ASTM D7216-2008a 923 Standard Test Method for Determining Automotive Engine Oil Compatibility with Typical Seal Elastomers.pdf

1、Designation: D 7216 08aAn American National StandardStandard Test Method forDetermining Automotive Engine Oil Compatibility withTypical Seal Elastomers1This standard is issued under the fixed designation D 7216; the number immediately following the designation indicates the year oforiginal adoption

2、or, in the case of revision, 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.INTRODUCTIONAny properly equipped laboratory, without outside assistance, can use the tes

3、t method described inthis standard. However, the ASTM Test Monitoring Center (TMC)2provides a reference oil (TMC1006-1) and an assessment of the test results obtained with this oil and the reference elastomers. Bythese means, the laboratory will know whether their use of the test method gives result

4、s statisticallysimilar to those obtained by other laboratories.The TMC also use the reference oil results on different batches of elastomers from differentlaboratories to update continually the total and within-laboratory standard deviation estimates. Somespecifications, for example, Specification D

5、 4485, use the updated TMC standard deviation estimates,pertaining at the time test oils are evaluated, to adjust specification limits for the effects of the industrytest variability.Various agencies require that a laboratory utilize the TMC services in seeking qualification of oilsagainst specifica

6、tions. For example, the U.S. Army imposes such a requirement in connection withseveral Army engine lubricating oil specifications.Accordingly, this test method is written for use by laboratories that utilize the TMC services.Laboratories that choose not to use those services may simply ignore those

7、portions of the test methodthat refer to the TMC.This test method may be modified by means of information letters issued by the TMC. In addition,the TMC may issue supplementary memoranda related to this test method.1. Scope1.1 This test method covers quantitative procedures for theevaluation of the

8、compatibility of automotive engine oils withfive reference elastomers typical of those used in the sealingmaterials in contact with these oils. Compatibility is evaluatedby determining the changes in volume, Durometer A hardnessand tensile properties when the elastomer specimens areimmersed in the o

9、il for a specified time and temperature.1.2 Effective sealing action requires that the physical prop-erties of elastomers used for any seal have a high level ofresistance to the liquid or oil in which they are immersed.When such a high level of resistance exists, the elastomer issaid to be compatibl

10、e with the liquid or oil.NOTE 1The user of this test method should be proficient in the use ofTest Methods D 412 (tensile properties), D 471 (effect of rubber immer-sion in liquids), D 2240 (Durometer hardness), and D 5662 (gear oilcompatibility with typical oil seal elastomers), all of which are in

11、volved inthe execution of the operations of this test method.1.3 This test method provides a preliminary or first orderevaluation of oil/elastomer compatibility only. Because sealsmay be subjected to static or dynamic loads, or both, and theymay operate over a range of conditions, a complete evaluat

12、ionof the potential sealing performance of any elastomer-oilcombination in any service condition usually requires testsadditional to those described in this test method.1.4 The five reference elastomer formulations specified inthis test method were chosen to be representative of those usedin heavy-d

13、uty diesel engines. The procedures described in thistest method can, however, also be used to evaluate thecompatibility of automotive engine oils with different elas-tomer types/formulations or different test durations and tem-peratures to those employed in this test method.1This test method is unde

14、r the jurisdiction of ASTM Committee D02 onPetroleum Products and Lubricants and is the direct responsibility of SubcommitteeD02.B0.07 on Development and Surveillance of Bench Tests Methods.Current edition approved Dec. 1, 2008. Published January 2009. Originallyapproved in 2005. Last previous editi

15、on approved in 2008 as D 721608.2Until the next revision of this test method, the ASTM Test Monitoring Centerwill update changes in the test method by means of information letters. Informationletters may be obtained from theASTM Test Monitoring Center, 6555 PennAvenue,Pittsburgh, PA 15206. (www.astm

16、tmc.cmu.edu) Attention: Administrator. Thisedition incorporates revisions in all information letters through No. 07-1.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.NOTE 2In such cases, the precision and bias statement in Section 12

17、does not apply. In addition to agreeing acceptable limits of precision,where relevant, the user and supplier should also agree: (1) test tempera-tures and immersion times to be used; (2) the formulations and typicalproperties of the elastomers; and (3) the sourcing and quality control of theelastome

18、r sheets.NOTE 3The TMC may also issue Information Letters on this matter.1.5 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.6 This standard does not purport to address all of thesafety concerns, if any, associated with its us

