1、Designation:D190308(Reapproved 2017)Standard Practice forDetermining the Coefficient of Thermal Expansion ofElectrical Insulating Liquids of Petroleum Origin,andAskarels1This standard is issued under the fixed designation D1903;the number immediately following the designation indicates the year ofor
2、iginal adoption 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.1.Scope1.1 This practice covers the determination of the coef-ficientof thermal
3、 expansion of electrical insulating liquids of petro-leum origin,and askarels,containing PCBs(polychlorinatedbiphenyls),when used as an insulating or cooling medium,orboth,in cables,transformers,oil circuit breakers,capacitors,orsimilar apparatus.1.2 The values stated in SI units are to be regarded
4、asstandard.No other units of measurement are included in thisstandard.1.3 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 ap
5、plica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D941 Test Method for Density and Relative Density(Spe-cific Gravity)of Liquids by Lipkin Bicapillary Pycnom-eter(Withdrawn 1993)3D1250 Guide for Use of the Petroleum Measurement TablesD1298 Test Method for
6、Density,Relative Density,or APIGravity of Crude Petroleum and Liquid Petroleum Prod-ucts by Hydrometer MethodD1810 Test Method for Specific Gravity of Askarels(With-drawn 2001)33.Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 coeffcient of thermal expansion of a liquid,nthechang
7、e in volume per unit volume per degree change intemperature.It is commonly stated as the average coefficientover a given temperature range.4.Significance and Use4.1 Knowledge of the coefficient of thermal expansion of aliquid is essential to compute the required size of a container toaccommodate a v
8、olume of liquid over the full temperaturerange to which it will be subjected.It is also used to computethe volume of void space that would exist in an inelastic devicefilled with the liquid after the liquid has cooled to a lowertemperature.5.Procedure for Liquids of Petroleum Origin5.1 The coefficie
9、nt of thermal expansion used in GuideD1250,is 0.00040/F for the temperature range from 17.7 to65.5C(0 to 150F),and petroleum oils ranging from 15.0 to34.9API gravity or 0.9659 to 0.8504 relative density(specificgravity).In the preparation of these tables for relative density(specific gravity)values
10、above 0.600,it has been assumed forpurposes of standardization that all crude petroleum andpetroleum products have uniform coefficients of expansion inthe same temperature ranges.When the required accuracy ofresults falls within these assumptions,this value for coefficientof expansion may be used.5.
11、2 If closer approximation than that indicated in 5.1 isrequired,the coefficient of thermal expansion may be calcu-lated by determining observed relative densities(specificgravities).Determine the relative densities at any two tempera-tures below 90C(194F)and not less than 5C(9F),normore than 14C(25F
12、)degrees apart by Practice D1298.Thedifference in the observed relative densities at the two tem-peratures divided by the product of the relative density at thelower temperature and the difference in the two temperaturesmay be used as the average coefficient of expansion for theobserved temperature
13、range.6.Procedure for Askarels6.1 Determine the relative density(specific gravity)of theaskarel at any two convenient temperatures below 90C1This practice is under the jurisdiction of ASTM Committee D27 on ElectricalInsulating Liquids and Gasesand is the direct responsibility of SubcommitteeD27.07 o
14、n Physical Test.Current edition approved Jan.1,2017.Published February 2017.Originallyapproved in 1961.Last previous edition approved in 2008 as D1903 08.DOI:10.1520/D1903-08R17.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For
15、Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.3The last approved version of this historical standard is referenced onwww.astm.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United St
16、atesThis international standard was developed in accordance with internationally recognized 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.1(194F)and not less than 14C(25F)apart by Test MethodD1810.The difference in the observed relative densities at thetwo temperatures divided by the product of the relative densityat t
