1、Designation: C577 072Standard Test Method forPermeability of Refractories1This standard is issued under the fixed designation C577; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in parentheses
2、indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1NOTEUnits of measure statement was added editorially in March 2009.2NOTEFigure 1 was corrected editorially in November 2009.1. Scope1.1 This test method covers determin
3、ation of the permeabil-ity of refractory brick and monoliths, from which suitablespecimens can be cut, at room temperature.1.2 UnitsThe values stated in inch-pound units are to beregarded as standard. The values given in parentheses aremathematical conversions to SI units that are provided forinform
4、ation only and are not considered standard.1.2.1 ExceptionsThe apparatus used in this standard isonly available in SI units (Section 4). Also, some of thecalculations must use SI units only.1.3 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It i
5、s 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:2C1095 Practice for Calculating Precision Data on Refracto-ries (C08) from Interlab
6、oratory Test Results.33. Significance and Use3.1 This test method is used to measure the rate of flow ofair or nitrogen through refractory brick and monoliths and tothus determine the permeability of tested products.3.2 This test method is useful in research and developmentfor establishing the relat
7、ive permeability of products withincomparable classes. It may also be used to identify acceptableproducts for design purposes and to establish permeabilitycriteria for specification acceptance.3.3 It must be recognized that permeability can vary indifferent directions and different parts of a refrac
8、tory due tofactors such as forming procedure, grain size and distribution,and heat treatment.4. Apparatus4.1 The apparatus shall provide a leakproof system fortesting 2 in. (51 mm) cubes held in a pressurized rubber gasket,with means for controlling gas pressure and measuring gasflow. Figs. 1-3 illu
9、strate a suitable apparatus.4The apparatusconsists of the following components:4.1.1 Permeating Medium, air or nitrogen with regulator-controlled inlet pressure.4.1.2 Drier Tubes, each filled with a desiccant and strainer;used to remove any water or dirt from the gas before enteringthe flowmeters.4.
10、1.3 FlowmetersThey will measure the flow of permeat-ing media in the range from 0 to 9000 cm3/min. Theflowmeters may be calibrated to read the flow directly of eitherair or nitrogen. The range for each flowmeter is shown in Fig.1.4.1.4 ManometerAmultiple scale digital manometer shallbe used to measu
11、re the differential pressure across the speci-men.4.1.5 Rubber Specimen-Sealing GasketThe gasket (Fig.2) is made to fit tightly arounda2by2by2in.(51by51by51 mm) test specimen. The two tapered metal-gasket holders(Fig. 3) enclose the rubber gasket, and are compressed with ahydraulic jack (Fig. 4) to
12、seal the gasket tightly against the testspecimen.5. Specimen Preparation5.1 One 2 by 2 by 2 in. (51 by 51 by 51 mm) specimen shallbe cut from each of four pieces constituting the sample ofmaterial to be tested. The specimen should be cut in such amanner as to fit snugly into the gasket.5.2 The speci
13、mens shall be cut so that three originalsurfaces are retained. In cases where it is desirable to determine1This test method is under the jurisdiction of ASTM Committee C08 onRefractories and is the direct responsibility of Subcommittee C08.03 on PhysicalProperties.Current edition approved June 1, 20
14、07. Published July 2007. Originally approvedin 1965. Last previous edition approved in 1999 as C577 99. DOI: 10.1520/C0577-07E01.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume informati
15、on, refer to the standards Document Summary page onthe ASTM website.3C084The apparatus is described in Eusner , G. R., and Shapland, J. T., “Permeabilityof Blast-Furnace Refractories,” Journal ,Am. Ceramic Soc., Vol. 42, No. 10, 1959,pp. 459464.1Copyright ASTM International, 100 Barr Harbor Drive, P
16、O Box C700, West Conshohocken, PA 19428-2959, United States.the permeability of specimens that show directional differencesin permeability, the original surfaces shall be identified, and thevalues determined separately for each direction of gas flow.5.3 The specimens shall be dried for 16 h at 220 t
17、o 230F(105 to 110C) and cooled to room temperature before testing.After drying, all specimen surfaces shall be blown free of dustwith clean dry air and tested within 4 h.6. Procedure6.1 Check the system for leaks. This may be accomplishedby taking readings with an impermeable material in thespecimen
18、 holder or by utilizing flowmeters in the line ahead ofthe test specimen.FIG. 1 Permeability ApparatusC577 07226.2 Place the specimen in the rubber gasket, and enclose itbetween the two halves of the gasket holder. Force the halvesof the gasket holder together to seal the specimen in the gasket.FIG.
