1、Designation: D128 98 (Reapproved 2014)1Standard Test Methods forAnalysis of Lubricating Grease1This standard is issued under the fixed designation D128; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A n
2、umber in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S. Department of Defense.1NOTEA section reference in subsection 21.1 was corrected edit
3、orially in July 2015.1. Scope1.1 These test methods for analysis cover greases of theconventional type, which consist essentially of petroleum oiland soap. The constituents that can be determined are soap,unsaponifiable matter (petroleum oil, and so forth), water, freealkalinity, free fatty acid, fa
4、t, glycerin, and insolubles.NOTE 1Any of the test methods described herein are best used by anexperienced grease analyst who may also be able to make appropriateadaptations of the techniques as occasion requires.1.2 A supplementary test method is provided in AppendixX1. This test method is intended
5、primarily for application togreases containing thickeners that are essentially insoluble inn-hexane, and to greases that cannot be analyzed by conven-tional methods because of the presence of such constituents asnonpetroleum fluids or nonsoap-type thickeners, or both. Insome cases, these constituent
6、s can react with strong acid oralkaline solutions.1.3 These test methods appear in the following order:SectionsAsh Determination 711Insolubles, Soap, Fat, Petroleum Oil,and Unsaponifiable Matter1220Free Alkali and Free Acid 2123Water 24Glycerin (Quantitative) 25291.4 The values stated in SI units ar
7、e to be regarded asstandard. No other units of measurement are included in thisstandard.1.5 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
8、, and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D95 Test Method for Water in Petroleum Products andBituminous Materials by DistillationD156 Test Method for Saybolt Color of Petroleum Products(Saybolt Chromometer Method)D217 Test Me
9、thods for Cone Penetration of LubricatingGreaseD445 Test Method for Kinematic Viscosity of Transparentand Opaque Liquids (and Calculation of Dynamic Viscos-ity)D473 Test Method for Sediment in Crude Oils and Fuel Oilsby the Extraction MethodD804 Terminology Relating to Pine Chemicals, IncludingTall
10、Oil and Related ProductsD1078 Test Method for Distillation Range of Volatile Or-ganic LiquidsD1193 Specification for Reagent WaterD1353 Test Method for Nonvolatile Matter in Volatile Sol-vents for Use in Paint, Varnish, Lacquer, and RelatedProducts3. Terminology3.1 Definitions:3.1.1 asphalt, na dark
11、 brown-to-black cementitious mate-rial in which the predominating constituents are bitumens.3.1.1.1 DiscussionAsphalt can be a natural product or amaterial obtained from petroleum processing.3.1.2 candle pitch, na dark brown-to-black, tarry or solid,by-product residue from soap and candle stock manu
12、facture,refining of vegetable oils, refining of wool grease, or refining ofrefuse animal fats.3.1.3 cup grease, nany lubricating grease having physicalproperties, such as consistency and texture, suitable for its usein spring-loaded or screw-type lubricating cups.1These test methods are under the ju
13、risdiction of ASTM Committee D02 onPetroleum Products, Liquid Fuels, and Lubricants and are the direct responsibilityof Subcommittee D02.G0.01 on Chemical and General Laboratory Tests.Current edition approved Oct. 1, 2014. Published November 2014. Originallyapproved in 1922. Last previous edition ap
14、proved in 2008 as D128 98(2008).DOI: 10.1520/D0128-98R14E01.2For 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 website.C
15、opyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States13.1.3.1 DiscussionCup greases are predominantly NLGINo. 3 or 4 calcium greases, but grease types other than calciumare also used.3.1.4 degras (wool fat, wool grease, wool wax), na fat-lik
16、ematerial comprised primarily of sterols, other higher alcohols,and fatty acids, obtained from the solvent extraction of sheepswool.3.1.5 free alkali, n in lubricating grease, unreacted basic(alkaline) material present in the product.3.1.5.1 DiscussionMany greases are made with a slightexcess of alk
17、ali to ensure complete saponification. Free alkaliis determined by acidification of a solvent-thinned specimenand back titration with standardized, alcoholic potassiumhydroxide. It is expressed in terms of the predominating alkaliand a mass % of the total grease composition (for example,mass % lithi
18、um hydroxide).3.1.6 free fatty acid, nin lubricating grease, unreactedcarboxylic acid(s) present in the product.3.1.6.1 DiscussionSome greases are made with a slightexcess of carboxylic acid to ensure a non-alkaline product.Free fatty acid is determined by neutralization of a solvent-thinned specime
19、n with standardized, alcoholic potassium hy-droxide. Regardless of the actual composition of the carboxylicacid(s), it is expressed as free oleic acid and as a mass % of thetotal grease composition.3.1.7 insolubles, nin lubricating greases analysis, thematerial remaining after the acid hydrolysis, w
