3 If the 40C kinematic viscosity from 6.2.1 fails to m

32、eet the same designation consistently (for example, it varies becauseof spread in base stock or component specifications, or variability in kinematic viscosity or shear stability measurements), thelower designation must be used to ensure conformance with 6.5 below.6.3 The viscosity index designation

33、 of the fluid is based on the viscosity index as determined using Practice D2270 on fluidwhich has been sheared using Test Method D5621.6.3.1 The viscosity index determined in 6.3 shall be rounded to the nearest ten units in accordance with Practice E29. This valueis the viscosity index designation.

34、6.3.2 For fluids which do not contain polymeric components, the viscosity index is determined on the new fluid using PracticeD2270. The viscosity index designation for the fluid is established by rounding this viscosity index to the nearest ten units inaccordance with Practice E29.NOTE 2The guidelin

35、es for rounding viscosity in 6.2.1 and 6.2.2 and viscosity index in 6.3.1 and 6.3.2 are specific to this practice and should not beconfused with the larger number of significant figures that can be reported when Test Methods D445 and D2270 are used for other purposes.6.3.3 If the viscosity index fai

36、ls to meet the same designation consistently, that is, it varies between the lower values for onedesignation and the higher values for the next lower designation (for example, it varies because of spread in base stock orcomponent specifications, or variability in kinematic viscosity or shear stabili

37、ty measurements), the lower designation must be usedto ensure conformance with 6.5 below.6.4 For the sake of uniformity of nomenclature in identifying the viscosity characteristics of hydraulic fluids, the followingdesignation shall be used:ISO VG xxLyy-zz (VI)where xx is the new oil viscosity grade

38、 as determined by Classification D2422 (Table 2); Lyy is the low temperature viscositygrade as determined in 6.1; zz is the high temperature sheared viscosity designation as determined in 6.2; and VI is the viscosityindex designation as determined in 6.3.6.4.1 If the new oil viscosity does not meet

39、a grade described by Classification D2422, the ISO VG xx portion of the designationdoes not apply. In such cases, the Lyy-zz (VI) designation may still be used, and the use of any other descriptors for the new oilis at the discretion of the fluid marketer.6.4.2 Examples of use of this practice are s

40、hown in Table 3.TABLE 1 Low Temperature Viscosity Grades for Hydraulic FluidClassificationsViscosity GradeTemperature, C, for Brookfield Viscosityof 750 mPasAmin maxL5 . 50L7 49 42L10 41 33L15 32 23L22 22 15L32 14 8L46 7 2L68 1 4L100 5 10L150 11 16A The temperature range for a given L-grade is appro

41、ximately equivalent to that foran ISO grade of the same numerical designation and having a viscosity index of100, that is, the temperature range for the L10 grade is approximately the same asthat for an ISO VG 10 grade with a viscosity index of 100.D6080 12a36.5 An oil blender may use any manufactur

42、ing control that seems appropriate to his operation. However, it is the responsibilityof the blender to ensure that all production fully meets the requirements for the viscosity designation on the container.7. Interpretation of Results7.1 The designation determined for a hydraulic fluid as described

43、 in 6.4 may be used in combination with a manufacturersviscosity recommendations for specific equipment to estimate an acceptable temperature range over which that fluid may be usedin that equipment.7.2 The low temperature grade determined in 6.1, Lyy, defines the lowest recommended fluid temperatur

44、e at which the fluid maybe used in equipment with a start-up, under load limit of 750 mPas, max.7.2.1 The low temperature limit is determined by comparing the Lyy designation with the corresponding temperature in Table1.7.2.2 Example 1aFor an oil with the designation:ISO VG 46L32-40 ,the low tempera

45、ture grade is defined by L32. Reference to Table 1 indicates that this oil has a viscosity of 750 mPas at atemperature between 8 and 14C. Hence, in equipment which has a low temperature start-up viscosity limit of 750 mPas, theoil in this example may be used down to at least 8C.7.2.3 Example 2aFor a

46、n oil with the designation:ISO VG 68L46-57the low temperature grade is defined by L46. Reference to Table 1 indicates that this oil has a viscosity of 750 mPas at atemperature between 2 and 7C. Hence, in equipment which has a low temperature start-up viscosity limit of 750 mPas, the oilin this examp

47、le may be used down to at least 2C.7.2.4 This practice is not quantitative when a manufacturer specifies lower or higher start-up viscosity limits. However, theprocess described in 6.1 can be used to determine low temperature limitations corresponding to any start-up viscosity.7.3 The high temperatu

48、re designation determined in 6.2 and the viscosity index determined in 6.3, zz (VI), can be used incombination with the data in Figs. 1-4 to estimate high temperature operating limits (Fig. 1 and Fig. 2) and optimum operatingtemperatures (Fig. 3 and Fig. 4) for the fluid.7.3.1 Fig. 1 and Fig. 2 appl

49、y directly to equipment which has minimum operating kinematic viscosity limits of 10 and 13 mm2/s,respectively.7.3.1.1 Find the value zz on the horizontal axis labeled High Temperature Viscosity Designation.7.3.1.2 Read vertically from the point defined by 7.3.1.1 to the curve corresponding to the viscosity index, VI, interpolating,if necessary.7.3.1.3 Read horizontally from the point defined by 7.3.1.2 to the vertical axis labeled Temperature, C, for a KinematicViscosity of 10 (or 13) mm2/s. This is the upper te