1、Designation: C447 03 (Reapproved 2010)Standard Practice forEstimating the Maximum Use Temperature of ThermalInsulations1This standard is issued under the fixed designation C447; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the y
2、ear 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 estimation of the maximum usetemperature of thermal insulation including loose fill, blank
3、et,block, board, and preformed pipe insulation. It is based uponselected performance criteria, and characterization of productproperties during and after use conditions.1.2 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathematicalconversion
4、s to SI units that are provided for information onlyand are not considered standard.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
5、 determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2C165 Test Method for Measuring Compressive Propertiesof Thermal InsulationsC167 Test Methods for Thickness and Density of Blanket orBatt Thermal InsulationsC168 Terminology Relating to The
6、rmal InsulationC177 Test Method for Steady-State Heat Flux Measure-ments and Thermal Transmission Properties by Means ofthe Guarded-Hot-Plate ApparatusC203 Test Methods for Breaking Load and Flexural Prop-erties of Block-Type Thermal InsulationC302 Test Method for Density and Dimensions of Pre-forme
7、d Pipe-Covering-Type Thermal InsulationC303 Test Method for Dimensions and Density of Pre-formed Block and BoardType Thermal InsulationC335 Test Method for Steady-State Heat Transfer Proper-ties of Pipe InsulationC411 Test Method for Hot-Surface Performance of High-Temperature Thermal InsulationC421
8、 Test Method for Tumbling Friability of PreformedBlock-Type and Preformed Pipe-Covering-Type ThermalInsulationC446 Test Method for Breaking Load and CalculatedModulus of Rupture of Preformed Insulation for Pipes3C518 Test Method for Steady-State Thermal TransmissionProperties by Means of the Heat Fl
9、ow Meter ApparatusD1621 Test Method for Compressive Properties of RigidCellular PlasticsD1622 Test Method for Apparent Density of Rigid CellularPlastics3. Terminology3.1 Definitions C168 shall apply to the terms used in thispractice.4. Summary of Practice4.1 Dimensions, weight and other pertinent pr
10、operties of theinsulation are measured before, during, and after exposure to ahot surface.4.2 Properties during and after exposure, and, in some cases,the degree of change in properties are reported for use inestablishing the maximum service temperature of the insulationmaterial.5. Significance and
11、Use5.1 This practice is intended for use as a guide in evaluatingthe behavior of insulations at elevated temperatures, and injudging suitability for use under the conditions of an intendedapplication. It is not intended for acceptance or certificationtesting on a lot basis.5.2 No single test for est
12、imating maximum use temperaturecan be used that will apply to all types of insulations, nor canany single maximum use temperature be applied to anyinsulation that will be applicable under all possible conditionsof use. Maximum use temperature may depend on thickness,temperature gradient, heating rat
13、e, and other factors. When the1This practice is under the jurisdiction of ASTM Committee C16 on ThermalInsulation and is the direct responsibility of Subcommittee C16.31 on Chemical andPhysical Properties.Current edition approved Nov. 1, 2010. Published January 2011. Originallyapproved in 1959. Last
14、 previous edition approved in 2003 as C447 03. DOI:10.1520/C0447-03R10.2For 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 AST
15、M website.3Withdrawn. The last approved version of this historical standard is referencedon www.astm.org.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.various test methods listed herein are employed, the test resultsserve as guides
16、 and, as such, must be applied with goodengineering judgment in arriving at an acceptable temperaturelimit for the products and applications being considered.5.3 The criteria used to establish acceptable performance isprovided in the material specification or as agreed uponbetween the purchaser and
17、seller.5.4 In most cases, the properties covered by the applicablematerial standards (for example, thermal transmission,strength, etc.) are the properties important to the end use of theproduct. Major changes in those properties resulting fromin-service conditions can cause failure or substandard pe
18、rfor-mance of the installed system.5.5 Unless removal and reuse of the insulation is an impor-tant consideration, properties that relate primarily to handlingand installation shall be eliminated from the evaluation.NOTE 1Installation assemblies: some systems create conditions thatwill affect the per
