1、Designation: D2140 08 (Reapproved 2017)Standard Practice forCalculating Carbon-Type Composition of Insulating Oils ofPetroleum Origin1This standard is issued under the fixed designation D2140; the number immediately following the designation indicates the year oforiginal adoption or, in the case of
2、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 may be used to determine the carbon-typecomposition of mineral insulating oils by
3、correlation with basicphysical properties. For routine analytical purposes it elimi-nates the necessity for complex fractional separation andpurification procedures. The practice is applicable to oilshaving average molecular weights from 200 to above 600, and0 to 50 aromatic carbon atoms.1.2 Carbon-
4、type composition is expressed as percentage ofaromatic carbons, percentage of naphthenic carbons, andpercentage of paraffinic carbons. These values can be obtainedfrom the correlation chart, Fig. 1, if both the viscosity-gravityconstant (VGC) and refractivity intercept (ri) of the oil areknown. Visc
5、osity, density and relative density (specificgravity), and refractive index are the only experimental datarequired for use of this test method.1.3 This practice is useful for determining the carbon-typecomposition of electrical insulating oils of the types commonlyused in electric power transformers
6、 and transmission cables. Itis primarily intended for use with new oils, either inhibited oruninhibited.1.4 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.5 This standard does not purport to address all of thesafety concerns,
7、 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:2D129 Test Method for Sulfur in Petroleum Pro
8、ducts (Gen-eral High Pressure Decomposition Device Method)D445 Test Method for Kinematic Viscosity of Transparentand Opaque Liquids (and Calculation of Dynamic Viscos-ity)D923 Practices for Sampling Electrical Insulating LiquidsD1218 Test Method for Refractive Index and RefractiveDispersion of Hydro
9、carbon LiquidsD1481 Test Method for Density and Relative Density (Spe-cific Gravity) of Viscous Materials by Lipkin BicapillaryPycnometerD2007 Test Method for Characteristic Groups in RubberExtender and Processing Oils and Other Petroleum-Derived Oils by the Clay-Gel Absorption Chromato-graphic Meth
10、odD2501 Test Method for Calculation of Viscosity-GravityConstant (VGC) of Petroleum OilsD3238 Test Method for Calculation of Carbon Distributionand Structural Group Analysis of Petroleum Oils by then-d-M MethodD4052 Test Method for Density, Relative Density, and APIGravity of Liquids by Digital Dens
11、ity Meter3. Terminology3.1 Definitions:3.1.1 percent of aromatic carbons (% CA)the weightpercent of the total carbon atoms present in an oil that arecombined in aromatic ring-type structures.3.1.2 percent of naphthenic carbons (% CN)the weightpercent of the total carbon atoms present in an oil that
12、arecombined in naphthenic ring-type structures.3.1.3 percent of paraffnic carbons (% CP)the weightpercent of the total carbon atoms present in an oil that arecombined in paraffinic chain-type structures.1This practice is under the jurisdiction of ASTM Committee D27 on ElectricalInsulating Liquids an
13、d Gases and is the direct responsibility of SubcommitteeD27.07 on Physical Test.Current edition approved Jan. 1, 2017. Published February 2017. Originallyapproved in 1963 as D2140 63 T. Last previous edition approved in 2008 asD2140 08. DOI: 10.1520/D2140-08R17.2For referenced ASTM standards, visit
14、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.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959.
