1、Designation: C 201 93 (Reapproved 2004)Standard Test Method forThermal Conductivity of Refractories1This standard is issued under the fixed designation C 201; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revisio
2、n. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers the determination of the com-parative thermal conductivity of refractories under standard-ized conditions
3、 of testing. This test method is designed forrefractories having a conductivity factor of not more than 200Btuin./hft2F (2818 W/mK), for a thickness of 1 in. (25 mm).1.2 Detailed ASTM test methods to be used in conjunctionwith this procedure in testing specific types of refractorymaterials are as fo
4、llows: Test Method C 182, Test MethodC 202, Test Method C 417, and Test Method C 767.1.3 The values stated in inch-pound units are to be regardedas the standard. The values in parentheses are provided forinformation only.1.4 This standard does not purport to address all of thesafety concerns, if any
5、, 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:2C 134 Test Methods for Size, Dimensional Measuremen
6、ts,and Bulk Density of Refractory Brick and InsulatingFirebrickC 155 Classification of Insulating FirebrickC 182 Test Method for Thermal Conductivity of InsulatingFirebrickC 202 Test Method for Thermal Conductivity of RefractoryBrickC 417 Test Method for Thermal Conductivity of UnfiredMonolithic Ref
7、ractoriesC 767 Test Method for Thermal Conductivity of CarbonRefractoriesE 220 Method for Calibration of Thermocouples by Com-parison Techniques3. Significance and Use3.1 The thermal conductivity of refractories is a propertyrequired for selecting their thermal transmission characteris-tics. Users s
8、elect refractories to provide specified conditions ofheat loss and cold face temperature, without exceeding thetemperature limitation of the refractory. This test methodestablishes the testing for thermal conductivity of refractoriesusing the calorimeter.3.2 This procedure requires a large thermal g
9、radient andsteady state conditions. The results are based upon a meantemperature.3.3 The data from this test method are suitable for specifi-cation acceptance, and design of multi-layer refractory con-struction.3.4 The use of these data requires consideration of the actualapplication environment and
10、 conditions.4. Apparatus4.1 The apparatus shall conform in close detail with thatshown in the approved drawings.3The equipment is shown inFig. 1 and Fig. 2, and the essential parts are as follows:4.1.1 Heating ChamberA heating chamber, shown in Fig.3, shall be capable of being heated electrically ov
11、er a tempera-ture range from 400 to 2800F (205 to 1540C) in a neutral oroxidizing atmosphere. The temperature of the heating unit shallbe controlled by a mechanism capable of maintaining thetemperature in the chamber constant to within 65F (63C). Asilicon carbide slab 1312 by 9 by 1 in. (342 by 228
12、by 25 mm),with the 1312 by 9-in. (342 by 228 mm) faces plane andparallel, shall be placed above the sample for the purpose ofproviding uniform heat distribution. A layer of insulationequivalent at least to 1 in. (25 mm) of Group 20 insulatingfirebrick (see Classification C 155) shall be placed below
13、 thecalorimeter and guard plates.4.1.2 Calorimeter AssemblyA copper calorimeter assem-bly, of the design shown in Fig. 4, shall be used for measuringthe quantity of heat flowing through the test specimen. The1This test method is under the jurisdiction of ASTM Committee C08 onRefractories and is the
14、direct responsibility of Subcommittee C08.02 on ThermalStress Resistance.Current edition approved Sept. 1, 2004. Published October 2004. Originallyapproved in 1945. Last previous edition approved in 1998 as C 201 93 (1998).2For referenced ASTM standards, visit the ASTM website, www.astm.org, orconta
15、ct ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3The complete set of approved drawings necessary for the construction of theapparatus and suggested operating instructions, each of which
16、requires too muchspace to be included with this test method, were originally drafted by the InsulatingProducts Division of Babcock and Wilcox Co. ASTM has been advised that thesedrawings are no longer available. Subcommittee C08 .05 currently is taking thisissue under advisement.1Copyright ASTM Inte
17、rnational, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.water circulation is such that adjacent passages contain incom-ing and outgoing streams of water. The calorimeter shall be 3by 3 in. (76 by 76 mm) square and shall have one inlet and oneoutlet water connec
