1、Designation: D 893 05aAn American National StandardStandard Test Method forInsolubles in Used Lubricating Oils1This standard is issued under the fixed designation D 893; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of l
2、ast revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) 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. Scope*1.1 This test method covers the determin
3、ation of pentaneand toluene insolubles in used lubricating oils.1.2 Procedure A covers the determination of insolubleswithout the use of coagulant in the pentane. It provides anindication of the materials that can readily be separated fromthe oil-solvent mixtures by centrifuging.1.3 Procedure B cove
4、rs the determination of insolubles inoils containing detergents and employs a coagulant for both thepentane and toluene insolubles. In addition to the materialsseparated by using Procedure A, this coagulation procedureseparates some finely divided materials that may be suspendedin the oil.NOTE 1Resu
5、lts obtained by Procedures A and B should not becompared since they usually give different values. The same procedureshould be employed when comparing values obtained periodically on anoil in use or when comparing results determined by two or morelaboratories.1.4 The values stated in SI units are to
6、 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 and
7、 determine the applica-bility of regulatory limitations prior to use. For specificwarning statements, see Section 7 and 9.1.1.2. Referenced Documents2.1 ASTM Standards:2D 1193 Specification for Reagent WaterD 4057 Practice for Manual Sampling of Petroleum andPetroleum ProductsD 4177 Practice for Aut
8、omatic Sampling of Petroleum andPetroleum Products3. Terminology3.1 Definitions:3.1.1 coagulate, vto cause to become viscous or thick-ened into a coherent mass.3.1.2 coagulated pentane insolubles, nin used oil analy-sis, separated matter that results when a coagulant is added toa solution of used oi
9、l in pentane.3.1.2.1 DiscussionThe addition of a coagulant will aid inseparating finely divided materials that may have been held insuspension because of the dispersant characteristics of the oil.3.1.3 coagulated toluene insolubles, nin used oil analysis,coagulated and separated matter not soluble i
10、n pentane ortoluene.3.1.4 pentane insolubles, nin used oil analysis, separatedmatter resulting when a used oil is mixed with pentane.3.1.4.1 DiscussionIn this test method, the separation iseffected by centrifugation.3.1.5 toluene insolubles, nin used oil analysis, the portionof pentane insolubles no
11、t soluble in toluene.3.1.6 used oil, nany oil that has been in a piece ofequipment (for example, an engine, gearbox, transformer, orturbine), whether operated or not.3.1.6.1 DiscussionIn this test method, the oil can be anyoil that has been used for lubrication.3.2 Definitions of Terms Specific to T
12、his Standard:3.2.1 insoluble resins, nin used oil analysis, separatedmatter soluble in toluene but not pentane.3.2.1.1 DiscussionInsoluble resins can be calculated foreither Procedure A or B by subtracting the toluene insolublesfrom the pentane insolubles.4. Summary of Test Method4.1 Procedure AA re
13、presentative sample of used lubricat-ing oil is mixed with pentane and centrifuged. The oil solutionis decanted and the precipitate washed twice with pentane,dried, and weighed to give the pentane insolubles. For toluene1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Pr
14、oducts and Lubricants and is the direct responsibility of SubcommitteeD02.06 on Analysis of Lubricants.Current edition approved Nov. 1, 2005. Published November 2005. Originallyapproved in 1967. Last previous edition approved in 2005 as D 89305.2For referenced ASTM standards, visit the ASTM website,
15、 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.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Dri
16、ve, PO Box C700, West Conshohocken, PA 19428-2959, United States.insolubles, a separate sample of the oil is mixed with pentaneand then centrifuged. The precipitate is washed twice withpentane, once with toluene-alcohol solution, and once withtoluene. The insoluble material is then dried and weighed
17、 togive the insolubles.4.2 Procedure BA representative sample of used lubricat-ing oil is mixed with pentane-coagulant solution and centri-fuged. The precipitate is washed twice with pentane, dried, andweighed to give coagulated pentane insolubles. For coagulatedtoluene insolubles a separate sample
18、of the oil is mixed withpentane-coagulant solution and centrifuged. The precipitate iswashed twice with pentane, once with toluene-alcohol solution,and once with toluene. The insoluble material is then dried andweighed to give coagulated toluene insolubles.5. Significance and Use5.1 Pentane insolubl
