1、Designation: C411 11Standard Test Method forHot-Surface Performance of High-Temperature ThermalInsulation1This standard is issued under the fixed designation C411; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last re
2、vision. A number 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 Department of Defense.1. Scope1.1 This test method covers the determination of
3、 the perfor-mance of commercial sizes of both block and pipe forms ofthermal insulating materials when exposed to simulated hot-surface application conditions. The term “hot-surface perfor-mance” has reference to a simulated use-temperature test inwhich the heated testing surface is in a horizontal
4、position.1.2 This test method refers primarily to high-temperatureinsulations that are applicable to hot-side temperatures inexcess of 200F (93C). It is used for materials such aspreformed insulations, insulating cements, blankets, and thelike, by proper laboratory preparation of the samples.1.3 The
5、 values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.1.4 This standard does not purport to address all of thesafety concerns, if any, associated
6、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:2C167 Test Methods for Thickness and Density of Blanket orBatt Th
7、ermal InsulationsC168 Terminology Relating to Thermal InsulationC356 Test Method for Linear Shrinkage of PreformedHigh-Temperature Thermal Insulation Subjected to Soak-ing Heat3. Terminology3.1 DefinitionsTerminology C168 shall apply to theterms used in this test method.3.2 Definitions of Terms Spec
8、ific to This Standard:3.2.1 sag, nthe extent of thickness loss of pipe insulation,at the top longitudinal center, due to material fatigue ordecomposition due to elevated temperature.4. Significance and Use4.1 Performance in service is the final measure of value fora thermal insulation, but simulativ
9、e service tests give usefulindications. One type involves application for a specified timeto a surface heated at a temperature approximately that ofintended service, and noting during the test and afterward,changes in the material and its properties. Measurement ofthese changes are used for predicti
10、ng what occurs in service asa result of exposure to temperatures corresponding to those ofthe tests.5. Apparatus5.1 Heating PlateThe heating plate shall consist of acorrosion-resistant and heat-resistant plate with a preferredexposed test area of 36 by 18 in. (914 by 457 mm), but havinga minimum tes
11、t area of 18 by 18 in. (457 by 457 mm). Theheated area shall have an insulated, heated guard area having aminimum width of 3 in. (76 mm) around the entire periphery ofthe test area. The plate shall be supported in a horizontal planeat a sufficient number of points to prevent sagging. It shall beheat
12、ed on the under side by gas or electricity. The surfacetemperature of the plate shall be measured by not less than fivethermocouples. Four of the thermocouples shall be locatedalong the diagonals that extend from the corners of the exposedarea of the plate and at a distance of 6 in. (152 mm) in from
13、each corner. A fifth thermocouple shall be located near thecenter of the test plate area. The temperature at no point ofmeasurement shall vary more than 65%or625F (614C),whichever is less, from the desired temperature. A heatingchamber beneath the heating plate shall be formed to retain theheat gene
14、rated by the heating means. A 6-in. thickness ofinsulation shall form the bottom and the sides, and the heating1This test method is under the jurisdiction ofASTM Committee C16 on ThermalInsulation and is the direct responsibility of Subcommittee C16.31 on Chemical andPhysical Properties.Current edit
15、ion approved May 1, 2011. Published August 2011. Originallyapproved in 1958. Last previous edition approved in 2005 as C411 05. DOI:10.1520/C0411-11.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStanda
16、rds volume information, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.plate shall form the top of the chamber. Two suitable types ofheating plates are shown in Fig. 1
17、and Fig. 2.5.2 Heating PipeThe heating pipe shall consist of acorrosion-resistant and heat-resistant pipe having a length ofnot less than 3 ft (0.9 m) and preferably 6 ft 6 in. (1.98 m). Itshall be supported horizontally. The nominal diameter of thepipe shall preferably be 3 in. (76 mm). The pipe sh
18、all be heatedelectrically with a spiral heating coil placed along the inside ofthe pipe. Supplementary end heaters, and a guard section atleast 3 in. long of the same insulation as that being placed onthe test section, shall also be provided to guard againstexcessive losses from the ends of the test
