1、Designation:C21095(Reapproved 2014)Standard Test Method forReheat Change of Insulating Firebrick1This standard is issued under the fixed designation C210;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A num
2、ber in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S.Department of Defense.1.Scope1.1 This test method covers the determination of the perma-ne
3、nt linear(and volume)change of insulating firebrick uponreheating under prescribed conditions.1.2 The values stated in inch-pound units are to be regardedas the standard.The values given in parentheses are forinformation only.1.3This standard does not purport to address all of thesafety concerns,if
4、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:2C24 Test Method for Pyrometric Cone Equivalent(PCE)
5、ofFireclay and High Alumina Refractory MaterialsC155 Classification of Insulating FirebrickE230 Specification and Temperature-Electromotive Force(EMF)Tables for Standardized ThermocouplesE1256 Test Methods for Radiation Thermometers(SingleWaveband Type)3.Significance and Use3.1 Insulating firebrick(
6、IFB)are classified by their bulkdensity and reheat change(see Classification C155).This testmethod defines thermal stability by measurement of IFBsreheat change following 24 h at a test temperature.3.2 Since this test exposes the entire sample to an isothermaltemperature condition,the user should be
7、 aware that mostapplications for IFB involve a thermal gradient which maycause the IFBs dimensions to change differentially.4.Apparatus4.1 The test kiln shall be capable of maintaining therequired temperature with a variation of not more than one halfa standard pyrometric cone over the hearth area d
8、uring theprescribed heating schedule.If a gas-or oil-fired kiln is used,it shall be of the downdraft type and of such a design as not topermit the flame from the burner to impinge upon the testspecimens.The kiln atmosphere during the test shall be kept asoxidizing as is practicable.5.Procedure5.1 Te
9、st Specimens and Measurements:5.1.1 The test specimens shall consist of three brick(Note 1)measuring 9 by 412by 212or 3 in.(228 by 114 by 64 or 76mm)or three pieces of these dimensions cut out of largershapes.NOTE1Three supporting brick from the same lot as the test specimensare required also,so tha
10、t the test sample is comprised of six brick.5.1.2 Each specimen shall be labeled with ceramic paint,and before and after heating they shall be carefully measuredfor length(Note 2),width,and thickness.Three measurements(Note 3)to the nearest 0.02 in.(0.5 mm)shall be taken for eachdimension and the av
11、erage of these shall be used.Eachdimension shall be measured in three places along the longi-tudinal center line on opposite faces,one measurement at thecenter of the line and one12in.(13 mm)in from each edge.Fig.1 shows the location at which these measurements are tobe made.NOTE2For classifying IFB
12、 according to Classification C155,obtainthe reheat change from the 9-in.(228-mm)dimension measurements only.NOTE3Because of the large pore size of some IFB,it is difficult tomeasure by means of calipers directly on the brick surfaces.Accuracy maybe obtained by holding two small pieces of flat polish
13、ed steel plate ofknown thickness against the faces between which the dimension is to beobtained,and calipering on the outside steel surfaces rather than directlyagainst the brick surfaces.It is permissible to use a measuring device toobtain the dimensions of the brick,provided the measurements are n
14、otaffected by large pores in the surface.5.2 Placing Test Specimens in Kiln:5.2.1 Place the test specimens in the kiln so that each willrest on a 9 by 212or 3-in.(228 by 64 or 76-mm)face.Placeeach specimen upon the 9 by 212or 3-in.face of a supportingbrick that shall be from the same lot as the test
15、 specimen.Place1This 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 Sept.1,2014.Published November 2014.Originallyapproved in 1946.Last previous edition approved in 2007
16、 as C210 95(2007)1.Originally part of C93.DOI:10.1520/C0210-95R14.2For 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 Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 between the test specimen and the supporting member a layerof suitable refractory material
