1、Designation: C 24 01 (Reapproved 2006)Standard Test Method forPyrometric Cone Equivalent (PCE) of Fireclay and HighAlumina Refractory Materials1This standard is issued under the fixed designation C 24; the number immediately following the designation indicates the year of originaladoption or, in the
2、 case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A superscriptepsilon (e) indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1. Scope1.1 This
3、test method covers the determination of the Pyro-metric Cone Equivalent (PCE) of fire clay, fireclay brick, highalumina brick, and silica fire clay refractory mortar by com-parison of test cones with standard pyrometric cones under theconditions prescribed in this test method.1.2 The values stated i
4、n inch-pound units are to be regardedas standard. The values given in parentheses are for informa-tion only.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
5、and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2C71 Terminology Relating to RefractoriesE11 Specification for Wire Cloth and Sieves for TestingPurposesE 220 Test Method for Calibration of Thermocouples ByComparis
6、on TechniquesE 691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method3. Terminology3.1 DefinitionsFor definitions of terms used in this testmethod, see Terminology C71.4. Summary of Test Method4.1 This test method consists of preparing a test cone froma refra
7、ctory material and comparing its deformation end pointto that of a standard pyrometric cone. The resultant PCE valueis a measure of the refractoriness of the material.4.2 Temperature equivalent tables for the standard coneshave been determined by the National Institute of Standardsand Technology whe
8、n subjected to both slow and rapid heatingrates.5. Significance and Use5.1 The deformation and end point of a cone corresponds toa certain heat-work condition due to the effects of time,temperature, and atmosphere.5.2 The precision of this test method is subject to manyvariables that are difficult t
9、o control. Therefore, an experiencedoperator may be necessary where PCE values are being utilizedfor specification purposes.5.3 PCE values are used to classify fireclay and highalumina refractories.5.4 This is an effective method of identifying fireclayvariations, mining control, and developing raw
10、material speci-fications.5.5 Although not recommended, this test method is some-times applied to materials other than fireclay and high alumina.Such practice should be limited to in-house laboratories andnever be used for specification purposes.6. Procedure6.1 Preparation of Sample:6.1.1 Clay or Bri
11、ckCrush the entire sample of fire clay orfireclay brick, in case the amount is small, by means of rolls ora jaw crusher to produce a particle size not larger than14 in. (6mm). If the amount is large, treat a representative sampleobtained by approved methods. Then mix the sample thor-oughly and reduc
12、e the amount to about 250 g (0.5 lb) byquartering (see Note 1). Then grind this portion in an agate,1This test method is under the jurisdiction of ASTM Committee C08 onRefractories and is the direct responsibility of Subcommittee C08.02 on ThermalProperties.Current edition approved March 1, 2006. Pu
13、blished March 2006. Originallyapproved in 1919. Last previous edition approved in 2001 as C 24 01.2For 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 Docu
14、ment Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.porcelain, or hard steel mortar and reduce the amount again byquartering. The final size of the sample shall be 50 g and thefineness capable of pass
15、ing an ASTM No. 70 (212-m) sieve3(equivalent to a 65-mesh Tyler Standard Series). In order toavoid excessive reduction to fines, remove them frequentlyduring the process of reduction by throwing the sample on thesieve and continuing the grinding of the coarser particles untilall the sample passes th
16、rough the sieve (see Note 2). Takeprecautions to prevent contamination of the sample by steelparticles from the sampling equipment during crushing orgrinding.NOTE 1Take care during the crushing and grinding of the sample toprevent the introduction of magnetic material.NOTE 2The requirement to grind
17、the coarser particles is particularlyimportant for highly siliceous products; excessively fine grinding mayreduce their PCE by as much as two cones.6.1.2 Silica Fire Clay (see 3.1)In the case of silica fireclay, test the sample obtained by approved methods as receivedwithout grinding or other treatm
18、ent.6.2 Preparation of Test Cones:6.2.1 After preparing samples of unfired clays (Note 3), orof mixes containing appreciable proportions of raw clay, inaccordance with 6.1.1, heat them in an oxidizing atmosphere inthe temperature range from 1700 to 1800F (925 to 980C) fornot less than 30 min.NOTE 3S