19、 specimen. (Wherepossible, the use of standard thermal conductivity pipe testapparatus to serve as the heating pipe is recommended.) Thesurface temperature of the pipe shall be measured by means ofthermocouples, not less than one for each 1 ft (0.3 m) of lengthof the test specimen, and located spira
20、lly around the pipe at 90intervals. The test portion of the pipe shall be that area undera full length of a pipe insulation undergoing test. The tempera-ture at any point of measurement on the test portion shall notvary more than 65%or625F (614C), whichever is less,from the desired temperature.5.3 T
21、emperature MeasurementThermocouples shall beused to measure the surface temperature of the heating plateand the heating pipe. They shall be applied either by peeningthe individual wires into small holes drilled into the surface andseparated by not more than18 in. (3 mm) or by joining thewires with a
22、 welded bead and cementing them in grooves withthe bead tangent to the surface but not projecting above it. Thethermocouples shall be made from wires having a size notgreater than No. 22 Awg (0.644 mm), and preferably not largerthan No. 26 Awg (0.405 mm). The combination of thethermocouple and measu
23、ring instrument used shall ensure anaccuracy of temperature measurement of 61%.NOTE 1This requires different thermocouples and measuring instru-ments for high-temperature tests than for moderate-temperature tests.5.4 Straightedge and RuleA straightedge having a lengthof at least 36 in. (0.9 m) and a
24、 small rule divided in164 or110of 1 in. shall be used to determine warpage.6. Sampling and Preparation of Test Specimens6.1 All samples that are required to complete the tests shallbe selected at one time and in such a manner so as to be fullyrepresentative of the average of the material. Test speci
25、mensfor any one test condition shall be selected from the originalsample lot so as to be as representative as possible. The testspecimens shall be commercial pieces. For pipe insulation, thein.mm183146121334191251123825121264211166831289410241116119512713330151239417432184572973730762317874310924511
26、43FIG. 1 Type A Heating Plate for Hot-Surface Performance TestC411 112full-size, commercial pipe sections shall be selected. Anydiameter pipe insulation for which equipment is available ispotentially tested. However, only pipe insulation of 3-in.(76-mm) nominal inside diameter need to be tested.7. P
27、rocedure7.1 Use the heating plate for testing the flat or block form ofinsulation. Use the heating pipe for pipe insulation. Thethickness of the layers in multilayer insulation and the totalthickness of insulation applied to the hot surface for a test shallbe that recommended by the manufacturer for
28、 the temperatureof the hot surface in question, or as agreed between themanufacturer and the purchaser. When multi-layer applicationsare to be tested, stagger each joint between adjacent test piecesin the same layer with respect to the joint in the next layer.Equally dispose about that joint the tes
29、t piece in the next layerthat covers a joint of the preceding layer.7.2 Assembly of Specimen on Heating PlateSpecimensfor testing on a heating plate shall be 6 by 18 in. (152 by 457mm) with the thickness as described in 7.1. Check each blockfor flatness and measure and record any initial warpage. Co
30、verthe test area of the heating plate with the test blocks. If anyblocks have initial warpage, place the concave face toward thehot side. Apply additional layers to the first layers whennecessary to give the total required thickness.7.3 Assembly of Specimen on Heating PipeApply a fulllength of pipe
31、insulation to the test pipe. If the test pipe islonger than the specimen, the latter can advantageously becentered on the pipe and the ends covered with sawed lengthsof the insulation being tested so as to help guard the full lengthspecimen from end losses. The thickness of the test specimenshall be
32、 as required in 7.1.Apply additional layers of insulationas necessary to give the required total thickness. Apply the316 in. = 4.8 mm1 ft = 305 mm24 in. = 610 mm42 in. = 1067 mmNOTE 1Thermocouple leads to temperature controller.FIG. 2 Type B Heating Plate for Hot-Surface Performance TestC411 113vari
33、ous layers of insulation and secure tightly around the pipeby the usual recommended practice.7.3.1 Specimen shall be mounted using aluminum bands orwiring, which shall be tightened until snug. Three bands shallbe used. Band positions shall be at 3, 18, and 33 in. (76, 457,and 838 mm) from the end of
34、 the 36 in. (914 mm) longspecimen.7.3.2 When the sag measurement is required by the materialspecification, measure the starting thickness using a pin gage,as described by Test MethodC167. The pin gage shall bevertically inserted through the top longitudinal center of theinsulation to obtain tip cont
