ASTM_C_405_-_82_1997.pdf

Designation:C 405 82(Reapproved 1997)Standard Practice forEstimating Consistency of Wet-Mixed Thermal InsulatingCement1This standard is issued under the fixed designation C 405;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(e)indicates an editorial change since the last revision or reapproval.1.Scope1.1 This practice covers estimating the consistency of ther-mal insulating cements,after mixing with a known amount ofwater.The consistency of a wet cement affects such propertiesas ease of trowelling,wet adhesion,drying shrinkage,drydensity,and thermal conductivity.1.2 This practice estimates consistency of thermal insulatingcements in terms of either percentage of deformation asdescribed in Method A or inches of penetration as described inMethod B.1.3 The values stated in inch-pound units are to be regardedas the standard.The values given in parentheses are forinformation only.1.4 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:C 163 Practice for Mixing Thermal Insulating CementSamples2C 168 Terminology Relating to Thermal Insulating Materi-als23.Terminology3.1 DefinitionsExcept for 3.2,Terminology C 168 shallapply to the terms used in this standard.3.2 Definitions of Terms Specific to This Standard:3.2.1 consistencythe degree to which wet-mixed thermalinsulating cement resists deformation due to the application ofoutside forces such as trowel pressure.METHOD ADEFORMATION METHOD4.Apparatus4.1 Dead Load Tester(Fig.1),equipped with two clamps,one of which permits the loading member arm to swivel out ofthe way while the sample is put in position,while the otherkeeps the loading member from sliding until it is released.Thetotal weight of the loading member(sliding vertical bar plus8-in.(203-mm)diameter disk)is adjusted to exactly 5 lb(2.27kg)by adding weights as necessary at the top of the bar.Acylindrical brass mold,3 in.(76.2 mm)in inside diameter by 6in.(152.4 mm)in height,is used to prepare the sample.5.Sample Preparation5.1 Sample at least 3 lb(1.4 kg)of dry cement and mix witha weighed amount of water at a temperature of 70 to 75F(21to 24C)in accordance with Practice C 163.When thoroughlymixed,smooth the cement into a circular mound 3 to 4 in.high(75 to 100 mm)and allowed to sit for 1 h.Then mix once againbefore testing(hydraulic setting cements shall be tested 15 minafter mixing).NOTE1All the water to be mixed with the dry cement shall be addedat one time:tests at other water-cement ratios shall be performed usingentirely new batches of cement mixed in accordance with 5.1.6.Procedure6.1 Oil the inside of the cylindrical mold lightly.Fill themold by throwing 25 to 30 small pieces of wet cement into itwith just enough force to eliminate voids.When the mold isslightly over full,strike off the excess cement level with the topof the mold,with a trowel or spatula;take care not to compressthe cement when this is done.6.2 Center the filled mold under the load member of theapparatus,remove the mold,and place the load member flushon the sample.If the sample deforms(sags)when it is freestanding,still place the load member flush on the sample,andinclude the amount of sag as part of the measured deformation.Release the load member,and measure the deformation 30 slater.6.3 Obtain at least three tests from each batch of wet-mixedcement prepared in accordance with 5.1.7.Calculation7.1 Calculate the percentage deformation for each test asfollows:7.1.1 Inch-Pound Units:Deformation,%56 2 A!/6#3 100(1)1This practice is under the jurisdiction of ASTM Committee C-16 on ThermalInsulation and is the direct responsibility of Subcommittee C16.31 on Chemical andPhysical Properties.Current edition approved June 25,1982.Published August 1982.Originallypublished as C 405 58 T.Last previous edition C 405 60(1979).2Annual Book of ASTM Standards,Vol 04.06.1Copyright ASTM,100 Barr Harbor Drive,West Conshohocken,PA 19428-2959,United States.where:A=height after deformation,in.7.1.2 Metric Units:Deformation,%5152.4 2 A!/152.4#3 100(2)where:A=height after deformation,mm.8.Report8.1 Average the percentage deformations for all tests andreport the average,along with the water-cement ratio used.Ifany single test value differs from the average by more than 65%deformation,discard it and repeat the determination.METHOD BPENETRATION METHOD9.Apparatus9.1 Penetration Tester(Fig.2)The three pointed steelrods or spears have a loose sliding fit in their guides,which are22 in.(559 mm)long.The rods are held up by threeelectromagnets connected to a switch;when the switch isthrown,the three spears are released and drop si