20、ater extraction,and solvent extraction of soap-thickened greases.3.1.7.1 DiscussionConsisting of such products asgraphite, molybdenum disulfide, insoluble polymers, and soforth.3.1.8 lubricating grease, na semi-fluid to solid product ofa dispersion of a thickener in a liquid lubricant.3.1.8.1 Discus
21、sionThe qualifying term, lubricating,should always be used. The term, grease, used without thequalifier refers to a different product, namely certain natural orprocessed animal fats, such as tallow, lard, and so forth.3.1.9 mixed base, adjin lubricating grease, the descriptionof a thickener system c
22、omposed of soaps of two metals.3.1.9.1 DiscussionAlthough mixed-base grease can bemade with soaps of more than two metals, in practice, such israrely, if ever, encountered. All of the soaps need not bethickeners, although the major soap constituent will be onecapable of forming a lubricating grease
23、structure. Because themixed soaps are seldom present in equal amounts. The pre-dominant soap is referred to first.NLGI Lubricating Grease Guide33.1.10 montan wax, na wax-like material comprised pri-marily of montanic acid and its ester, higher aliphatic alcohols,and resins obtained from the solvent
24、extraction of lignite.3.1.11 neutralization number, nof petroleum oil, the quan-tity of acid or base required to titrate to neutrality andexpressed as equivalent milligrams of potassium hydroxide pergram of sample. D8043.1.12 NLGI, nNational Lubricating Grease Institute.3.1.13 NLGI number, na numeri
25、cal scale for classifyingthe consistency range of lubricating greases and based on theTest Methods D217 worked penetration.NLGI Lubricating Grease Guide3.1.14 non-soap thickener (synthetic thickener, inorganicthickener, organic thickener), nin lubricating grease, any ofseveral specially treated or s
26、ynthetic materials, exceptingmetallic soaps, that can be thermally or mechanically dispersedin liquid lubricants to form the lubricating grease structure.NLGI Lubricating Grease Guide3.1.15 residuum, na liquid or semi-liquid product ob-tained as residue from the distillation of petroleum andconsisti
27、ng primarily of asphaltic hydrocarbons.3.1.15.1 DiscussionAlso known as asphaltic oil, asphal-tum oil, liquid asphalt, black oil, petroleum tailings, andresidual oil.3.1.16 rosin oil, na viscous, oily liquid obtained as acondensate when the residue (rosin) from turpentine produc-tion is subjected to
28、 dry, destructive distillation.3.1.16.1 DiscussionAlso used to describe specially com-pounded oils having a rosin base.3.1.17 saponification, nthe interaction of fats, fatty acids,or esters generally with an alkali to form the metallic salt,which is commonly called soap.3.1.17.1 DiscussionSoap thick
29、eners are most often madeby in situ saponification in the lubricating grease base oil.However, the use of pre-formed soaps is also common;dispersion is effected by mechanical means and usually withheat. NLGI Lubricating Grease Guide3.1.18 single base, adj in lubricating grease, relating to athickene
30、r comprised of soaps of only one metal.3.1.19 soap, nin lubricating grease, a product formed inthe saponification (neutralization) of fats, fatty acids, or estersby inorganic bases.3.1.20 Soxhlet apparatus, na device, usually of glass,used to extract soluble material from a mixture of soluble andins
31、oluble (generally solid) materials, by passing a volatilesolvent through the sample and recirculating the solvent byrefluxing.3.1.21 tar, na brown or black, bituminous, liquid orsemi-solid comprised primarily of bitumens condensed in theprocessing of coal, petroleum, oil-shale, wood, or other organi
32、cmaterials.3.1.22 thickener, nin lubricating grease, a substance com-posed of finely divided solid particles dispersed in a liquidlubricant to form the products structure.3.1.22.1 DiscussionThe thickener can be fibers (such asvarious metallic soaps) or plates or spheres (such as certainnon-soap thic
33、keners), which are insoluble or, at most, only veryslightly soluble in the liquid lubricant. The general require-ments are that the solid particles be extremely small, uniformly3Available from National Lubricating Grease Institute, 4635 Wyandotte St.,Kansas City, MO 64112-1596.D128 98 (2014)12disper
34、sed, and capable of forming a relatively stable, gel-likestructure with the liquid lubricant. D2173.1.23 thimble, nin Soxhlet apparatus, a closed-end po-rous cylinder used to hold the material to be extracted, usuallymade of thick matted filter paper but sometimes made ofceramic.3.1.24 total fluid c
35、onstituent, nin lubricating greaseanalysis, the n-hexane-soluble material extracted from thelubricating grease sample.3.1.24.1 DiscussionTypical materials include petroleumoil, non-petroleum fluid, soluble fats, and soluble additives.3.1.25 total n-hexane-insoluble material, nin lubricatinggrease an
36、alysis, that portion of grease (excluding free alkali)that is essentially insoluble in n-hexane.3.1.25.1 DiscussionTypical materials include thickeners,fillers, inorganic salts, asphaltenes, or any combinations ofthese (also includes insoluble materials found in the analysis ofcontaminated grease).