19、es can include oil-insoluble materialsand some oil-insoluble resinous matter originating from oil oradditive degradation, or both.5.2 Toluene insoluble materials can come from (1) externalcontamination, (2) fuel carbon and highly carbonized materialsfrom degradation of fuel, oil, and additives, or (
20、3) engine wearand corrosion materials.5.3 A significant change in pentane insolubles, tolueneinsolubles (with or without coagulant), and insoluble resinsindicates a change in oil which could lead to lubrication systemproblems.5.4 Insolubles measured can also assist in evaluating theperformance chara
21、cteristics of a used oil or in determining thecause of equipment failure.6. Apparatus6.1 Centrifuge Tube, cone-shaped, conforming to the di-mensions given in Fig. 1, and made of thoroughly annealedglass. The graduations, numbered as shown in Fig. 1, shall beclear and distinct and the mouth constrict
22、ed in shape forclosure with a cork. Scale error tolerances and smallestgraduations between various calibration marks are given inTable 1 and apply to calibrations made with air-free water at20C.6.2 Centrifuge, meeting all safety requirements for normaluse and capable of whirling two or more filled c
23、entrifuge tubesat a speed that can be controlled to give a relative centrifugalforce (rcf) between 600 and 700 at the tips of the tubes. Therevolving head, trunnion rings, and trunnion cups, includingthe rubber cushion, shall be soundly constructed to withstandthe maximum centrifugal force capable o
24、f being delivered bythe power source. The trunnion cups and cushions shall firmlysupport the tubes when the centrifuge is in motion. Thecentrifuge shall be enclosed by a metal shield or case strongenough to eliminate danger if any breakage occurs. Calculatethe speed of the rotating head as follows:S
25、peed, rpm 5 1337 =rcf/d (1)where:rcf = relative centrifugal force, andd = diameter swing, mm, measured between tips ofopposite tubes when in rotating position.Table 2 shows the relationship between the diameter ofswing, ref and rpm.6.3 Oven, explosion-proof, capable of maintaining a tem-perature of
26、105 6 3C.6.4 Balance, having a sensitivity of 0.5 mg for weighing the100-mL beaker and centrifuge tube, and a balance having asensitivity of 0.1 g for weighing the oil sample.FIG. 1 ASTM Cone-Shaped Centrifuge TubeTABLE 1 Calibration Tolerances of Cone-Shaped Centrifuge TubeRange, mLSmallest ScaleDi
27、vision, mLMaximum ScaleError, mL0to0.1 0.05 60.02Over 0.1 to 0.3 0.05 60.03Over 0.3 to 0.5 0.05 60.05Over 0.5 to 1.0 0.1 60.05Over 1.0 to 2.0 0.1 60.10Over 2.0 to 3.0 0.2 60.10Over 3.0 to 5.0 0.5 60.20Over 5.0 to 10.0 1.0 60.50Over 10 to 25 5.0 61.0Over 25 to 100 25.0 61.0TABLE 2 Rotation Speeds for
28、 Centrifuges of Various Diametersof SwingDiameter of Swing, mmArpm at 600 rcf rpm at 700 rcf483 1490 1610508 1450 1570533 1420 1530559 1390 1500AMeasured in millimetres between tips of opposite tubes when in rotatingposition.D 893 05a27. Reagents and Solvents7.1 Purity of ReagentsReagent grade chemi
29、cals 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.3Other grades may beused, provided it is first ascertained
30、 that the reagent is ofsufficiently high purity to permit its use without lessening theaccuracy of the determination.7.2 Purity of WaterUnless otherwise indicated referencesto water shall be understood to mean water in accordance withSpecification D 1193, Type IV.7.3 nbutyl diethanolamine (2,21 (but
31、ylimino) diethanol).(WarningMay be harmful if inhaled or swallowed.)7.4 Ethanol, denaturedconforming to either Formula 30or 3A of the U.S. Bureau of Internal Revenue. (WarningFlammable. Denatured. Cannot be made nontoxic.)7.5 Pentane(WarningExtremely flammable. Vaporsmay cause flash fires.)7.6 Propa
32、n2ol (isopropyl alcohol)(WarningFlammable. Denatured. Cannot be made nontoxic.)7.7 Toluene(WarningFlammable. Vapor harmful.)7.8 Toluene-Alcohol Solution, wash solvent, made by mix-ing 1 volume of toluene (7.7) with 1 volume of denaturedethanol conforming to either Formula No. 30 or 3A of the U.S.Bur
33、eau of Internal Revenue. (WarningFlammable. Dena-tured. Cannot be made nontoxic.)7.9 Pentane-Coagulant SolutionAdd 50 mL of n-butyldiethanolamine (WarningFlammable) and 50 mL of isopro-pyl alcohol (2-propanol) (WarningAs used oil may changeappreciably in storage, samples should be tested as soon asp
34、ossible after removal from the lubricating system and thedates of sampling and testing should be noted) to 1 L ofn-pentane (WarningMay be harmful if inhaled or swal-lowed) and mix.8. Sampling8.1 Obtain a sample using either Practice D 4057 or D 4177.8.2 Heat the sample of used oil to 60 6 5C in the