19、e. 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.1.7 This test method is arranged as follows:SectionScope 1Referenced Documents 2Terminology 3Summary of Test Method 4S

20、ignificance and Use 5Apparatus 6Reference Materials 7Procedure 8Calculations 9TMC 1006-1 Reference Oil 10Report 11Precision and Bias 12Keywords 13Formulations and Physical Properties for the Reference Elastomers Annex A12. Referenced Documents2.1 ASTM Standards:3D 297 Test Methods for Rubber Product

21、sChemicalAnalysisD 412 Test Methods for Vulcanized Rubber and Thermo-plastic ElastomersTensionD 471 Test Method for Rubber PropertyEffect of LiquidsD 1193 Specification for Reagent WaterD 1566 Terminology Relating to RubberD 2240 Test Method for Rubber PropertyDurometerHardnessD 4175 Terminology Rel

22、ating to Petroleum, PetroleumProducts, and LubricantsD 4485 Specification for Performance of Engine OilsD 5662 Test Method for Determining Automotive Gear OilCompatibility with Typical Oil Seal ElastomersE29 Practice for Using Significant Digits in Test Data toDetermine Conformance with Specificatio

23、nsE 178 Practice for Dealing With Outlying Observations3. Terminology3.1 Definitions:3.1.1 automotive, adjdescriptive of equipment associatedwith self-propelled machinery, usually vehicles driven byinternal combustion engines. D 41753.1.2 candidate oil, nan oil that is intended to have theperformanc

24、e characteristics necessary to satisfy a specificationand is to be tested against that specification. D 41753.1.3 elastomer, na natural or synthetic polymer havingthe rubber-like property of substantially recovering its size andshape after removal of a deforming force. D 41753.1.4 engine oil, na liq

25、uid that reduces friction or wear, orboth, between the moving parts within an engine; removes heatparticularly from the underside of pistons; and serves ascombustion gas sealant for the piston rings.3.1.4.1 DiscussionIt may contain additives to enhancecertain properties. Inhibition of engine rusting

26、, deposit forma-tion, valve train wear, oil oxidation and foaming are examples.D 41753.1.5 formulation, nthe specific chemical compositionused in manufacturing a seal elastomer or a reference oil.D 56623.1.6 hardness, nof an elastomer, the resistance to defor-mation or indentation.3.1.6.1 Discussion

27、In this test method the hardness of anelastomer is measured with a Shore Durometer A (see TestMethod D 2240). D 41753.1.7 heavy-duty engine, nin internal; combustion enginetypes, one that is designed to allow operation continuously at orclose to its peak output.3.1.7.1 DiscussionThis type of engine

28、is typically in-stalled in large trucks and busses as well as farm, industrial,and construction equipment. D 44853.1.8 non-reference oil, nany oil other than a referenceoil, such as a research formulation, commercial oil or candidateoil. D 41753.1.9 reference oil, nan oil of known performance char-a

29、cteristics, used as a basis for comparison.3.1.9.1 DiscussionReference oils are used to calibratetesting facilities, to compare the performance of other oils, orto evaluate other materials (such as seals) that interact withoils. D 41753.1.10 tensile strength, nthe maximum tensile stress ap-plied in

30、stretching a specimen to rupture. D 15663.1.11 test oil, nany oil subjected to evaluation in anestablished procedure. D 41753.1.12 ultimate elongation, nthe elongation at which rup-ture occurs in the application of continued tensile stress.D 15663.2 Definitions of Terms Specific to This Standard:3.2

31、.1 compatibility, nof an engine oil/elastomer combina-tion, a characteristic that signifies a complete or high-level ofresistance of the elastomer to deleterious effects imparted bycontact with, or immersion in, the oil.3.2.1.1 DiscussionThe phrase “high compatibility” indi-cates that after contact

32、or immersion, the elastomer propertiesare maintained at or near their initial level. The terms “lack ofcompatibility” and “low compatibility” indicate that aftercontact or immersion, the elastomer properties are adverselyaffected to an extent that could be detrimental to sealingperformance.3For refe

33、renced 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.D 7216 08a23.2.2 immersion test, nan operation to evaluate compat-ibil

34、ity by determining the effect of a liquid on elastomer testspecimens submerged in the liquid for a specified time and ata specified temperature.3.2.2.1 DiscussionThe effect of the liquid is evaluated bythe difference in (typical) elastomer physical properties pre-and post-immersion.3.2.3 reference e

