1、Designation: D892 131D892 18 British Standard 5092Designation: 146/2000Standard Test Method forFoaming Characteristics of Lubricating Oils1This standard is issued under the fixed designation D892; the number immediately following the designation indicates the year oforiginal adoption or, in the case
2、 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.This standard has been approved for use by agencies of the U.S. Department of Defense.1 NOTEA section re
3、ference in 12.1 was corrected editorially in June 2016.1. Scope*1.1 This test method covers the determination of the foaming characteristics of lubricating oils at 24 C and 93.5 C. Means ofempirically rating the foaming tendency and the stability of the foam are described.1.2 WARNINGMercury has been
4、 designated by many regulatory agencies as a hazardous material that can cause centralnervous system, kidney and liver damage. Mercury, or its vapor, may be hazardous to health and corrosive to materials. Cautionshould be taken when handling mercury and mercury containing products. See the applicabl
5、e product Material Safety Data Sheet(MSDS) for details and EPAs websitehttp:/www.epa.gov/mercury/faq.htmfor additional information. Users should be awarethat selling mercury and/or mercury containing products into your state or country may be prohibited by law.1.3 The values stated in SI units are t
6、o be regarded as the standard.The values given in parentheses are for information only.afterSI units are provided for information only and are not considered standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof
7、 the user of this standard to establish appropriate safety safety, health, and healthenvironmental practices and determine theapplicability of regulatory limitations prior to use. For specific warning statements, see Sections 7, 8, and 9.1.1.1.5 This international standard was developed in accordanc
8、e with internationally recognized principles on standardizationestablished in the Decision on Principles for the Development of International Standards, Guides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standa
9、rds:2D445 Test Method for Kinematic Viscosity of Transparent and Opaque Liquids (and Calculation of Dynamic Viscosity)D6082 Test Method for High Temperature Foaming Characteristics of Lubricating OilsE1 Specification for ASTM Liquid-in-Glass ThermometersE128 Test Method for Maximum Pore Diameter and
10、 Permeability of Rigid Porous Filters for Laboratory UseE1272 Specification for Laboratory Glass Graduated Cylinders3. Terminology3.1 Definitions:3.1.1 diffuser, nfor gas, a device for dispersing gas into a fluid.3.1.1.1 Discussion1 This test method is under the jurisdiction ofASTM Committee D02 on
11、Petroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility of SubcommitteeD02.06 on Analysis of Liquid Fuels and Lubricants.Current edition approved June 15, 2013April 15, 2018. Published July 2013May 2018. Originally approved in 1946. Last previous edition approved in 2011201
12、3 asD892 11a.D892 131 DOI:10.1520/D0892-13E01 DOI:10.1520/D0892-18.In the IP, this test method is under the jurisdiction of the Standardization Committee. This test method has been approved by the sponsoring committees and accepted bythe cooperating societies in accordance with established procedure
13、s.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.This document is not an ASTM standard and is intended only
14、to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
15、of the standard as published by ASTM is to be considered the official document.*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 States1In this test method the diffuser may be ma
16、de of either metallic or non-metallic materials.3.1.2 entrained air (or gas), nin liquids, a two-phase mixture of air (or gas) dispersed in a liquid in which the liquid is themajor component on a volumetric basis.3.1.2.1 DiscussionEntrained air (or gas) may form micro size bubbles in liquids that ar
17、e not uniformly dispersed and that may coalesce to form largerbubbles below or at the surface which break or form foam.3.1.3 foam, nin liquids, a collection of bubbles formed in or on the surface of a liquid in which the air or gas is the majorcomponent on a volumetric basis.3.1.4 lubricant, nany ma
18、terial interposed between two surfaces that reduces friction or wear between them. D60823.1.4.1 DiscussionIn this test method, the lubricant is an oil which may or may not contain additives such as foam inhibitors.3.1.5 maximum pore diameter, nin gas diffusion, the diameter of a circular cross-secti
19、on of a capillary is equivalent to thelargest pore of the diffuser under consideration.3.1.5.1 DiscussionThe pore dimension is expressed in micrometres (m).3.1.6 permeability, nin gas diffusion, the rate of a substance that passes through a material (diffuser) under given conditions.3.2 Definitions
