1、Designation: D128 98 (Reapproved 2014)Standard 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 nu
2、mber 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.1. Scope1.1 These test methods for analysis cover greases of th
3、econventional 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, fat, glycerin, and insolubles.NOTE 1Any of the test methods described herein are best
4、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 primarily for application togreases containing thickeners that are essentially insol
5、uble 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 constituents can react with strong acid oralkaline solutions.1.3 These test methods appear in t
6、he 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 are to be regarded asstandard. No other units of measurement are included in thisstand
7、ard.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, and determine the applica-bility of regulatory limitations prior to use.2. Referen
8、ced 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 Methods for Cone Penetration of LubricatingGreaseD445 Test Method for Kinematic Viscos
9、ity 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 Oil and Related ProductsD1078 Test Method for Distillation Range of Volatile Or-gani
10、c 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 brown-to-black cementitious mate-rial in which the predominating constituents are b
11、itumens.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 manufacture,refining of vegetable oils, refining of wool grease, or refining ofrefuse an
12、imal 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 jurisdiction of ASTM Committee D02 onPetroleum Products, Liquid Fuels, and Lubricants
13、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 approved in 2008 as D128 98(2008).DOI: 10.1520/D0128-98R14.2For referenced ASTM standa
14、rds, 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.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA
15、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-likematerial comprised primarily of sterols, other higher alcohols,and fatty acids, obtain
16、ed 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 alkali to ensure complete saponification. Free alkaliis determined by acidification of a s
17、olvent-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 % lithium hydroxide).3.1.6 free fatty acid, nin lubricating grease, unreactedcarboxylic acid(s
18、) 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 specimen with standardized, alcoholic potassium hy-droxide. Regardless of the actual compositi
19、on 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, water extraction,and solvent extraction of soap-thickened greases.3.1.7.1 DiscussionCons
20、isting 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 DiscussionThe qualifying term, lubricating,should always be used. The term, grease, used with
21、out 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 composed of soaps of two metals.3.1.9.1 DiscussionAlthough mixed-base grease can bemade
22、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 structure. Because themixed soaps are seldom present in equal amounts. The pre-dominant
23、 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 extraction of lignite.3.1.11 neutralization number, nof petroleum oil, the quan-tity of
24、 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 numerical scale for classifyingthe consistency range of lubricating greases and based on theT
25、est 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 synthetic materials, exceptingmetallic soaps, that can be thermally or mechanically disp
26、ersedin 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 andconsisting primarily of asphaltic hydrocarbons.3.1.15.1 DiscussionAlso known as asphaltic oil,
27、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 dry, destructive distillation.3.1.16.1 DiscussionAlso used to describe specially com-p
28、ounded 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 thickeners are most often madeby in situ saponification in the lubricating grease base oil.H
29、owever, 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 athickener comprised of soaps of only one metal.3.1.19 soap, nin lubricating grease, a product f
30、ormed 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 andinsoluble (generally solid) materials, by passing a volatilesolvent through the sample and
31、 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 organicmaterials.3.1.22 thickener, nin lubricating grease, a substance com-posed of finely di
32、vided 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 thickeners), which are insoluble or, at most, only veryslightly soluble in the liquid lubri
33、cant. 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)2dispersed, and capable of forming a relatively stable, gel-likestructure with the liquid lubri
34、cant. 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 constituent, nin lubricating greaseanalysis, the n-hexane-soluble material extracted from
35、 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 analysis, that portion of grease (excluding free alkali)that is essentially insoluble in n
36、-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). Free alkali content is generally insignifi-cant.3.1.26 unsaponifiable matter, nin lubric
37、ating 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 of some of the constituents of lubricating greases.These test methods are applicable to m
38、any, 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 can be foundin other reference material.4,5,65. Reagents5.1 Purity of ReagentsReagent gr
39、ade 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,where such specifications are available.7Other grades may beused, provided it is first as
40、certained 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 to mean reagent water conformingto Specification D1193, Type III.5.3 AcetoneAmerican Che
41、mical 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. Denatured. Cannot be made nontoxic) by distillingfrom NaOH and neutralizing exactly with
42、 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 if swallowed.) (WarningHarmful if swallowed.)5.6 Butter Yellow Indicator (0.02 g/mL)Tolu
43、ene 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 to 25.5C (WarningFlammable liquid; causes eye burns).5.8 Carbon Disulfide (CS2). (Warning
44、Extremely flam-mable. Poison. Vapor may cause flash fire. Vapor harmful.Capable of self-ignition at 100C or above. Harmful or fatal ifswallowed. May be absorbed through the skin.)5.9 Ethyl Ether. (WarningExtremely flammable. Harmfulif inhaled. May cause eye injury. Effects may be delayed. Mayform ex
45、plosive 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 inhaled. May produce nerve cell damage. Vaporsmay cause flash fire.)4Stanton, G. M., “Examinatio
46、n 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, 1975.6Bonomo, F. S., and Schmidt, J. J. E., “Development of Schematic AnalyticalProcedures for Syn
47、thetic 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, Washington, DC. For Suggestions on the testing of reagents notlisted by the American Chemica
48、l 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 sole source of supply of denatured grain alcohol known to the committeeat this time is Formu
49、las 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-purity grade, known to thecommittee at this time is Phillips Petroleum Co., Special Products Div.
