1、Designation: D1881 17Standard Test Method forFoaming Tendencies of Engine Coolants in Glassware1This standard is issued under the fixed designation D1881; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A
2、 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 U.S. Department of Defense.1. Scope*1.1 This test method covers a simple glassware test
3、 forevaluating the tendency of engine coolants to foam underlaboratory-controlled-conditions of aeration and temperature.1.2 The values stated in SI units are to be regarded asstandard. The values given in parentheses are approximateequivalents provided for information purposes only.1.3 This standar
4、d 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, health, and environmental practices and deter-mine the applicability of regulatory limitations prior to use.For specific wa
5、rning statements, see Section 7, Materials andReagents.1.4 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recom-mendations issu
6、ed by the World Trade Organization TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D1176 Practice for Sampling and Preparing Aqueous Solu-tions of Engine Coolants orAntirusts for Testing PurposesD1193 Specification for Reagent WaterD3585 Specification for ASTM R
7、eference Fluid for CoolantTestsE1 Specification for ASTM Liquid-in-Glass ThermometersE128 Test Method for Maximum Pore Diameter and Perme-ability of Rigid Porous Filters for Laboratory UseE230/E230M Specification for Temperature-ElectromotiveForce (emf) Tables for Standardized Thermocouples3. Termin
8、ology3.1 Definitions of Terms Specific to This Standard:3.1.1 break time, nthe time required for the foam tocollapse (after the air supply has been shut off) to the firstappearance of an “eye” on the surface of the test solution.3.1.2 eye, nthe appearance of foam free area on thesurface of the test
9、coolant surrounded by a ring of foamclinging to the cylinder walls.4. Summary of Test Method4.1 A solution of coolant and ASTM Type II water is blownwith air at a constant rate for 5 min, while maintained at aconstant temperature of 88 6 1 C (190 6 2 F) by means ofa suitable temperature bath. The vo
10、lume of foam, and the timefor such foam to break, are measured.5. Significance and Use5.1 The test method generally will distinguish coolants thathave a tendency to foam excessively from those that aresuitable for further evaluation to determine performance inactual service.NOTE 1In use, the foaming
11、 tendency of a coolant solution may beincreased by service aging or contamination. A properly functioningpressure cap will tend to suppress foaming in coolant solutions.6. Apparatus6.1 ContainerA 500-mL graduated container of heat-resistant glass, having a diameter of 45 to 50 mm and a lengthof 380
12、mm.6.2 Temperature BathAheat resistant glass container largeenough to permit immersion of the graduated container at leastto the 350 mL graduation mark. A 4000-mL beaker is satisfac-tory.6.3 Heat SourceAny heating system capable of maintain-ing a uniform bath temperature 61C (62 F). A750-wattelectri
13、c hot-plate is satisfactory.1This test method is under the jurisdiction of ASTM Committee D15 on EngineCoolants and Related Fluids and is the direct responsibility of SubcommitteeD15.06 on Glassware Performance Tests.Current edition approved Nov. 1, 2017. Published December 2017. Originallyapproved
14、in 1961 as D1881 61 T. Last previous edition approved in 2009 asD1881 97(2009). DOI: 10.1520/D1881-17.2For 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
15、Document Summary page onthe ASTM website.*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 StatesThis international standard was developed in accordance with internationally reco
16、gnized principles on standardization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.16.4 Aerator TubeA 25.4-mm (1-in.) diameter sphericalgas-diffuse
17、r stone3made of fused crystalline alumina grainwhich meets the following specifications when tested inaccordance with the method given in Annex A1:Maximum pore diameter, m Not greater than 80Permeability at a pressureof 2.45 kPa, mL of air/min3000 to 64006.5 Temperature Measuring Instrument (Environ
18、mentallySafe Thermometer or Thermocouple)An ASTM Partial Im-mersion Temperature Measuring Instrument having a rangefrom 20 to +150 C (0 to 302 F) and conforming to therequirements for Thermometer 1C (1F) as prescribed in Speci-fication E1 or Thermocouple as summarized in SpecificationE230/E230M.6.6