20、of Terms Specific to This Standard:3.2.1 dynamic bubble, nthe first bubble to pass through and escape from the diffuser followed by a continuous succession ofbubbles when testing for the maximum pore diameter in Annex A1.3.2.1.1 DiscussionWhen a diffuser is immersed in a liquid, air can be trapped i
21、n the pores. It can escape eventually or as soon as a pressure is appliedto the diffuser. When testing for maximum pore diameter (Annex A1) the escape of such bubble shall be ignored.3.2.2 foam stability, nin foam testing, the amount of foam remaining at the specified time following the disconnectin
22、g of theair supply.3.2.2.1 DiscussionIn this test method, foam stability is determined from measurements made 10 min 6 10 s after disconnecting the air supply. Incases after the air supply has been disconnected, where the foam collapses to 0 mL before the 10 min settling time has elapsed,the test ma
23、y be terminated and the foam stability result recorded as 0 mL.3.2.3 foaming tendency, nin foam testing, the amount of foam determined from measurements made immediately after thecessation of air flow.4. Summary of Test Method4.1 Sequence IA portion of sample, maintained at a bath temperature of 24
24、C 6 0.5 C is blown with air at a constant rate(94 mLmin 6 5 mLmin ) for 5 min, then allowed to settle for 10 min (unless the case described in 3.2.2.1 applies, in which case,the time duration can be shortened). The volume of foam is measured at the end of both periods.4.2 Sequence IIAsecond portion
25、of sample, maintained at a bath temperature of 93.5 C 60.5 C, 6 0.5 C, is analyzed usingthe same air flow rate and blowing and settling time duration as indicated in 4.1.4.3 Sequence IIIThe sample portion used in conducting Sequence II is used for Sequence III, where any remaining foam iscollapsed a
26、nd the sample portion temperature cooled below 43.5 C by allowing the test cylinder to stand in air at roomtemperature, before placing the cylinder in the bath maintained at 24 C 6 0.5 C. The same air flow rate and blowing and settlingtime duration as indicated in 4.1 is followed.D892 1825. Signific
27、ance and Use5.1 The tendency of oils to foam can be a serious problem in systems such as high-speed gearing, high-volume pumping, andsplash lubrication. Inadequate lubrication, cavitation, and overflow loss of lubricant can lead to mechanical failure. This testmethod is used in the evaluation of oil
28、s for such operating conditions.6. Apparatus6.1 Foaming Test Apparatus, an example of a suitable set-up is shown in Fig. 1, consisting of a 1000 mL graduated cylinderor cylinders (meeting Specification E1272 class B tolerance requirement of 66 mL and at least graduations of 10 mL) held inposition wh
29、en placed in the baths, such as fitted with a heavy ring or clamp assembly to overcome the buoyancy, and an air-inlettube, to the bottom of which is fastened a gas diffuser. The gas diffuser can be either a 25.4 mm (1 in.) diameter spherical gasdiffuser stone made of fused crystalline alumina grain,
30、 or a cylindrical metal diffuser made of sintered five micron porous stainlesssteel (Note 1). The cylinder shall have a diameter such that the distance from the inside bottom to the 1000 mL graduation markis 360 mm 6 25 mm. It shall be circular at the top (Note 2) and shall be fitted with a stopper,
31、 such as those made of rubber, havingone hole at the center for the air-inlet tube and a second hole off-center for an air-outlet tube. The air-inlet tube shall be adjustedso that, when the stopper is fitted tightly into the cylinder, the gas diffuser (Note 3) just touches the bottom of the cylinder
32、 andis approximately at the center of the circular cross section. Gas diffusers shall meet the following specification when tested inaccordance with the method given in Annex A1:Maximum pore diameter, m Not greater than 80Permeability at pressure of 2.45 kPa (250 mm) water,mL of air/min3000 to 6000N
33、OTE 1Gas diffuser permeability and porosity can change during use; therefore, it is recommended that diffusers be tested when new and periodicallythereafter preferably after each use.NOTE 2Graduated cylinders with circular tops can be prepared from cylinders with pouring spouts by cutting them off b
34、elow the spouts. The cutsurface is to be smoothed before use by fire polishing or grinding.NOTE 3Gas diffusers may be attached to air-inlet tubes by any suitable means. A convenient arrangement is shown in Fig. 2.NOTE 4It may be necessary to confirm the volume of the cylinder.6.2 Test Baths, large e