19、 1 Permeability Apparatus (continued)SI Equivalentsin. 1 15/16 2 4mm 49 51 102FIG. 2 Rubber Specimen-Sealing GasketSI Equivalentsin.14 212 4mm 6 64 102FIG. 3 Tapered Stainless Steel Gasket HolderC577 07236.3 Pass dried air (or nitrogen) through the specimen toproduce a differential pressure across t
20、he specimen of 240 mmHg (32.0 kPa) and measure the rate of air (or nitrogen) flow.Measure the differential pressure with the mercury manometerand the rate of air flow with a flowmeter, which will indicate anear full-scale reading on the low-pressure side of the speci-men.6.4 Also measure the rate of
21、 air (or nitrogen) flow fordifferential pressures of 140 and 70 mm Hg (18.7 and 9.3 kPa)if the rate of air flow does not exceed 9000 cm3/min when thedifferential pressure across the specimen is 240 mm Hg.6.5 If the air (or nitrogen) flow exceeds 9000 cm3/min whenthe differential pressure across the
22、specimen is 240 mm Hg,measure the rate of flow at differential pressures of 240, 140,and 70 mm (2.3, 1.4, and 0.7 kPa) of water.6.6 On specimens where directional permeability is to bedetermined, test the two remaining specimen orientations.7. Calculation7.1 When using air, calculate the permeabilit
23、y in centidar-cys (Note) at room temperature, using one of the formulasbelow which depend on the type of manometer used. Ifnitrogen is used as the permeating medium, the permeability ascalculated by either of the formulas should be decreased by5 %, since the viscosity of nitrogen at room temperature
24、 isapproximately 5 % lower than that of air.NOTE 1One centidarcy is a flow of 0.01 cm3/s of a fluid of 1 cPviscosity through a 1-cm cube under a pressure difference of 1 atm. Toconvert to flow in in.3/sin.2of areain. of thicknesspsi pressure difference,divide by 174.K 5 0.451 3 F!/DPm1 1 DPm/152!# (
25、1)orK 5 6.19 3 F!/DPw(2)where:F = flow, cm3/min,DPm= differential pressure, cm Hg,DPw= differential pressure, cm of water, andK = permeability, centidarcys.7.2 These equations were derived from the following gen-eral relation with the viscosity of the permeating gas (air) takenas 182.7 P.K 5 MQL/ADP
26、! 3 100 (3)SI Equivalentsin. mm in. mm12151325127816203406FIG. 4 Hydraulic-Jack AssemblageC577 0724where:K = permeability, centidarcys,M = gas viscosity, cP,Q = flow rate, cm3/s,Q = sample length, cm,A = sample area, cm2, andDP = absolute pressure drop across the sample, atm.8. Report8.1 The permeab
27、ility shall be reported as the average of thefour specimens. Where information is required on directionalpermeability, the average of the four specimens shall bereported individually for each of the three specimen orienta-tions.9. Precision and Bias59.1 Interlaboratory DataAn interlaboratory round r
28、obinwas conducted in which seven laboratories each tested fourspecimens from two different types of refractory materials.Results were published in 1993 Research Report No. 1378.Each laboratory performed two trials on each specimen todetermine the permeability in centidarcys. The components ofvarianc
29、e from this study expressed as standard deviation andrelative standard deviation are given in Table 1. Refer toPractice C1095 for calculating precision data on refractoriesfrom interlaboratory test results.9.2 Precision:9.2.1 RepeatabilityThe maximum permissible differencedue to test error between t
30、wo test results obtained by oneoperator on the same material using the same test equipment isgiven by the repeatability interval and the relative repeatabilityinterval (coefficient of variation). The 95 % repeatability inter-vals are given in Table 1. Two test results which do not differby more than
31、 the repeatability interval will be considered to befrom the same population; and, conversely, two test resultswhich do differ by more than the repeatability interval will beconsidered to be from different populations.9.2.2 ReproducibilityThe maximum permissible differ-ence due to test error between
32、 two test results obtained by twooperators in different laboratories on the same material usingthe same test equipment is given by the reproducibility intervaland the relative reproducibility interval (coefficient of varia-tion). The 95 % reproducibility intervals are given in Table 1.Two test resul
33、ts which do not differ by more than thereproducibility interval will be considered to be from the samepopulation; and, conversely, two test results which do differ bymore than the reproducibility interval will be considered to befrom different populations.9.3 BiasNo justifiable statement on bias is
34、possible sincethe true physical property values of refractories cannot beestablished by an acceptable reference material.10. Keywords10.1 centidarcy; gas flow; permeability; refractoriesASTM International takes no position respecting the validity of any patent rights asserted in connection with any
35、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 c
36、ommittee and must 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
37、a meeting of theresponsible 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 Dr
38、ive, PO Box C700, 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.
39、org). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).5Supporting data are available from ASTM Headquarters. RequestRR:C 81378.TABLE 1 Precision StatisticsBrick Type Average, xStandard Deviation Precision Coefficient of Variation RelativeRepeatability% rRelativeReproducibility% RWithinSrBetweenSRRepeatabilityInterval, rReproducibilityInterval, RWithin LabVrBetween Labs VRSuper dutyfirebrick25.07 1.38 3.27 3.86 9.16 5.65 12.82 15.81 35.8880 % alumina 11.17 0.16 1.84 0.44 5.14 1.67 16.98 4.68 47.55C577 0725