18、tion. The inner guard surrounding thecalorimeter shall be 1312 by 9 in. (342 by 228 mm) and shallhave two inlet and two outlet water connections. The outerguard shall extend 2 in. (51 mm) laterally from the inner guardand shall extend vertically to the member comprising thebottom of the heating cham
19、ber (see Fig. 3). The separationbetween the calorimeter and the inner guard shall be132 in. (0.8mm).4.1.3 Water-Circulating SystemA water-circulating sys-tem shall be provided for supplying the calorimeter assemblywith water at constant pressure and at a temperature that is notchanging at a rate gre
20、ater than 1F (0.5C)/h. The inlet waterpressure shall be at least the equivalent of 10 ft of hydrostaticpressure (29.9 kPa). The inlet water temperature shall at alltimes be within +5F (+3C) or 2F (1C) of the roomtemperature. Fig. 5 shows the arrangement that shall be usedfor meeting these conditions
21、. The regulating valves for con-trolling the rate of water flow through the calorimeter assemblyshall be capable of maintaining a constant rate of flow within61 % during the test period.4.1.4 Instruments for Measuring Temperature ofSpecimenCalibrated4thermocouples shall be embedded inthe test specim
22、en for measuring the temperature. Theelectromo-tive force (emf) for the temperature readings shallbe taken with a potentiometer having an instrument error of notmore than 60.05 mV, and the cold junctions of the thermo-couples shall be immersed in a mixture of ice and water.4.1.5 Instrument for Measu
23、ring Temperature Rise in Calo-rimeter WaterA multiple differential thermocouple shall beused for measuring5within an accuracy of not less than 1 % ofthe temperature rise of the water flowing through the calorim-eter. The thermocouple shall be immersed at least 312 in. (89mm) in the inlet and outlet
24、connections, and the junctions shallbe not more than14 in. (6 mm) distant from the bottom of thecalorimeter. A calibrated differential 10X copper-constantanthermocouple shall be used, and the millivolt readings shall betaken with a potentiometer having an instrument error of notmore than 60.01 mV in
25、 the range between 0 and 2 mV.4.1.6 Instruments for Measuring Temperature DifferenceBetween Calorimeter and Inner GuardCalibrated differential10X copper-constantan thermocouples shall be located in thecalorimeter and inner guard for measuring5the temperaturedifferences between the calorimeter and in
26、ner guard. Thetemperature difference during a test shall be maintained at avalue less than 60.05F (60.03C). The thermocouple junc-tions shall be placed in the four wells provided for thatpurpose, and millivolt readings shall be taken with a potenti-ometer having an instrument error of not more than
27、60.01 mVin the range between 0 and 2 mV.5. Test Sample and Its Preparation5.1 Test SampleThe test sample shall consist of three 9-in.(228-mm) straight brick and six 9 by 212 by 214-in. (228 by 64by 57-mm) soap brick (Note 2) that are representative of thematerial being tested. These brick shall be s
28、elected for unifor-mity of structure and bulk density, and they shall be free ofbroken corners or edges. One brick shall be used as the testspecimen, and one each of the other two brick shall be used asguard brick on either side of the specimen. The six soap brickshall be placed around the edges of
29、the test specimen and guardbrick to prevent side flow of heat. The test specimen and guardbrick shall cover an area of approximately 18 by 1312 in. (456by 342 mm).NOTE 1A total of nine 9-in. (228-mm) straight brick may be submit-ted for test, six of which would be cut to obtain the soap brick.5.2 Pr
30、eparation of Test SampleThe9by412-in. (228 by114-mm) faces of the three straight brick and the 9 by 214-in.(228 by 57-mm) faces of the soap brick shall be ground flat andparallel, and the thickness shall not vary more than 60.01 in.(60.3 mm). The thickness shall be not more than 3 (76 mm)nor less th
31、an 2 in. (51 mm). The sides that are to be placed in4Method E 220 specifies calibration procedures for thermocouples.5The following procedures are recommended: Roeser, W. F., “ThermoelectricThermometry,” and Roeser, W. F., and Wensel, H. T., “Methods of TestingThermocouples and Thermocouple Material
32、s,” Temperature, Its Measurement andControl, Reinhold Publishing Corp., New York, NY, 1941, pp. 180 and 284,respectively.NOTE 1The upper half of the heating chamber has been raised topermit introduction of the test samples.FIG. 1 Photograph of Thermal Conductivity ApparatusC 201 93 (2004)2contact sh
33、all be ground flat and at right angles to the 9 by412-in. face of the brick and the 9 by 214-in. face of the soapbrick.NOTE 2Additional instructions are given in the methods of test forspecific materials (see Section 7) concerning the preparation of thespecimen, placing of guard brick, and the like.