19、ome unfired clays bloat when they are formed into cones andare carried through the high-temperature heat treatment prescribed in 5.4.1without preliminary calcining. The substances that cause bloating can, inmost cases, be expelled by heating the clay samples before testing.6.2.2 The clay sample may
20、be given the heat treatmentprescribed in 6.2.1 after it has been formed into a cone (see6.2.3), but this procedure has been found not as effective as thetreatment of the powdered material. If cones so prepared bloatduring the PCE test, heat a portion of the original sample in itspowdered condition a
21、s prescribed in 6.2.1 and then retest it.6.2.3 Thoroughly mix the dried sample, and after theaddition of sufficient dextrine, glue, gum tragacanth, or otheralkali-free organic binder and water, form it in a metal moldinto test cones in the shape of a truncated trigonal pyramid withits base at a smal
22、l angle to the trigonal axis, and in accordancewith dimensions shown in Fig. 1. In forming the test cone usethe mold shown in Fig. 2.6.3 Mounting:6.3.1 Mount both the test cones and the Standard Pyromet-ric Cones on plaques of refractory material that have acomposition that will not affect the fusib
23、ility of the cones (seeNote 4). Mount both test and PCE cones with the baseembedded so that the length of the sloping face of the coneabove the plaque shall be1516 in. (24 mm) and the face of thecone (about which bending takes place) shall be inclined at anangle of 82 with the horizontal. Arrange th
24、e test cones withrespect to the PCE cones as shown in Fig. 3, that is, alternatethe test cones with the PCE cones in so far as is practical (seeNote 5). The plaque may be any convenient size and shape andmay be biscuited before using, if desired.NOTE 4A satisfactory cone plaque mix consists of 85 %
25、fusedalumina and 15 % plastic refractory clay. For tests that will not go aboveCone 34, the plastic refractory clay may be increased to 25 % and thealumina may be replaced with brick grog containing over 70 % alumina.The alumina or grog should be ground to pass an ASTM No. 60 (250-m)sieve (equivalen
26、t to a 60-mesh Tyler Standard Series), and the PCE of therefractory plastic clay should be not lower than Cone 32.NOTE 5The number of cones and their mounting facing inward asshown in Fig. 3 is typical for gas-fired furnaces of relatively largedimensions and gases moving at high velocity. The practi
27、cal bore of themuffle tubes in most electric furnaces does not permit cone pats of thissize. The static atmosphere prevailing permits the cones being mounted toface outward, if so desired.6.4 Heating:6.4.1 Perform the heating in a suitable furnace, operatingwith an oxidizing atmosphere, at rates to
28、conform to thefollowing requirements (see Note 6 and Note 7). It is advisable,but not mandatory that the furnace temperature be controlledwith a calibrated4thermocouple or radiation pyrometer con-nected to a program-controlled recorder.6.4.1.1 For PCE tests expected to have an end point of PCECone 1
29、2 or above, but not exceeding Cone 26, heat at the rateprescribed in Table 1.3Detailed requirements for this sieve are given in Specification E11.4Test Method E 220 specifies calibration procedures for thermocouples.NOTE 1Dimensions are in inches.SI Equivalentsin. mm0.075 1.900.272 6.910.281 7.141.0
30、81 27.461.125 28.58FIG. 1 Standard Pyrometric Test ConeC 24 01 (2006)26.4.1.2 For PCE tests expected to have an end point aboveCone 26, heat at the rate prescribed in Table 2.NOTE 6The heating rate through the cone series in both Table 1 and2 is at 270F (150C)/h.NOTE 7Following a test run, the cone
31、pat may be removed at 1830F(1000C) and a new pat may be put in without cooling the furnace tobelow red heat. The time interval to bring the furnace, using Table 1,upto Cone 12 shall be not less than 20 min, and using Table 2, the timeinterval up to Cone 20 shall be not less than 25 min.6.4.2 The fur
32、nace atmosphere shall contain a minimum of0.5 % oxygen with 0 % combustibles. Make provisions toprevent any external forces from being exerted on the cones orcone plaque, such as from flames or gases. Test the furnace atintervals to determine the uniformity of the distribution of theheat.6.5 Pyromet
33、ric Cone Equivalent:6.5.1 The softening of the cone will be indicated by the topbending over and the tip touching the plaque.Always report thebloating, squatting, or unequal fusion of small constituentparticles. Report the Pyrometric Cone Equivalent (PCE) interms of Standard Pyrometric Cones and the
34、 cone that mostnearly corresponds in time of softening with the test cone. Ifthe test cone softens later than one Standard Pyrometric Conebut earlier than the next Standard Pyrometric Cone andapproximately midway between, report the PCE as Cone3334.6.5.2 If the test cone starts bending at an early c