35、lastomer, nan elastomer compound pre-pared using a specified formulation; its immersion test prop-erties with selected oils have been well established by the useof recognized and accepted testing and documentation proce-dures.4. Summary of Test Method4.1 Measurements of initial volume, hardness (Dur

36、ometerA) and tensile properties (ultimate elongation and tensilestrength) are made on specimens of specified dimensions cutfrom sheets of reference elastomers. Table 1 shows the types ofelastomers involved.4.2 The elastomer specimens are immersed in both non-reference oil(s) and a reference oil and

37、aged for 336 h atspecified temperatures.4.3 The effects of the test oils on the elastomers aredetermined by measuring the changes in volume, hardness andtensile properties resulting from the immersion in the oil.5. Significance and Use5.1 Some engine oil formulations have been shown to lackcompatibi

38、lity with certain elastomers used for seals in automo-tive engines. These deleterious effects on the elastomer aregreatest with new engine oils (that is, oils that have not beenexposed to an engines operating environment) and when theexposure is at elevated temperatures.5.2 This test method requires

39、 that non-reference oil(s) betested in parallel with a reference oil, TMC 1006-1, known tobe aggressive for some parameters under service conditions.This relative compatibility permits decisions on the anticipatedor predicted performance of the non-reference oil in service.5.3 Elastomer materials ca

40、n show significant variation inphysical properties, not only from batch-to-batch but alsowithin a sheet and from sheet-to-sheet. Results obtained withthe reference oil are submitted by the test laboratories to theTMC to allow it to update continually the total and within-laboratory standard deviatio

41、n estimates. These estimates, there-fore, incorporate effects of variations in the properties of thereference elastomers on the test variability.5.4 This test method is suitable for specification compliancetesting, quality control, referee testing, and research anddevelopment.5.5 The reference elast

42、omers, reference oil and the physicalproperties involved in this test method address the specificrequirements of engine oils. Although other tests exist forcompatibility of elastomers with liquids, these are consideredtoo generalized for engine oils.6. Apparatus6.1 The testing equipment as specified

43、 in Test MethodsD 412, D 471, D 2240, and D 5662 is required for the use ofthis test method.6.2 BalanceUse any commercially available balance ca-pable of weighing to the nearest 0.1 mg. Equip the balance witha suspension hook and a platform to locate a hydrostatic-weighing beaker above the balance p

44、an.6.2.1 CalibrationCalibrate the balance annually as de-scribed in Test Method D 5662.6.3 Hardness Durometer ASee Test Method D 2240. Usea standmounted Durometer.6.3.1 CalibrationCalibrate the hardness Durometer annu-ally as described in Test Method D 2240. Use an outsidesource, with standards trac

45、eable to the National Institute forStandards Technology (NIST), for annual calibration. Performchecks with internal standards weekly. Checks with internalstandards shall be within 63 points. Calibrate internal stan-dards annually, using an outside source, with standards trace-able to NIST.6.4 Tensio

46、n Testing MachineSee the appropriate sectionsof Test Method D 412. The rate of grip separation for thetension testing shall be 8.5 6 0.8 mm/s.6.4.1 CalibrationUsing an outside source, calibrate thetension testing machine annually, as described in Test MethodD 412, using standards traceable to NIST.6

47、.5 Glass TubesPreferably of borosilicate glass, havingan outside diameter of 38 mm and an overall length of 300 mm.Fit each tube loosely with an inert sealing device (such as acork stopper covered with aluminum foil) that will not con-taminate the test oil.6.6 Hanger WireStainless steel, about 0.5 m

48、m diameter,having a suitably sized eye at one end and a hook with anapproximately 8-mm gap at the other, to suspend the elastomertest specimens when measuring their mass in water.6.7 Specimen Suspension WireStainless steel, about 0.8 to1 mm diameter to the shape and dimensions shown in Fig. 1,to hol

49、d the elastomer test specimens submerged in the immer-sion oil. (The specimens are attached to the suspension wirewhich is hung over the edge of the glass tube and held in placeby the stopper as shown in Fig. 2.)6.8 Heated Immersion Test Bath or BlockCapable ofmaintaining the test oil in the glass tube to within 61C of thetest temperature. The immersion test bath or block shallcontain a rack or holes that will accept the glass tubes specifiedin 6.5 and hold them in a vertical position.6.9 Die for Cutting DumbbellsUse Die C as specified inTest