ASTM_C_1446_-_11.pdf

Designation:C144611Standard Test Method forMeasuring Consistency of Self-Flowing CastableRefractories1This standard is issued under the fixed designation C1446;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 indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method covers the determination of the con-sistency(degree of self-flow)and working time of self-flowingcastable refractories.This test may optionally be used todetermine working time of self-flowing castables.1.2 The values stated in inch-pound units are to be regardedas the standard.The values given in parentheses are forinformation 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 and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2C71 Terminology Relating to RefractoriesC230/C230M Specification for Flow Table for Use in Testsof Hydraulic CementC860 Test Method for Determining the Consistency ofRefractory Castable Using the Ball-In-Hand TestC862 Practice for Preparing Refractory Concrete Specimensby CastingC1445 Test Method for Measuring Consistency of CastableRefractory Using a Flow TableE177 Practice for Use of the Terms Precision and Bias inASTM Test MethodsE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method3.Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 consistency of self-flowing castable refractoriesthedegree of mobility(self-flow)of the refractory castable underits own weight as described in this test method at the specifiedtimes after adding liquid to the mixer.3.1.2 working time of self-flowing castable refractoriestheelapsed time from the first addition of liquid during mixinguntil the mix will only achieve 25%self-flow using theprocedure described in this test method.4.Summary of Test Method4.1 The castable refractory is mixed with a tempering liquidand the percentage of self-flow is measured.Self-flow is thepercent increase in the diameter of the sample after removingthe Specification C230/C230M cone mold and allowing thespecimen to flow(spread)under it own weight for 120 s.Theconsistency is measured 10 min after water addition.Workingtime may optionally be determined by repeating the self flowtest at regular time intervals.5.Significance and Use5.1 This test method is used to measure the consistency(degree of self-flow)that a castable refractory demonstrates ata given level of tempering liquid at specified time intervalsafter the liquid is added.A self-flow of 25%has been selectedas the minimum at which a mix can be poured into typicalmolds or forms in normal practice.5.2 Castable refractories which are self-flowing at one levelof tempering liquid will require vibration for placement atsome lower level of tempering liquid.At the tempering liquidlevels which require vibration or tamping for placement,thecastable refractory should be characterized using test methodswhich are appropriate for castable refractories designed forvibration placement,such as Test Method C1445.5.3 This test method is not appropriate for determining thepumpability of castable refractories.6.Interferences(Factors Known to Affect Results)6.1 During method development,a ruggedness evaluationwas performed using a castable comprised of 5%cement,17%reactive alumina,and 78%tabular alumina.Several1This test method is under the jurisdiction of ASTM Committee C08 onRefractories and is the direct responsibility of Subcommittee C08.09 on Monolith-ics.Current edition approved July 1,2011.Published August 2011.Originallyapproved in 1999.Previous edition approved in 2007 as C1446 07.DOI:10.1520/C1446-11.2For 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 factors were found to cause statistically significant effects onthe measured results.See ASTM Research Report No.C081016.6.1.1 Amount of Mixing LiquidThe amount of mixingliquid affects the measured results for typical self-flowingcastable refractories unless added by weight to within 6 0.002lb(6 1 g)of the target weight for a 16.52lb(7500-g)sampleweight.The target liquid level is a percentage of the dry weightof the batch.6.1.2 TemperatureDuring ruggedness testing the effect oftemperature was evaluated.The test mix,tempering liquid,androom temperature were controlled to the same targets.Whenthe temperature was raised by 3.5F(70.3 to 73.8F)worki