35、nough to permit the immersion of the cylinder at least to the 900 mL mark and capable of beingmaintained at temperatures constant to 0.5 C (1 F) at 24 C (75 F) and 93.5 C (200 F), respectively. Both bath (Note 6) andbath liquid shall be clear enough to permit observation of the graduations on the cy
36、linder.NOTE 5Air baths may also be utilized for heating purposes. Limited data has shown that both liquid and air baths give equivalent results. However,the precision estimates given in Section 13 are based on using only liquid baths.3NOTE 6Heat-resistant cylindrical glass jars approximately 300 mm
37、(12 in.) in diameter and 450 mm (18 in.) in height make satisfactory baths.6.3 Air Supply, from a source capable of maintaining an air flow rate of 94 mLmin 6 5 mLmin through the gas diffuser. Ifthe dew point of the air supply does not meet the 60 C or lower requirements as stated in 7.3, the air sh
38、all be passed througha drying tower 300 mm in height packed as follows: just above the constriction place a 20 mm layer of cotton, then a 180 mm layer3 Supporting data have been filed at ASTM International Headquarters and may be obtained by requesting Research Report RR:D02-1516. Contact ASTM Custo
39、merService at serviceastm.org.FIG. 1 Foaming Test ApparatusD892 183of indicating desiccant, and a 20 mm layer of cotton. The cotton serves to hold the desiccant in place. Refill the tower when theindicating desiccant begins to show presence of moisture. The use of the drying tower described above is
40、 optional if the dew pointof the air supply meets the 60 C or lower requirements as stated in 7.3. A flowmeter sensitive to the required tolerances can beused to measure the air flow (Note 7).NOTE 7A manometer type flowmeter, in which the capillary between the two arms of the U-tube is approximately
41、 0.4 mm in diameter and 16 mmin length, and in which n-butylphthalate is the manometric liquid, is suitable.6.3.1 The total volume of air leaving the foaming test apparatus shall be measured by a volume measuring device (Note 9)capable of accurately measuring gas volumes of about 470 mL. The air sha
42、ll be passed through at least one loop of copper tubingplaced around the inside circumference of the cold bath so that the volume measurement is made at approximately 24 C (75 F).Precautions are to be taken to avoid leaks at any point in the system.NOTE 8Alternatively, a 1 Lcylinder (with 10 mLgradu
43、ation marks) full of water is inverted in a tall, large beaker also filled with water. There shouldbe no air bubbles inside. Air leaving the copper loop in the bath is connected below the cylinder. When the test is started, air will flow into the cylinder,displacing the water. At the end of the test
44、, the volume of air in the cylinder is measured by equalizing the water levels inside and outside the cylinder.Alternatively, the total volume of air passed would be the difference between the final and the initial volumes of water in the cylinder.NOTE 9A wet test meter calibrated in hundredths of a
45、 litre is suitable.6.4 Timer, graduated and accurate to 1 s or better.6.5 Temperature Sensing Device, capable of covering the temperature range from at least 20 C to 100 C, with an accuracy of60.5 C. A thermometer having a range as shown below and conforming to the requirements as prescribed in Spec
46、ification E1 orspecifications for IP thermometers has been found suitable to use:TemperatureRangeThermometerASTM No. IP20 C to 102 C 12C 64C7. Reagents and Materials7.1 Purity of ReagentsReagent grade chemicals shall be used in all cases. Unless indicated otherwise, it is intended that allreagents c
47、onform to the specifications of the committee on Analytical Reagents of the American Chemical Society where suchspecifications are available.4 Other grades may be used, provided it is first ascertained that the reagent is of sufficiently high purityto permit its use without lessening the accuracy of
48、 the determination.7.2 Acetone(WarningExtremely flammable, vapors can cause a flash fire).7.3 Compressed Air, hydrocarbon free and dry to a dew point of 60 C or lower, otherwise the drying tower described in 6.3shall be used.4 Reagent Chemicals, American Chemical Society Specifications, American Che
49、mical Society, Washington, DC. For Suggestions on the testing of reagents not listed bythe American Chemical Society, see Annual Standards for Laboratory Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeia and NationalFormulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville, MD.Dimensions in millimetres (inches)FIG. 2 Attachment of Gas Diffusers to Air-Inlet TubesD892 1847.4 Cleaning Reagentssuch as heptane (WarningFlammable, vapor harmful) and toluene (methylbenzene
copyright@ 2008-2019 麦多课文库(www.mydoc123.com)网站版权所有
备案/许可证编号:苏ICP备17064731号-1