1、Designation: D893 14Standard Test Method forInsolubles in Used Lubricating Oils1This standard is issued under the fixed designation D893; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in parent
2、heses 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. Scope*1.1 This test method covers the determination of pentaneand toluene
3、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 covers the determination of inso
4、lubles 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 1Results obtained by Procedures A
5、 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 be regarded asstandard. No
6、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 determine the applica-bilit
7、y of regulatory limitations prior to use. For specificwarning statements, see Section 7 and 9.1.1.2. Referenced Documents2.1 ASTM Standards:2D1193 Specification for Reagent WaterD4057 Practice for Manual Sampling of Petroleum andPetroleum ProductsD4177 Practice for Automatic Sampling of Petroleum an
8、dPetroleum Products3. Terminology3.1 Definitions:3.1.1 coagulate, vto cause to become viscous or thickenedinto a coherent mass.3.1.2 coagulated pentane insolubles, nin used oilanalysis, separated matter that results when a coagulant isadded to a solution of used oil in pentane.3.1.2.1 DiscussionThe
9、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 in pentane ortoluene.3.1.4 pentane i
10、nsolubles, 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 not soluble in toluene.3.1.6 used oil
11、, 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 This Standard:3.2.1 insoluble resins
12、, 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 representative sample of used lubrica
13、t-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 tolueneinsolubles, a separate sample of the oil is mixed with pentaneand then centrifuged. The precipitate is washed twice
14、 with1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility ofSubcommittee D02.06 on Analysis of Lubricants.Current edition approved May 1, 2014. Published May 2014. Originallyapproved in 1967. Last previo
15、us edition approved in 2012 as D893 12. DOI:10.1520/D0893-14.2For 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.
16、*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 States1pentane, once with toluene-alcohol solution, and once withtoluene. The insoluble material is then dried and weighed togiv
17、e 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 of the
18、 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 insolubles can
19、 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 (3) eng
20、ine 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 characteris
21、tics 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 constricted in
22、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 at20 C.6.2 Centrifuge, meeting all safety requirements for normaluse and capable of whirling two or more filled centri
23、fuge 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 of bei
24、ng 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:Speed,
25、 rpm 5 1337 =rcf/d (1)where:rcf = relative centrifugal force, andd = diameter swing, mm, measured between tips of oppo-site tubes when in rotating position.Table 2 shows the relationship between the diameter ofswing, ref and rpm.6.3 Oven, either explosion-proof, Class A, safety rated, orsolvent vent
26、ing, capable of maintaining a temperature of105 C 6 3 C.FIG. 1 ASTM Cone-Shaped Centrifuge TubeTABLE 1 Calibration Tolerances of Cone-Shaped Centrifuge TubeRange, mLSmallest ScaleDivision, mLMaximum ScaleError, mL0 to 0.1 0.05 0.02Over 0.1 to 0.3 0.05 0.03Over 0.3 to 0.5 0.05 0.05Over 0.5 to 1.0 0.1
27、 0.05Over 1.0 to 2.0 0.1 0.10Over 2.0 to 3.0 0.2 0.10Over 3.0 to 5.0 0.5 0.20Over 5.0 to 10.0 1.0 0.50Over 10 to 25 5.0 1.0Over 25 to 100 25.0 1.0TABLE 2 Rotation Speeds for Centrifuges of Various Diametersof SwingDiameter of Swing, mmArpm at 600 rcf rpm at 700 rcf483 1490 1610508 1450 1570533 1420
28、1530559 1390 1500AMeasured in millimetres between tips of opposite tubes when in rotating position.D893 1426.4 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.7. Reagents and Solvents7.1
29、 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,where such specifications are available.3Other grades may be
30、used, provided it is first ascertained 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 D1193, Type IV
31、.7.3 nbutyl diethanolamine (2,21 (butylimino) 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. V
32、aporsmay cause flash fires.)7.6 Propan2ol (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 eithe
33、r Formula No. 30 or 3A of the U.S.Bureau 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,
34、 samples should be tested as soon aspossible 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 D4057 or D4177.8.2 If the orig
35、inal container is of opaque material, or if it ismore than three-fourths full, transfer the entire sample to aclear glass bottle having a capacity at least one third greaterthan the volume of the sample, and transfer all traces ofsediment from the original container to the bottle by violentagitation
36、 of portions of the sample in the original container.Heat the sample of used oil at 60 C 6 5 C for 30 min 61 min and agitate until all sediment is homogeneously sus-pended in the oil. After complete suspension of all sediment,strain the sample or a convenient aliquot through a 150 m(No. 100) sieve t
37、o remove large contaminating particles.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
38、min 6 1 min at105 C 6 3 C, cool in a desiccator, and weigh to the nearest1 mg. Weigh 10.0 g 6 0.1 g of the prepared sample of used oilinto the tube and fill to the 75 mL mark with pentane(WarningMay be harmful if inhaled or swallowed.). Stopperthe tube and shake until the mixture is homogeneous. Do
39、notallow the mixture to stand more than 3 h.9.1.2 Remove the stopper, and using a wash bottle having afine jet, wash all insolubles from the stopper with pentane intothe centrifuge tube and bring the solvent level up to the 100 mLmark. Arrange the tubes symmetrically about the centrifuge tominimize
40、imbalance. In the event of an odd number of tubes,using water, fill a dummy tube to the same mass as the sampleto balance the odd tube, and centrifuge for 20 min 6 1 min ata rate calculated in accordance with 6.2, sufficient to produce arelative centrifugal force (rcf) between 600 and 700 at the tip
41、sof the whirling tubes. (See Table 2.) Carefully decant thesupernatant liquid without disturbing or dispersing theprecipitate, leaving not more than 3 mL of liquid in thecentrifuge tube.NOTE 3Due to safety concerns when handling flammable materials,some laboratories have found it suitable to use ref
42、rigerated or explosion-proof centrifuges or hermetically sealed centrifuge cups with screw capsand seals.9.1.3 Add 10 mL 6 1 mL of pentane to the tube. Dislodgeand break up all of the insolubles from the bottom of the tubeby means of a clean stiff wire. Wash all insolubles adhering tothe wire back i
43、nto the tube with pentane, filling the tube to the25 mL mark. Stopper the tube and shake until the mixture ishomogeneous. Remove and wash the stopper with pentane,filling the tube to the 50 mL mark. Centrifuge for 20 min 61 min. Pour the supernatant liquid from the centrifuge tube,using care to avoi
44、d 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 6 1 min at 105 C 6 3 C, cool in desiccator,and weigh to the nearest 1 mg.9.1.6 With relatively heavy precipita
45、tes 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 oven.9.2 Toluene Insolubles:9.2.1 Starting with a fresh sample of used
46、 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.3Reagent Chemicals, American Chemical Society Specifications, AmericanChemical Society, Washington, DC. For suggestions on the testing of reagents notlisted by the
47、 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.D893 1439.2.2 Add 10 mL 6 1 mLof toluene-alcohol solution. Breakup and dislodge
48、all of the insolubles from 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 25 mL mark. Stopper the tube andshake until the mixtu
49、re is homogeneous. Remove the stopperand wash the adhering insolubles back into the tube withtoluene-alcohol solution, and bring the total volume to 50 mL.Centrifuge for 20 min 6 1 min. Decant the clear solution,taking care not to disturb 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 for 60 min 6 1 min at 105 C 6 3 C, cool in adesiccator, and weigh to the nearest 1 mg.10. Procedure B for Coagulated Pentane and TolueneInsolubles10.1 Coa