15、 United StatesThis 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 Bar
16、riers to Trade (TBT) Committee.1NOTE 1The resolution of carbon atoms into structural classificationsis independent of whether the structures exist as separate molecules or arecombined with other structural forms in a molecule. For example, aparaffinic chain may be either an aliphatic hydrocarbon mol
17、ecule, or maybe an alkyl group attached to an aromatic or naphthenic ring.4. Summary of Practice4.1 A sample of the oil is tested to determine its viscosity,density and relative density (specific gravity), and refractiveindex. From these measured properties the viscosity-gravityconstant (VGC) and re
18、fractivity intercept (ri) are obtained bycalculation, using the equations given. The calculated values ofVGC and riare used with Fig. 1, to correlate those parameterswith carbon-type composition. The composition in terms of %CA,%CN, and % CPmay be read directly from Fig. 1.NOTE 2Fig. 1 is a form of
19、correlation chart that has been foundsatisfactory for use with this method. Other chart forms may be devisedand used in preference to Fig. 1 if it is determined that the data obtainedare consistent with similar data from Fig. 1. In addition, some users willfind it convenient to develop a computer pr
20、ogram or spreadsheet whichwill provide a consistent evaluation of the data.5. Significance and Use5.1 The primary purpose of this practice is to characterizethe carbon-type composition of an oil. It is also applicable inobserving the effect on oil constitution, of various refiningprocesses such as h
21、ydrotreating, solvent extraction, and soforth. It has secondary application in relating the chemicalnature of an oil to other phenomena that have been demon-strated to be related to oil composition.FIG. 1 Correlation Chart for Determining % CA,%CN, and % CPD2140 08 (2017)25.2 Results obtained by thi
22、s practice are similar to, but notidentical with, results obtained from Test Method D3238. Therelationship between the two and the equations used in derivingFig. 1 are discussed in the literature.35.3 Although this practice tends to give consistent results, itmay not compare with direct measurement
23、test methods suchas Test Method D2007.6. Apparatus6.1 No specific apparatus is required. However, to obtain theVGC and riparameters of Fig. 1, certain measurements ofbasic physical properties of the test oil must be made. Theapparatus required for those measurements is as specified inASTM test metho
24、ds as detailed in Section 7.7. Procedure7.1 Obtain a uniform sample of the oil to be analyzed forcarbon-type composition, using sampling procedures as speci-fied in Practices D923.7.2 Determine the viscosity, density and relative density(specific gravity), and refractive index of the sample experi-m
25、entally by the procedures specified in the following testmethods:7.2.1 ViscositySee Test Method D445.7.2.2 Density and Relative Density (Specific Gravity)SeeTest Method D1481 or D4052.7.2.3 Refractive Index See Test Method D1218.8. Calculation8.1 From the measured viscosity and specific gravity prop
26、-erties of the oil sample (7.2) calculate the viscosity-gravityconstant, VGC, as follows (Note 3):VGC 5G10.0887 2 0.776 log log10V 2 4!1.082 2 0.72 log log10V 2 4!where:G = relative density (specific gravity) at 15.6C (60F), andV = viscosity, cSt at 37.8C (100F).NOTE 3This equation for VGC was devis
27、ed by Moore and Kaye.4Accurate VGC data may be obtained using other equations and othermeasurement temperatures. Test Method D2501 gives some of thesealternatives.8.2 From the measured density and refractive index proper-ties of the oil sample (7.2) calculate the refractivity intercept,ri, as follow
28、s:ri5 nD202 d/2!where:nD20= refractive index at 20C (68F) for D line of sodium,andd = density at 20C (68F).8.3 Enter the correlation chart, Fig. 1, with the values ofVGC and ri, from 8.1 and 8.2. Read from Fig. 1 the corre-sponding values of % CA,%CN, and % CP.8.4 For oils containing 0.8 % or more s
29、ulfur, the accuracy ofthis practice may be improved by applying a sulfur correction.This may be done by use of the following equations (Note 4):Sulfur correction for% CN52weight% S/0.288Sulfur correction for% CP51weight% S/0.216Sulfur correction for% CA5 100 2 corrected % CN1corrected % CP!NOTE 4Com
30、mercially available oils of the types to which this methodapplies normally have sulfur contents of less than 0.8 %. Therefore it isunlikely that a sulfur correction will be necessary. For new or experimen-tal oils, or whenever the true sulfur content is unknown, the determinationof that quantity is
31、recommended. A satisfactory method is described inTest Method D129.49. Report9.1 Report the following information:9.1.1 Designation of practice used (D2140),9.1.2 Sample identification.9.1.3 Percent of aromatic ring carbons (% CA).9.1.4 Percent of naphthenic ring carbons (% CN), and9.1.5 Percent of
32、paraffinic chain carbons (% CP).NOTE 5The total of 9.1.3, 9.1.4, and 9.1.5 should equal 100 %.10. Keywords10.1 carbon type; composition; electrical oils; mineral oils;oilsASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedi
33、n 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 committee and mu
34、st be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of th
35、eresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C70
36、0, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permissio
37、n rights to photocopy the standard may also be secured from the Copyright Clearance Center, 222Rosewood Drive, Danvers, MA 01923, Tel: (978) 646-2600; http:/ S. S., King, R. W., Stout, W. J., Partikian, D. G., and Skrabek, E. A.,“Relationship Between Carbon-Type Composition, Viscosity-Gravity Constant, andRefractivity Intercept of Viscous Fractions of Petroleum,” Analytical Chemistry,Vol28, 1956, pp 19281936.4Proc., 15th API Annual Meeting, November 1934, Section II, p. 7.D2140 08 (2017)3