35、one but isnot down until a later cone, report this fact.6.5.3 The temperatures corresponding to the end points ofthe Standard Pyrometric Cones are frequently of interest andare shown in Appendix X1.7. Precision and Bias7.1 Precision and bias are based on four participatinglaboratories. Although six
36、labs are preferred, further participa-tion is not anticipated or perceived possible.7.2 Interlaboratory DataAn interlaboratory round robinwas conducted in which four laboratories each tested speci-mens from four different types of refractory materials.5Eachlaboratory performed three trials on each s
37、ample to determinethe pyrometric cone equivalent (PCE). The cone differences are5Supporting data are available from ASTM Headquarters. Request RR:C081018.Table of Dimensionsin. mm in. mmA 0.50 12.7 K 2.500 63.50B 0.75 19.0 L 2.75 69.8C 2.510 63.75 M 1.00 25.4D 1.084 27.53 N 0.12 3.0E 1.015 25.78 O 0
38、.62 15.7F 0.229 5.82 P 0.75 19.0G 0.75 19.0 Q 0.75 19.0H 0.460 11.68 R 1.50 38.1I 0.399 10.13 S 0.75 19.0J 0.75 19.0 T 2.62 66.5FIG. 2 Split Mold for ASTM Pyrometric Test ConeFIG. 3 Method of Mounting Test Cones and Appearance AfterTestingTABLE 1 Heating Rates Up to Cone 26Cold Test Furnaceto Cone N
39、o.Time inter-val, minCumulativeTime, h:min12 45 0:4513 5 0:5014 19 1:0915 13 1:2216 24 1:4617 9 1:5518 4 1:5919 8 2:0720 9 2:1623 16 2:3226 7 2:39C 24 01 (2006)3adjacent cones, not numeric cones. The components of vari-ance from this study expressed as standard deviation andrelative deviation are gi
40、ven in Table 3. Refer to Practice E 691for calculation of the components of variance.7.3 PrecisionRepeatability and reproducibility statisticswere calculated at the 95% confidence level. The relativerepeatability statistic means that two test results of PCEobtained in one laboratory should not vary
41、by more than about1.47% for silica brick, for example. The relative reproducibil-ity statistic means that two laboratories each obtaining a testresult of PCE of silica brick should not differ by more thanabout 4.86 %, for example.7.4 BiasNo justifiable statement on bias is possible sincethe true phy
42、sical property values of refractories cannot beestablished by an acceptable reference material.8. Keywords8.1 PCE; pyrometric cone; pyrometric cone equivalent;refractoriesTABLE 2 Heating Rates Above Cone 26Cold Test Furnaceto Cone No.Time Inter-val, minCumulativeTime, h:min20 45 0:4523 16 1:0126 7 1
43、:0827 7 1:1528 3 1:1829 5 1:2330 3 1:2631 7 1:333112 6 1:3932 7 1:463212 3 1:4933 7 1:5634 9 2:0535 9 2:1436 7 2:2137 7 2:28C 24 01 (2006)4APPENDIX(Nonmandatory Information)X1. TEMPERATURES CORRESPONDING TO STANDARD PYROMETRIC CONE END POINTSX1.1 The approximate temperature equivalents correspond-in
44、g to the end points of those Standard Pyrometric Cones thatare used in connection with refractory testing are as shown inTable X1.1.X1.2 Heating Rate:X1.2.1 Cones 12 to 37, inclusive270F (150C)/h.X1.2.2 Cone 38180F (100C)/h.X1.2.3 Cones 39 to 42, inclusive1080F (600C)/h.X1.3 Standard Pyrometric Cone
45、s 28 and 30 are manufac-tured but are not used in the PCE test.X1.4 Temperatures for Cones 12 to 37 were reported at theNational Institute of Standards and Technology.6Temperaturesfor Cones 38 to 42 were determined by C. O. Fairchild and M.F. Peters.7These temperatures apply satisfactorily for all t
46、heconditions of this test method, but do not apply to theconditions of commercial firing of kilns and use of refractorymaterials.X1.5 Temperature values were determined in degreesCelsius; Fahrenheit temperature values were calculated.6Beerman, H. P., Journal of the American Ceramic Society , Vol 39,
47、 No. 2H,1956, pp. 4753.7Fairchild, C. O., and Peters, M. F., “Characteristics of Pyrometric Cones,”Journal of the American Ceramic Society, Vol 9, No. 11, November 1976, p. 700.TABLE 3 Repeatability and Reproducibility DataBrick Type Average, x Standard Deviation Precision Coeffecient of VariationRe
48、lativeRepeatability%rRelativeReproducibility%RWithin Sr BetweenSRRepeatabilityInterval, rReproducibilityInterval, RWithin LabVrBetween LabsVRSilica Brick 30.75 0.16 0.53 0.45 1.50 1.47 4.86Low Duty Firebrick 15.71 0.14 0.28 0.40 0.77 2.57 4.93High Duty Firebrick 32.15 0.22 0.33 0.61 0.92 1.89 2.85Cl
49、ay 27.42 0.60 0.80 1.67 2.23 6.07 8.14TABLE X1.1 Temperature Equivalents for Pyrometric ConesUsed in Refractory TestingCone No. End Point, F (C) Cone No. End Point, F (C)12 2439 (1337) 31 3061 (1683)13 2460 (1349) 3112 3090 (1699)14 2548 (1398) 32 3123 (1717)15 2606 (1430) 3212 3135 (1724)16 2716 (1491) 33 3169 (1743)17 2754 (1512) 34 3205 (1763)18 2772 (1522) 35 3245 (1785)19 2806 (1541) 36 3279 (1804)20 2847 (1564) 37 3308 (1820)23 2921 (1605) 38 3335 (1835)26 2950 (1621) 39 3389 (1865)27 2984 (1640) 40 3425 (1885)28 2995 (1646) 41 3
