ASTM D6080-2018 red 5625 Standard Practice for Defining the Viscosity Characteristics of Hydraulic Fluids.pdf

1、Designation: D6080 12aD6080 18Standard 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 mm1 mm2/s is equivalent to 1 centistoke(cSt).1.3 This practice is applicable to fluids ranging in kinematic viscosity from about 4 mm2/s to 150 mm2/s as measured at areference temperature of 40 C and

5、to temperatures from 50 C to +16 C 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 nee

6、d to expand the 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.1.5 This international standard was developed in accordance with internationally recognized principles on standard

7、izationestablished 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:2D445 Test Method for Kinematic Viscosity of Transpa

8、rent and Opaque Liquids (and Calculation of Dynamic Viscosity)D2270 Practice for Calculating Viscosity Index from Kinematic Viscosity at 40 C and 100 CD2422 Classification of Industrial Fluid Lubricants by Viscosity SystemD2983 Test Method for Low-Temperature Viscosity of Automatic Transmission Flui

9、ds, Hydraulic Fluids, and Lubricants usinga Rotational ViscometerD5621 Test Method for Sonic Shear Stability of Hydraulic FluidsE29 Practice for Using Significant Digits in Test Data to Determine Conformance with SpecificationsE1953 Practice for Description of Thermal Analysis and Rheology Apparatus

10、2.2 Society of Automotive Engineers (SAE) Standards:3J300 Engine Oil Viscosity ClassificationJ306 Axle and Manual Transmission Lubricant Viscosity Classification3. Terminology3.1 Definitions:3.1.1 hydraulic fluid, na liquid used in hydraulic systems for lubrication and transmission of power.3.1.2 ki

11、nematic viscosity, nthe ratio of the dynamic viscosity to the density of a liquid.3.1.2.1 Discussion1 This practice is under the jurisdiction of ASTM Committee D02 on Petroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility of SubcommitteeD02.N0 on Hydraulic Fluids.Current e

12、dition approved Nov. 1, 2012June 1, 2018. Published February 2013July 2018. Originally approved in 1997. Last previous edition approved in 2012 asD6080D6080 12a.12. DOI: 10.1520/D6080-12A.10.1520/D6080-18.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Se

13、rvice at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.3 Available from Society of Automotive Engineers SAE International (SAE), 400 Commonwealth Dr., Warrendale, PA 15096-0001,15096, http:/www.sae.org.This docu

14、ment 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 be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as

15、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 of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United

16、 States1For gravity flow under a given hydrostatic head, the pressure head of a liquid is proportional to its density. Therefore, kinematicviscosity is a measure of the resistance to flow of a liquid under gravity.3.1.3 Newtonian oil or fluid, nan oil or fluid that at a given temperature exhibits a

17、constant viscosity at all shear rates or shearstresses.3.1.4 non-Newtonian oil or fluid, nan 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 impro

18、ver) as a result 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

19、the applied shear stress and 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 kinema

20、tic 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

21、, 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 tempe

22、rature viscositiesbefore and after exposure to high shear stress.4.2.1 Since the performance of fluids at temperatures higher than 40 C 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

23、practice 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 unde

24、rthe 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

25、 establish 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 selecti

26、ng 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 n

27、o 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 o

28、perating 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 viscosit

29、y grade of a fluid is based on the viscosity of new oil measured using a Brookfield viscometer,rotational viscometer (see Practice E1953), Test Method D2983.D6080 1826.1.1 The viscosity shall be interpolated from measurements at three temperatures spanning the temperature at which theviscosity is 75

30、0 mPas. 750 mPas. A smooth graph of these data (log viscosity versus temperature) determines the temperature atwhich the oil 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 gr

31、ade is determined by matching the temperature determined in 6.1.2 with the requirementsshown in Table 1.6.2 The high temperature viscosity designation of a fluid is the 40 C kinematic viscosity (Test Method D445) of a fluid whichhas been sheared using Test Method D5621.6.2.1 The kinematic viscosity

32、determined in 6.2 shall be rounded to a whole number in 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 40 C kinematic viscosity (Test Method D445) of the new fluid, rounded per 6.2.1.6

33、.2.3 If the 40 C kinematic viscosity from 6.2.1 fails to meet 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 conf

34、ormance with 6.5 below.6.3 The viscosity index designation 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 P

35、ractice E29. This valueis the viscosity index designation.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 t

36、en units inaccordance with Practice E29.NOTE 2The guidelines 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 ar

37、e used for other purposes.6.3.3 If the viscosity index fails 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 specificatio

38、ns, or variability in kinematic viscosity or shear stability 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:I

39、SO VG xxLyy-zz (VI)where xx is the new oil viscosity grade 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 deter

40、mined in 6.3.6.4.1 If the new oil viscosity does not meet 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 f

41、luid marketer.6.4.2 Examples of use of this practice are shown in Table 3.TABLE 1 Low Temperature Viscosity Grades for Hydraulic FluidClassificationsViscosity GradeTemperature, C, for BrookfieldRotational Viscosityof 750 mPasAmin maxL5 . 50L7 49 42L10 41 33L15 32 23L22 22 15L32 14 8L46 7 2L68 1 4L10

42、0 5 10L150 11 16A The temperature range for a given L-grade is approximately 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 viscos

43、ity index of 100.D6080 1836.5 An oil blender may use any manufacturing 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 Resul

44、ts7.1 The designation determined for a hydraulic fluid as described 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 dete

45、rmined in 6.1, Lyy, defines the lowest recommended fluid temperature 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

46、 1aFor an oil with the designation:ISO VG 46L32-40 ,the low temperature grade is defined by L32. Reference to Table 1 indicates that this oil has a viscosity of 750 mPas at atemperature between 8 C and 14 C. Hence, in equipment which has a low temperature start-up viscosity limit of 750 mPas,the oil

47、 in this example may be used down to at least 8 C.7.2.3 Example 2aFor an 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 C and 7 C. Hence, in equipment which has a

48、low temperature start-up viscosity limit of 750 mPas, theoil in this example may be used down to at least 2 C.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

49、 limitations corresponding to any start-up viscosity.7.3 The high temperature 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 apply directly to equipment which has minimum operating kinematic viscosity limits of 10 mm2/s and13 mm2/s, respectively.7.3.1.1 Find the value