35、act with the pipe surface. The pingage shall be read with a steel rule to the nearest132 in. (1 mm).Using the center band 18 in. (457 mm) as a reference point,measure the starting thickness at 2, 5, and 10 in. (51, 127, 254mm) from center band in both directions.7.4 Use the appropriate heat-up proce
36、dure as specified in thematerial standard. If a heat-up procedure is not specified in thematerial standard, the heat-up procedure in 7.4.1 shall be used.7.4.1 Start the test with the heating surface at room tem-perature. The average temperature rise shall not exceed300F/hr (167C/hr) as described in
37、Test Method C356.7.4.2 For materials that require a heat-up schedule, start thetest with the heating surface at room temperature. Follow thetime-temperature recommendations of the manufacturer forheat-up.7.4.3 For materials that require the test to begin on apreheated test apparatus (slap-on), use a
38、 sacrificial piece of thetest material to bring the test equipment to the target tempera-ture. Once the target temperature has been reached, remove andrapidly replace the sacrificial piece with the test specimen tobegin test.7.5 During the heating period, make qualitative observa-tions to detect vis
39、ible evidence of flaming, glowing, smolder-ing, and smoking. After the hot surface has reached the desiredtest temperature, begin a period of exposure of 96 h. At thecompletion of the test period, turn off the source of heat andallow the assembly to cool to about room temperature beforeany specimens
40、 are removed.NOTE 2Ambient conditions on the exposed surface of the testinsulation shall be at room temperature.7.6 After test and prior to removal, examine the specimensvery carefully to detect any tendency toward cracking. Note thenumber of cracks and the extent or depth of cracking.Also noteany t
41、endency toward delamination. Record other discerniblechanges, such as any evidence of melting, flaming, glowing,smoldering, or smoking that can be observed by visual inspec-tion.7.6.1 WarpageMeasure the block or pipe specimens forwarpage by placing a straightedge along the length of the blockor pipe
42、 and measuring the maximum warpage at the center ofthe specimen with a steel rule.7.6.2 SagThe sag measurement portion of C411 is re-quired only when specifically mentioned by a material stan-dard. When the sag measurement is specifically required by thematerial specification, the thickness shall be
43、 measured beforethe beginning of the C411 hot surface testing and before thespecimens are removed at the end of the C411 hot surfacetesting. Measure final thickness of pipe insulation using a pingage, as described by test method C167. The pin gage shall bevertically inserted through the top longitud
44、inal center of theinsulation to obtain tip contact with the pipe surface. The pingage shall be read with a steel rule to the nearest132 in. (1 mm).Using the center band 18 in. (457 mm) as a reference point,measure the final thickness at 2, 5, and 10 in. from center bandin both directions8. Calculati
45、on8.1 Calculate the amount of warpage due to heating asfollows:W 5 W22 W1(1)where:W = warpage developed during the test, in in. (or mm),(measured in accordance with 7.6),W1= initial measured warpage, in in. (or mm), andW2= final measured warpage, in in. (or mm).8.2 Calculate the amount of thickness
46、sag as follows:% Change 5 t1 t2!/t1! 3100 (2)where:t1= starting thickness (average of 6)t2= final thickness (average of 6)9. Report9.1 Report the following information:9.1.1 Name and any other identification of the materialtested,9.1.2 Kind of insulation tested, sectional, segmental, orblock,9.1.3 N
47、umber of layers of insulation applied,9.1.4 Size and thickness of each layer,9.1.5 Details of application,9.1.6 Temperature of test,9.1.7 Warpage,9.1.8 Sag (average of 6),9.1.9 Extent of cracking,9.1.10 Amount of delamination,9.1.11 Other visible changes,9.1.12 Any evidence of flaming, glowing, smol
48、dering,smoking, melting or dripping, and9.1.13 Details of any heat up schedule if used and whetherspecimen was applied to a cold or hot surface.10. Precision and Bias10.1 Warpage3:10.1.1 PrecisionPrecision of the warpage test method wasdetermined by a round robin with four participating laborato-rie
49、s. The product tested was faced rigid cellular polyisocyanu-rate board with embedded glass mesh, and a density ofapproximately 1.86 lb/ft3(29.80 kg/m3). Facer was removedfrom both sides prior to test. Orientation of the embedded glassmesh did not affect the test results. Temperature of exposure3Supporting data have been filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR:C16-1031.C411 114was 300F (149C), which was above the product use tempera-ture, to achieve measurable warpage and measura