34、6. Bulk Density of Test Specimen6.1 The test specimen shall be dried at 220 to 230F (105 to110C) for 12 h, after which time its bulk density, in poundsper cubic foot (or kilograms per cubic metre) shall be deter-mined in accordance with Test Methods C 134, with theexception that the thickness measur
35、ement shall be made inaccordance with those methods.7. Procedure7.1 Use the procedures for testing specific types of refrac-tory materials as described in the following test methods: TestMethod C 182, Test Method C 202, Test Method C 417, andTest Method C 767.AConstant-head water supply. JMicroregul
36、ating valves.BInlet manifold and thermometer. LWater-level valve.CCirculating pump. MMagnetic control valve.DTo drain. NOutlet manifold.ECooling coil. OOverflow pipe.FWater filter. TThermostat (controls M).GCenter calorimeter. VValves.HInner guard calorimeter. WWater inlet.IOuter guard calorimeter.F
37、IG. 2 Diagram Showing Essential Parts of Thermal Conductivity ApparatusC 201 93 (2004)38. Record of Test Data8.1 Record the following data, and record 8.1.3 to 8.1.7 foreach 2-h test period (steady state of heat flow):8.1.1 Linear dimensions of test specimen,8.1.2 Distance between thermocouple junct
38、ions located inthe test specimen,8.1.3 Three sets of temperature readings as measured by thethermocouples in the test specimen,NOTE 1When testing insulating firebrick, the back-up insulation is removed.FIG. 3 Diagrammatic Section Through Heating ChamberFIG. 4 Design of Calorimeter and Guard RingsC 2
39、01 93 (2004)48.1.4 Mean temperature between each pair of thermo-couples in the test specimen as calculated from the tempera-tures recorded in 8.1.3,8.1.5 Average rise in temperature of the water flowingthrough the calorimeter,8.1.6 Average rate of water flow through the calorimeter,and8.1.7 Rate of
40、heat flow through the test specimen per unitarea.9. Calculation9.1 Calculate the thermal conductivity as follows:k 5 qL /A t12 t2!#where:k = thermal conductivity, Btuin./hft2F (or W/mK),q = Btu/h flowing into the calorimeter (temperature rise, F(K) of the water flowing through the calorimeter timest
41、he weight of flowing water, lb/h (or W),L = thickness (distance between hot junctions at which t1and t2are measured), in. (or m),t1= higher of two temperatures measured in the testspecimen, F (or K),t2= lower of two temperatures measured in the test speci-men, F (or K), andA = area of center calorim
42、eter, ft2(or m2).10. Report10.1 The report shall include the following:10.1.1 Brand name or other identifying information,10.1.2 Bulk density of the dried test specimen (see Section6),10.1.3 General description of the test specimen before andafter test with respect to possible structural changes cau
43、sed byexposing the test specimen to the heating chamber tempera-tures.10.1.4 The thermal conductivity data as calculated in accor-dance with Section 8 at the mean temperatures recorded duringa 2-h holding period with a steady state of heat flow, andreported at the mean of the two temperatures used i
44、n thecalculation.10.1.5 A curve showing the actual thermal conductivityvalues obtained versus mean temperatures, and10.1.6 When requested, the data recorded for Section 8 shallbe included in the report.11. Precision and Bias11.1 Interlaboratory Test Data:11.1.1 Results of round-robin tests between f
45、our laborato-ries on three varieties of refractory material ranging in k-valuefrom 2 to 165 were evaluated.11.1.2 Polynomial regressions were established by com-puter, and the residual sum of squares and degree of freedomwere summated for the within-laboratory variances. Between-laboratory variances
46、 were calculated from the regressioncurves of the four laboratories at four mean temperatures(500F, 1000F, 1500F, and 2000F).11.1.3 The components of variance for the thermal conduc-tivity, k, (Btuin./hft2F) expressed as coefficients of varia-tions were:Within laboratories, Vw= 3.4 %Between laborato
47、ries, Vb= 9.0 %11.2 PrecisionFor the components of variation given in11.1, two averages of test values will be considered signifi-cantly different at the 95 % probability level if the differenceequals or exceeds the critical differences listed as follows: (t =1.96)No. of Samples in EachAverageCritic
48、al differences, % of grand average k (Btuin./hft2F)(n)within-labprecisionbetween-labprecision, %1 9.4 % 26.62 6.6 % 25.83 5.5 % 25.55 4.2 % 25.011.3 Supplemental Interlaboratory Data One refractorymaterial was tested by four laboratories in which the thermo-couples were permanently affixed by one la
49、boratory. Polyno-mial regression equations on these data revealed the followingcomponents of variance:CCirculating pump. LWater-level valve.DTo drain. MMagnetic control valve.ECooling coil. OOverflow pipe.FWater filter. TThermostat (controls M).GCenter calorimeter. VValves.HInner guard calorimeter. WWater inlet.IOuter guard calorimeter.FIG. 5 Water-Circulating System with Automatic TemperatureControlC 201 93 (2004)5Within laboratories, Vw= 3.1 %Between laboratories, Vb= 2.3 %12