19、formance from the data obtained in the test proceduresof this practice.5.6 The listing of a test procedure in this practice does notimply that the performance of that particular procedure isrequired. Only those tests which are relevant to the require-ments of the application involved, or which are a
20、greed uponbetween the purchaser and the seller are preformed.5.7 Most of the changes that occur in the functionallyimportant characteristics of all types of thermal insulationduring service result from changes in the matrix or bindersystem first, followed by changes in the bulk filler materialswhere
21、 such fillers have been used.5.7.1 In general, these changes are temperature-dependentand the major portion of the change takes place fairly quicklyonce the critical temperature has been reached.5.7.2 Typically, organic thermoplastic materials or binderswill change in the 140 to 240F (60 to 116C) te
22、mperaturerange. Thermosetting organic materials or binders will start todeteriorate above 350F (177C). Hydrated inorganic binderssuch as clays, portland and lumnite cements, gypsum, sodiumsilicates, oxysulfates, and oxychlorides will lose varyingamounts of water of crystallization at temperatures fr
23、om 250 to900F (121 to 482C) dependent on the compound involved.Glass fibers and glass foams may start to sinter around 1000F(538C). Rock or slag wools, perlites and refractory fibers mayshow change at temperatures in excess of 1300F (704C)dependent on specific composition.5.8 If, after testing sampl
24、es exposed to the maximumservice temperature, additional tests are made of samplesexposed to intermediate temperatures (third or quarter points inthe full service temperature range), the results of such tests,when plotted with proper curve fit techniques, may give someindication of changes in produc
25、t characteristics throughout theservice range. These results may also be used to bracket thetemperature range within which a change has occurred (sig-nificant change in slope of curve).5.9 Some properties of thermal insulations containingtrapped gases other than air change with time, and at differen
26、trates, depending upon the age, thickness, facing and boundaryconditions. Elevated temperature exposure accelerates thesechanges. Changes in properties of these materials may continueover a very long period of time, however, and it is beyond thescope of this recommended practice to establish a minim
27、umtime period for evaluation of these long-term changes.6. Test Conditions6.1 If required, testing shall begin at the hot face tempera-ture of the desired application or that claimed as the maximumuse temperature. When there has been significant deteriorationof the properties tested during or after
28、exposure at themaximum hot face temperature, additional specimens will beexposed at lower temperatures (third or quarter points of thetemperature range from ambient to maximum) to establish thecritical temperature. Additional tests shall be made untilenough data have been obtained to establish accep
29、table perfor-mance.6.2 The criteria necessary to establish acceptable perfor-mance by any of the methods described shall be as provided inthe material specification or as agreed upon between thepurchaser and seller. For example, a minimum value ofcompressive strength or a maximum percent dimensional
30、change might be specified as the criterion for estimating themaximum use temperature.6.3 With anisotropic materials that are produced initially inlarge cross-sections and mechanically fabricated in subsequentoperations to produce boards or preformed pipe insulation, it isadvisable to examine propert
31、ies of interest in all three axes.6.4 Since soaking heat exposure seldom occurs under “asinstalled” conditions, and such exposure will produce resultsthat may be misleading, samples shall be conditioned usinghot-face-/cold-face methods rather than soaking heat. Soakingheat exposure should be limited
32、 to preliminary evaluation andquality control testing.6.5 The elevated temperature exposure time required toeffect major change will vary with the generic type of productbeing tested. Preliminary trials shall be made to establish theminimum hot surface exposure time required for a particularinsulati
33、on material. The minimum exposure time has beenreached when the property of interest shows no more thanexpected random variations in three consecutive readings takenat three hour intervals.7. Test Specimens7.1 The test specimens shall be selected to be representativeof the material under evaluation.