19、Air SupplyA clean and dry source, free from greaseand other contaminants, capable of maintaining the prescribedflow rate through the diffuser stone.6.7 TimerAstop watch or suitable timing device, accurateto 60.2 s.6.8 VentA three-way stopcock inserted in the metered airsupply line immediately ahead
20、of the aerator tube.6.9 Typical Assembly Set-UpA typical apparatus using ahot-plate heat source is shown in Fig. 1.7. Materials and Reagents7.1 Purity of WaterUnless otherwise indicated, referencesto water means reagent water as defined by Type II ofSpecification D1193.7.2 Acetone, for flushing and
21、drying the test equipment.(WarningAcetone is extremely flammable.)7.3 Specification D3585 Test CoolantUnless otherwiseindicated, references to the reference test coolant meansSpecification D3585 coolant prepared without antifoam(Pluronic L-61) as defined in Specification D3585.7.4 Cleaning BathRefer
22、s to an acid or base cleaningsolution used to clean glassware between tests. The choice ofcleaning baths depends on individual needs. For example,Nochromix and alcoholic sodium (potassium) hydroxide arecommon acid and base cleaning baths, respectively.4(WarningThe cleaning baths are strong oxidants
23、and strongacid and base, respectively. Avoid contact with skin, eyes, andclothing. Do not breathe vapor. Handle in a fume hood.)8. Test Solution8.1 A 33 % by volume solution of reference coolant (Speci-fication D3585 test coolant without antifoam) shall be preparedwith the proper quantity of Type II
24、 water.8.2 Prepare a 33 % by volume solution of the coolant to betested with Type II water. Use the same glassware used toprepare the reference coolant test solution. Rinse the glasswarewith Type II water between preparations.Additive concentratesshall be diluted with Type II water to recommended us
25、econcentration. Preparation of the sample shall be done inaccordance with treatment of mixtures described in PracticeD1176. Thus, any insoluble materials will be included in therepresentative sample.9. Test Conditions9.1 Test TemperatureThe temperature bath shall be kept ata constant volume (350 to
26、375 mL mark of the graduatedcylinder) throughout the test. The test solution shall be main-tained at 88 6 1 C (190 6 2 F) throughout. This temperatureis suitable for both high-boiling and low-boiling coolants.9.2 Aeration RateThe aeration rate shall be 1000 6 25mL/min.9.3 Number of TestsThe referenc
27、e coolant shall be testedto determine if the glassware and testing equipment is con-taminated with residue defoamer. If the reference coolant givesa foam volume of greater than 250 mL and a break time ofgreater than 8 s, drain the reference coolant from the glassware,rinse with Type II water and use
28、 for the preparation of the testcoolant.3For information on aerator supplier and specifications, contactASTM Subcom-mittee D15.06 through ASTM International Headquarters.4Nochromix is an inorganic oxidizer that contains no metallic ions. The whitepowder is dissolved in water and mixed with concentra
29、ted sulfuric acid, giving asolution that reportedly is more strongly oxidizing than chromic acid.The sole source of supply of Nochromix known to the committee at this time isGodax Laboratories Inc., 720B Erie Ave., Takoma Park, MD 20912. If you areaware of alternative suppliers, please provide this
30、information to ASTM Interna-tional Headquarters. Your comments will receive careful consideration at a meetingof the responsible technical committee,1which you may attend.FIG. 1 Schematic Drawing of Apparatus for Glassware FoamTestD1881 1729.3.1 Each test coolant shall be tested in triplicate, using
31、 afreshly prepared test solution (Section 8) for each test. Theentire container and aerator tube (see 6.1 and 6.4) shall becleaned scrupulously between each test. The container shall becleaned in cleaning bath and the aerator tube shall be immersedfirst in acetone and flushed back and forth, and the
32、n in waterand flushed back and forth, using vacuum and air pressure. Theentire assembly shall be thoroughly rinsed with Type II waterbefore each test.NOTE 2Scrupulously cleaning of the glassware, aerator tube anddiffuser stone between tests will reduce the potential carry-over ofantifoam from previo
33、us test or glassware detergents that can interfere withtest reproducibility.10. Procedure10.1 Heat 145 mL of solution to 88 C (190 F) in thecontainer positioned in the temperature bath. Immerse theaerator tube and read the level of the liquid to the nearest 5 mL.Measure the temperature with the ther
