1、Designation: D 128 98 (Reapproved 2008)An American National StandardStandard Test Methods forAnalysis of Lubricating Grease1This standard is issued under the fixed designation D 128; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision,
2、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.This standard has been approved for use by agencies of the Department of Defense.1. Scope1.1 These test methods for an
3、alysis 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, fat, glycerin, and insolubles.NOTE 1Any of the test methods
4、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 primarily for application togreases containing thickeners
5、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 constituents can react with strong acid oralkaline solutions.1.3 Thes
6、e test methods appear in the following order:SectionsAsh Determination 7-11Insolubles, Soap, Fat, Petroleum Oil,and Unsaponifiable Matter12-20Free Alkali and Free Acid 21-23Water 24Glycerin (Quantitative) 25-291.4 The values stated in SI units are to be regarded asstandard. No other units of measure
7、ment 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, and determine the applica-bility of regulatory limit
8、ations prior to use.2. Referenced Documents2.1 ASTM Standards:2D95 Test Method for Water in Petroleum Products andBituminous Materials by DistillationD 156 Test Method for Saybolt Color of Petroleum Prod-ucts (Saybolt Chromometer Method)D 217 Test Methods for Cone Penetration of LubricatingGreaseD 4
9、45 Test Method for Kinematic Viscosity of Transparentand Opaque Liquids (and Calculation of Dynamic Viscos-ity)D 473 Test Method for Sediment in Crude Oils and FuelOils by the Extraction MethodD 804 Terminology Relating to Naval Stores, Including TallOil and Related ProductsD 1078 Test Method for Di
10、stillation Range of VolatileOrganic LiquidsD 1193 Specification for Reagent WaterD 1353 Test Method for Nonvolatile Matter in VolatileSolvents for Use in Paint, Varnish, Lacquer, and RelatedProducts3. Terminology3.1 Definitions:3.1.1 asphalt, na dark brown-to-black cementitious ma-terial in which th
11、e 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 manufacture,refining of vegetable oils, refining of wo
12、ol 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 jurisdiction of ASTM Committee D02 onPetroleum Produ
13、cts and Lubricants and are the direct responsibility of Subcommit-tee D02.G0.01 on Chemical and General Laboratory Tests.Current edition approved May 1, 2008. Published July 2008. Originally approvedin 1922. Last previous edition approved in 2003 as D 12898(2003)1.2For referenced ASTM standards, vis
14、it 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.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2
15、959, United States.3.1.3.1 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), nafat-like material comprised primarily of sterols, other higheralcohols, and fatty acids, obtained from
16、 the solvent extractionof sheeps wool.3.1.5 free alkali, nin 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 solvent-t
17、hinned 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) presen
18、t 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 composition of th
19、e 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 DiscussionConsisting o
20、f such products as graph-ite, molybdenum disulfide, insoluble polymers, and so forth.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 without t
21、hequalifier 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 with
22、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 soap
23、 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,thequantity of acid or
24、 base required to titrate to neutrality andexpressed as equivalent milligrams of potassium hydroxide pergram of sample. D 8043.1.12 NLGI, nNational Lubricating Grease Institute.3.1.13 NLGI number, na numerical scale for classifyingthe consistency range of lubricating greases and based on theTest Met
25、hods D 217 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 dispersedi
26、n 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, asphal
27、-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-pounded
28、 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.However
29、, 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 formed
30、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 recir
31、culating 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 substancecomposed of finely divided so
32、lid 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 lubricant. Th
33、e general require-ments are that the solid particles be extremely small, uniformlydispersed, and capable of forming a relatively stable, gel-likestructure with the liquid lubricant. D 2173.1.23 thimble, nin Soxhlet apparatus, a closed-end po-rous cylinder used to hold the material to be extracted, u
34、suallymade of thick matted filter paper but sometimes made ofceramic.3Available from National Lubricating Grease Institute, 4635 Wyandotte St.,Kansas City, MO 64112-1596.D 128 98 (2008)23.1.24 total fluid constituent, nin lubricating greaseanalysis, the n-hexane-soluble material extracted from thelu
35、bricating 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-hexan
36、e.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 lubricating
37、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 many, b
38、ut 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 grade ch
39、emicals 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 ascertai
40、ned 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 D 1193, Type III.5.3 AcetoneAmerican Chemical
41、 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 NaOH
42、 or KOH usingphenolphthalein as the indicator. (WarningIn 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)Toluene so
43、lution(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). (WarningExtrem
44、ely 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. Harm-ful if inhaled. May cause eye injury. Effects may be delayed.May form explosi
45、ve peroxides. Vapors may cause flash fire.Moderately 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.)5.11 Hydrochloric Acid (37 %)Concen
46、trated acid (HCl).(WarningPoison. Corrosive. May be fatal if swallowed.Liquid and vapor cause severe burns. Harmful if inhaled.)5.12 Hydrochloric Acid, Standard Solution (0.5 N)Prepare and standardize a 0.5 N solution of HCl.5.13 Hydrochloric Acid (10 %), a solution containing 10 %by weight of conce
47、ntrated HCl in water, with a permissiblevariation of 0.5 %.5.14 Hydrochloric Acid (1 + 3)Mix one volume of con-centrated HCl (37 %) with three volumes of water.5.15 Methyl Red Indicator Solution.(WarningFlammable. Avoid skin contact or ingestion.)4Stanton, G. M., “Examination of Grease by Infrared S
48、pectroscopy,” 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 Synthetic Lubricants and The
49、ir 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 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 sole source of supply of denatured gr