34、 Original surfaces shall beretained at least on the hot face of the specimens.7.2 Other specimen dimensions shall conform to the re-quirements of Test Method C411. Where further fabrication ofthe specimen after exposure is not practical, additional speci-mens, precut to the required size, shall be e
35、xposed separately.8. Procedure8.1 Hot Surface PerformanceTest and report the hotsurface performance of the insulation in accordance with TestMethod C411 with the following exceptions and additions.8.1.1 The thickness of the test specimens shall be theintended thickness of the application or the manu
36、facturersrecommended minimum and maximum thickness for the testtemperature. The number of layers of insulation exposed andC447 03 (2010)2tested shall be representative of the intended application or themanufacturers recommendation at the test thickness.8.1.2 Unless a specific heat-up period is dicta
37、ted by theintended application, included in the material specification orrecommended by the manufacturer, the apparatus shall bepreheated to the test temperature using a blank specimen ofsimilar thermal transmission properties. Once the test tempera-ture has been reached, the blank specimen shall be
38、 removedand the test specimen(s) quickly applied to the hot surface.8.1.3 The hot face temperature shall be the service tempera-ture being evaluated; 0,+5%.8.1.4 Where specific fastening methods are dictated by thematerial specification, the insulation shall be held against thehot surface by means r
39、epresenting these fastening methods, forexample, screws, exterior frames, etc. The attachment methodshall be included in the report.8.1.5 Measure and report the dimensions and weight of thespecimens before and after exposure. Suitable measuringinstruments and procedures can be found in Test MethodsC
40、167, C303 or D1622, and C302 for blankets or felt, block orboard, and preformed pipe insulation respectively. Dimensions,and changes in dimensions, of the hot and cold faces shall bemeasured and reported separately.8.1.6 Record the temperature rise during heat-up at 1-in.(25-mm) increments through t
41、he thickness of the specimen asan indication of endothermic or exothermic reactions withinthe insulation. Temperature shall be recorded continuously, orat a maximum interval of 5 min, until equilibrium is reached.Suitable temperature sensors with a maximum response time of1 min and an accuracy of +
42、/ 1 % shall be used. The sensorsshall be located at the top center of the specimen for preformedpipe covering.8.2 Thermal Transmission PropertiesTest and report thethermal transmission properties of the insulation in accordancewith Test Methods C177 and C518 for blanket, felt, block orboard insulati
43、on or Test Method C335 for preformed pipeinsulation.8.2.1 The test thickness shall be 112 612 in. (38 6 13 mm)for Test Methods C177 and C518. For Test Method C335 thetest thickness is adjusted as required to achieve the proper coldface temperature.8.2.2 The hot face temperature shall be the service
44、tempera-ture being evaluated; 0,+5%.8.2.3 The cold face temperature shall be representative ofthe intended application or a maximum of 200F (93C).8.2.4 Prior to measurement the specimens shall be exposedon the test apparatus at the test temperature for the minimumperiod determined in 6.5. Separate h
45、ot surface exposure is notrequired.NOTE 2Where cyclic operating conditions are anticipated, it isprudent to confirm thermal transmission properties at lower temperaturesfollowing exposure to the maximum hot face temperature.8.3 Other PropertiesTest and report the other pertinentproperties of the ins
46、ulation following hot surface exposure.8.3.1 Specimens shall be obtained from material exposed inaccordance with 7.1. Where further fabrication after exposureis not possible, additional specimens precut to the required sizeare exposed separately maintaining the thickness and otherexposure parameters
47、 of 7.1.8.3.2 The full thickness of the exposed specimen shall betested. Where it is impractical to test the specimens at fullthickness, they may be carefully slit to two or more layers. Theresults of tests on each layer shall be reported separately andidentified as to the original location through
48、the thickness fromhot to cold face.8.3.3 Where it is useful to compare the properties of theinsulation material before and after exposure, the specimensused for“ before exposure” tests shall be of the same size andselected from similar material as those used for the “afterexposure” test.8.3.4 Depend
49、ing on the application, the following propertiesare useful in estimating the suitability of the insulation follow-ing exposure to the test service temperature. Additional perti-nent properties are found in the applicable material specifica-tion and the manufacturers literature. The provisions ofSection 5 shall be considered in selecting properties for testing.8.3.4.1 Compression PropertiesTest Method C165 or TestMethod D1621.8.3.4.2 Flexural StrengthTest Methods C203, TestMethod C446.8.3.4.3 Water/Moisture Absorption/Repellency/WickingAbilityRefer to t