34、mometer inside thegraduated container.10.2 Connect air supply, position stopcock to permit air flowto aerator tube, and adjust the air flow rate of 1000 mL/minusing a manometer or other suitable instrument for accuratelymeasuring volumes of air flow.10.3 If the volume of the test solution drops as a
35、 result ofevaporation, replenish the test solution to its original volumeusing Type II water before initiating aeration. Measure thetemperature of the test solution at the start of aeration.10.4 The timing of the 5-min aeration period shall start atthe appearance of the first bubbles in the test sol
36、ution.10.5 At the end of 5 min, measure the volume of foam at thehighest level and subtract the initial volume read after insertingthe aerator tube. Read the foam volume to the nearest 5-mLgraduation.10.6 Relieve the air pressure by positioning the three-waystopcock to shut off the air supply and ve
37、nt the inlet tube to theatmosphere simultaneously, and record precisely (60.2 s) thetime for the foam to collapse to the first appearance of an “eye”on the surface of the test solution.11. Report11.1 The testing shall be done in triplicate, using a freshlyprepared solution for each test run. The rep
38、ort shall include thetest results tabulated as follows:“Break Time”Foam Volume AppearanceTest Run at 5 min of “Eye”1 _mL _s2 _mL _s3 _mL _sAverage _mL _s12. Precision and Bias12.1 A statement on precision is under review, and roundrobin testing is currently in progress.13. Keywords13.1 engine coolan
39、ts; foaming; glasswareANNEX(Mandatory Information)A1. TEST FOR MAXIMUM PORE DIAMETER AND PERMEABILITY OF STONE DIFFUSERS(Based on Test Method E128, Specification E1)A1.1 DefinitionsA1.1.1 maximum pore diameterthe diameter in microme-tres of a capillary of circular cross section which is equivalent(w
40、ith respect to surface tension effects) to the largest pore inthe diffuser under consideration.A1.1.2 permeabilitythe flow of air, in millilitres per min-ute through the diffuser stone at air pressure of 2.5 kPa(250 mm of water).A1.2 ApparatusA1.2.1 Apparatus for the maximum pore diameter determi-na
41、tion consists of a regulated source of clean, dry, compressedair; a U-tube water manometer of sufficient length to read apressure differential of 800 mm; and a cylinder of a sizesufficient (250 mL is suitable) to conveniently immerse adiffuser stone to a depth of 100 mm.A1.2.2 Additional apparatus f
42、or permeability determinationconsists of a gas volume meter of sufficient capacity to measureflow rates of at least 6000 mL/min, and a filtering flask largeenough that 25.4-mm (1-in.) diameter diffuser stones will passthrough the neck. The flask shall be fitted with a rubber stopperwith a single hol
43、e to admit the air-inlet tube (see Fig. A1.1).A1.3 ProcedureA1.3.1 Maximum Pore DiameterSupport the clean dif-fuser by an air-inlet tube at a depth of 100 mm as measured tothe top of the stone in distilled water in a cylinder and allow itto soak for at least 2 min. Connect the air-inlet tube to acon
44、trollable source of clean, compressed air and a manometeras shown in Fig. A1.2. Increase the air pressure at a rate ofabout 50 mm of water/min until the first dynamic bubble passesthrough the filter and rises through the water. The first dynamicbubble is recognized by being followed by a succession
45、ofD1881 173additional bubbles. Read the water level in both legs of themanometer and record the difference as the pressure, p. Theuniformity of distribution of pores approaching maximum poresize may be observed by gradually increasing the air pressureand noting the uniformity with which streams of b
46、ubbles aredistributed over the surface.Calculate maximum pore diameter, D, in micrometres, asfollows:D 5 29225/p 2 100! (A1.1)where:p = pressure, mm.A1.3.2 PermeabilityConnect the clean, dry diffuser stoneto a controllable source of clean, dry, compressed air and placeit in a filtering flask connect
47、ed to a suitable flowmeter as shownin Fig. A1.1. Adjust the pressure differential to 2.5 kPa (250mm of water) and measure the rate of flow of air through thediffuser stone in millilitres per minute. Depending on thesensitivity of the flowmeter used, this observation may bemade for a suitably longer
48、period and the average flow rate perminute recorded.SUMMARY OF CHANGESCommittee D15 has identified the location of selected changes to this standard since the last issue(D188197(2009) that may impact the use of this standard.(1) Corrected section reference in Subsection 1.3.(2) Added Specification E
49、230/E230M to Referenced Docu-ments 2.1.(3) Revised Subsection 6.5.(4) Revised Fig. 1.ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical commit
