1、Designation:C41908(Reapproved 2013)Standard Practice forMaking and Curing Test Specimens of Mastic ThermalInsulation Coatings1This standard is issued under the fixed designation C419;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,th
2、e 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 practice covers the preparation of specimens ofmastics and coatings in the form of cured sheets or films tha
3、tmay be used in other procedures for evaluation of physicalproperties.1.2 Three procedures are described for casting and curing(Note 1)mastics and coatings of all types for thermal insula-tion.NOTE1The term“cure”is used primarily to denote the condition thatdevelops as the result of loss of volatile
4、 matter but also to denote possiblesubsequent changes in chemical or physical properties due to crosslinking.1.2.1 Procedure A is intended to provide a specimen ofcontrolled thickness applied to insulation,and equivalent inother respects to that obtainable under field application condi-tions.The the
5、rmal insulation intended for field use may bespecified as the backing.1.2.2 Procedure B is intended to provide a free-film speci-men of controlled thickness having smooth surfaces on bothsides.This type is required for some types of physical testing.1.2.3 Procedure C is intended to provide a free-fi
6、lm speci-men of controlled thickness having one smooth surface(asfield applied).1.3 The procedures of this practice are not intended for theevaluation of application properties.These are covered in TestMethods C461 and Guide C647.1.4 The values stated in inch-pound units are to be regardedas standar
7、d.The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.1.5 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
8、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:2C168 Terminology Relating to Thermal InsulationC461 Test Methods for Mastics and Coatings Used WithThermal InsulationC533 Specificat
9、ion for Calcium Silicate Block and PipeThermal InsulationC647 Guide to Properties and Tests of Mastics and CoatingFinishes for Thermal InsulationD6/D6M Test Method for Loss on Heating of Oil andAsphaltic Compounds3.Terminology3.1 DefinitionsFor definitions used in this practice seeTerminology C168.4
10、.Summary of Practice4.1 Mastics and coatings are applied by a metal blade tothermal insulation backing material in a thickness regulated byguide bars.Moderate heat is applied to the specimens to dry orotherwise cure them.5.Significance and Use5.1 The method of preparation of test specimens of mastic
11、thermal insulation coatings can have an impact upon valuesobtained during testing.Testing laboratories should follow thispractice to help ensure the reproducibility of test methods forwhich a cured sheet or film of a mastic thermal insulationcoating is required.6.Apparatus6.1 Guide BarsTwo rectangul
12、ar steel bars of thicknessequal to the desired wet thickness of the applied mastic orcoating.The guide bars shall be equal in length to the totallength of the specimens.For use on relatively soft backingmaterial,the guide bars may be equipped with pins projecting1This practice is under the jurisdict
13、ion of ASTM Committee C16 on ThermalInsulation and is the direct responsibility of Subcommittee C16.33 on InsulationFinishes and Moisture.Current edition approved Nov.1,2013.Published March 2014.Originallyapproved in 1958.Last previous edition approved in 2008 as C419 08.DOI:10.1520/C0419-08R13.2For
14、 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 Co
15、nshohocken,PA 19428-2959.United States1 from the lower surface at each end,which can be forced intothe backing to hold the bars in position during preparation ofthe test specimen.6.2 Strike-Off BarA flat strip of rigid metal,not less than2 in.(51 mm)greater in length than the width of the specimen.O
16、ne edge shall be smooth and straight.6.3 Leveling RollerOne section of straight 112-in.(38-mm)stainless steel pipe or any other convenient cylindricalleveling tool.The tool shall have a smooth surface.Minimumlength shall be 2 in.(51 mm)longer than the width of thespecimen.6.4 Backing MaterialUnless otherwise specified by theprocedure for the test to be made,the backing for the specimenshall consist of commercial block-type calcium silicate insula-tion meeting the requirements of Specification C5