35、originalcontainer and agitate until all sediment is homogeneouslysuspended in the oil. If the original container is of opaquematerial, or if it is more than three-fourths full, transfer theentire sample to a clear glass bottle having a capacity at leastone third greater than the volume of the sample
36、, and transfer alltraces of sediment from the original container to the bottle byviolent agitation of portions of the sample in the originalcontainer. After complete suspension of all sediment, strain thesample or a convenient aliquot through a 150-m (No. 100)sieve to remove large contaminating part
37、icles.NOTE 2When the sample is clear and transparent and visibly free ofsediment, the straining procedure described above can be omitted.9. Procedure A for Pentane and Toluene InsolublesWithout Coagulant9.1 Pentane Insolubles:9.1.1 Dry a clean centrifuge tube for 30 min at 105 6 3C,cool in a desicca
38、tor, and weigh to the nearest 1 mg. Weigh 10.06 0.1 g of the prepared sample of used oil into the tube and fillto the 100-mL mark with pentane (WarningMay be harmfulif inhaled or swallowed.). Stopper the tube and shake until themixture is homogeneous. Do not allow the mixture to standmore than 3 h.9
39、.1.2 Remove the stopper, and using a wash bottle having afine jet, wash all insolubles from the stopper into the centrifugetube with a minimum of pentane. Balance the weights of eachpair of filled centrifuge tubes, place them in the centrifuge onopposite sides of the head, and centrifuge for 20 6 1
40、min at arate calculated in accordance with 6.2, sufficient to produce arelative centrifugal force (rcf) between 600 and 700 at the tipsof the whirling tubes. (See Table 2.) Carefully decant thesupernatant liquid without disturbing or dispersing the precipi-tate, leaving not more than 3 mL of liquid
41、in the centrifugetube.NOTE 3Due to safety concerns when handling flammable materials,some laboratories have found it suitable to use refrigerated or explosion-proof centrifuges or hermetically sealed centrifuge cups with screw capsand seals.9.1.3 Add 10 6 1 mL of pentane to the tube. Dislodge andbre
42、ak up all of the insolubles from the bottom of the tube bymeans of a clean stiff wire. Wash all insolubles adhering to thewire back into the tube with pentane, filling the tube to the50-mL mark. Stopper the tube and shake until the mixture ishomogeneous. Remove and wash the stopper. Centrifuge for 2
43、06 1 min. Pour the supernatant liquid from the centrifuge tube,using care to avoid disturbing the cake of insolubles in thebottom of the tube.9.1.4 Repeat the entire operation described in 9.1.3.9.1.5 Dry the centrifuge tube containing the washed precipi-tate for 30 min at 105 6 3C, cool in desiccat
44、or, and weigh tothe nearest 1 mg.9.1.6 With relatively heavy precipitates there can be somespattering if the tube is placed directly from the centrifuge intothe oven. In such cases, the precipitate may be partially driedby weathering at room or slightly higher temperatures beforebeing placed in the
45、oven.9.2 Toluene Insolubles:9.2.1 Starting with a fresh sample of used oil, precipitateand centrifuge the pentane insolubles as described in 9.1.1-9.1.4, but do not dry the insolubles in the centrifuge tube.9.2.2 Add 10 6 1 mL of toluene-alcohol solution. Break upand dislodge all of the insolubles f
46、rom the bottom of thecentrifuge tube by means of a clean, stiff wire. Wash anyinsolubles adhering to the wire back into the tube withtoluene-alcohol solution, using a sufficient amount of thissolvent to fill the tube to the 50-mL mark. Stopper the tube andshake until the mixture is homogeneous. Remo
47、ve the stopperand wash the adhering insolubles back into the tube with aminimum amount of toluene. Centrifuge until no visibleinsolubles remain in suspension in the solvent; 10 to 20 min are3Reagent Chemicals, American Chemical Society Specifications, AmericanChemical Society, Washington, DC. For su
48、ggestions 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.D 893 05a3usually sufficien
49、t. Decant the clear solution, taking care not todisturb the precipitate.9.2.3 Repeat the washing procedure described in 9.2.2,substituting toluene for the toluene-alcohol solution.9.2.4 Dry for1hat1056 3 C, cool in a desiccator, andweigh to the nearest 1 mg.10. Procedure B for Coagulated Pentane and TolueneInsolubles10.1 Coagulated Pentane InsolublesProceed in accor-dance with 9.1.1 and 9.1.2, except in 9.1.1 use pentane-coagulant solution (7.9) in place of pentane. Wash the precipi-tate twice with pentane, dry and weigh as directed in 9.