37、Free alkali content is generally insignifi-cant.3.1.26 unsaponifiable matter, nin lubricating grease, or-ganic materials, either added or found with fatty materials,which do not react during saponification.4. Significance and Use4.1 These test methods can be used to identify and estimatethe amount o
38、f some of the constituents of lubricating greases.These test methods are applicable to many, but not all, greases.4.2 Composition should not be considered as having anydirect bearing on service performance unless such correlationis established.NOTE 2Details on other test methods for grease analysis
39、can be foundin other reference material.4,5,65. Reagents5.1 Purity of ReagentsReagent grade chemicals shall beused in all tests. Unless otherwise indicated, it is intended thatall reagents shall conform to the specifications of the Commit-tee on Analytical Reagents of the American Chemical Society,w
40、here such specifications are available.7Other grades may beused, provided it is first ascertained that the reagent is ofsufficiently high purity to permit its use without lessening theaccuracy of the determination.5.2 Purity of WaterUnless otherwise indicated, referencesto water shall be understood
41、to mean reagent water conformingto Specification D1193, Type III.5.3 AcetoneAmerican Chemical Society Reagent GradeAcetone. (WarningExtremely flammable. Vapors may causeflash fires.)5.4 Alcohol (50 %)The alcohol shall be prepared fromcommercial 95 % ethanol or denatured alcohol8,9(WarningFlammable.
42、Denatured. Cannot be made nontoxic) by distillingfrom NaOH and neutralizing exactly with NaOH or KOH usingphenolphthalein as the indicator. (Warning In addition toother precautions, avoid skin contact or ingestion.) Dilute withan equal volume of water.5.5 Ammonium Carbonate(NH4)2CO3.(WarningHarmful
43、if swallowed.) (WarningHarmful if swallowed.)5.6 Butter Yellow Indicator (0.02 g mL)Toluene solution(WarningFlammable. Vapor harmful) ofp-dimethylaminoazobenzene. (WarningSuspected carcino-gen. In addition to other precautions, avoid inhalation or skincontact.)5.7 t-Butyl Alcohol, melting point 24 C
44、 to 25.5 C(WarningFlammable liquid; causes eye burns).5.8 Carbon Disulfide (CS2). (WarningExtremely flam-mable. Poison. Vapor may cause flash fire. Vapor harmful.Capable of self-ignition at 100 C or above. Harmful or fatal ifswallowed. May be absorbed through the skin.)5.9 Ethyl Ether. (WarningExtre
45、mely flammable. Harmfulif inhaled. May cause eye injury. Effects may be delayed. Mayform explosive peroxides. Vapors may cause flash fire. Mod-erately toxic. Irritating to skin.)5.10 n-hexane, high-purity grade,9,10conforming to therequirements of Table 1.(WarningExtremely flammable.Harmful if inhal
46、ed. May produce nerve cell damage. Vaporsmay cause flash fire.)4Stanton, G. M., “Examination of Grease by Infrared Spectroscopy,” NLGISpokesman, Vol 38, No. 5, August 1974, pp. 153165.5Stanton, G. M., “Grease Analysis, a Modern Multitechnique Approach,”Preprint NLGI Annual Meeting, Oct 2629, 1975.6B
47、onomo, F. S., and Schmidt, J. J. E., “Development of Schematic AnalyticalProcedures for Synthetic Lubricants and Their Additives,” WADC Technical Report54-464, Part IV, July 1957 (U.S. Government No. AD-130922).7Reagent Chemicals, American Chemical Society Specifications, AmericanChemical Society, W
48、ashington, DC. For Suggestions on the testing of reagents notlisted by the American Chemical Society, see Annual Standards for LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeiaand National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.8The s
49、ole source of supply of denatured grain alcohol known to the committeeat this time is Formulas 1, 23-A, 30, and 35-A, as described in Publication No. 368,“Formulas for Denatured Alcohol,” U.S. Treasury Dept., Internal Revenue Service.9If you are aware of alternative suppliers, please provide this information toASTM International Headquarters. Your comments will receive careful consider-ation at a meeting of the responsible technical committee,1which you may attend.10The sole source of supply of n-hexane, high-
