1、Designation:D342715Designation 31301Standard Test Method forAir Release Properties of Hydrocarbon Based Oils1This standard is issued under the fixed designation D3427;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last r
2、evision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope*1.1 This test method covers the ability of turbine,hydraulic,and gear oils to separate entrained air.NOTE1This test method was devel
3、oped for hydrocarbon based oils.It may be used for some synthetic fluids;however,the precision statementapplies only to hydrocarbon based oils.1.2 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.3 This standard does not purport
4、 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-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D1193 Spec
5、ification for Reagent WaterD1401 Test Method for Water Separability of Petroleum Oilsand Synthetic FluidsD4057 Practice for Manual Sampling of Petroleum andPetroleum ProductsE1 Specification for ASTM Liquid-in-Glass Thermometers2.2 DIN Standard:3DIN 51 3813.Terminology3.1 Definitions of Terms Specif
6、ic to This Standard:3.1.1 air release time,nthe number of minutes needed forair entrained in the oil to reduce in volume to 0.2%under theconditions of this test and at the specified temperature.4.Summary of Test Method4.1 Compressed air is blown through the test oil,which hasbeen heated to a tempera
7、ture of 25 C,50 C,or 75 C.Afterthe air flow is stopped,the time required for the air entrainedin the oil to reduce in volume to 0.2%is recorded as the airrelease time.NOTE2By agreement between the customer and the laboratory,the oilmay be heated at other temperatures.However,the precision at thesedi
8、fferent temperatures is not known at present.5.Significance and Use5.1 Agitation of lubricating oil with air in equipment,suchas bearings,couplings,gears,pumps,and oil return lines,mayproduce a dispersion of finely divided air bubbles in the oil.Ifthe residence time in the reservoir is too short to
9、allow the airbubbles to rise to the oil surface,a mixture of air and oil willcirculate through the lubricating oil system.This may result inan inability to maintain oil pressure(particularly with centrifu-gal pumps),incomplete oil films in bearings and gears,andpoor hydraulic system performance or f
10、ailure.5.2 This test method measures the time for the entrained aircontent to fall to the relatively low value of 0.2%volumeunder a standardized set of test conditions and hence permitsthe comparison of the ability of oils to separate entrained airunder conditions where a separation time is availabl
11、e.Thesignificance of this test method has not been fully established.However,entrained air can cause sponginess and lack ofsensitivity of the control of turbine and hydraulic systems.Thistest may not be suitable for ranking oils in applications whereresidence times are short and gas contents are hig
12、h.6.Apparatus6.1 Aschematic diagram of the apparatus is shown in Fig.1.The component parts are described as follows:6.1.1 Test Vessel,made of borosilicate glass as shown in Fig.2,consisting of a jacketed sample tube fitted with an air inlet1This test method is under the jurisdiction of ASTM Committe
13、e D02 onPetroleum Products,Liquid Fuels,and Lubricants and is the direct responsibility ofSubcommittee D02.C0.02 on Corrosion and Water/Air Separability.Current edition approved Oct.1,2015.Published November 2015.Originallyapproved in 1975.Last previous edition approved in 2014 as D3427 14a1.DOI:10.
14、1520/D3427-15.This standard has been developed through the cooperative effort between ASTMInternational and the Energy Institute,London.The EI and ASTM Internationallogos imply that the ASTM International and EI standards are technicallyequivalent,but does not imply that both standards are editorial
15、ly identical.Adoptedas a joint ASTM/IP standard in 2006.2For 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.3Available
16、 from Beuth Verlag GmbH,Burggrafenstrasse 6,1000 Berlin 30,Germany.*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 States1 capillary,baffle plate,and air outlet tube.The two parts of eachtest vessel should be marked and preferably used as a pair.Interchanged parts may be used so long as the resultant testvessel conforms to the stated dimensions.NOTE3Users are advised to verify t
