1、Designation: C 165 07Standard Test Method forMeasuring Compressive Properties of Thermal Insulations1This standard is issued under the fixed designation C 165; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revisi
2、on. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) 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 two procedures for dete
3、rminingthe compressive resistance of thermal insulations.1.1.1 Procedure A covers thermal insulations having anapproximate straight-line portion of a load-deformation curve,with or without an identifiable yield point as shown in Figs. 1and 2. Such behavior is typical of most rigid board orblock-type
4、 insulations.1.1.2 Procedure B covers thermal insulations that becomeincreasingly more stiff as load is increased, as shown in Fig. 3.Such behavior is typical of fibrous batt and blanket insulationsthat have been compressed previously to at least the samedeformation by compression packaging or mecha
5、nical soften-ing.1.2 It is recognized that the classification of materials underProcedures A and B shall not hold in all cases. For example,some batt or blanket materials that have not been compressionpackaged will exhibit behavior more typical of ProcedureAfortheir first loadings.Also, some higher
6、density fibrous insulationboards that have been precompressed will exhibit load-deformation curves more typical of Procedure B. There willalso be thermal insulations with load-deformation curves thatfollow none of the three types shown here; that is, curves withno straight-line portion, curves with
7、compaction areas, andcurves that change from negative to positive slope.1.3 This test method does not cover reflective or loose fillinsulations.1.4 The values stated in inch-pound units are to be regardedas the standard. The values given in parentheses are forinformation only.1.5 This standard does
8、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 Standa
9、rds:2C 167 Test Methods for Thickness and Density of Blanketor Batt Thermal InsulationsC 168 Terminology Relating to Thermal InsulationC 240 Test Methods of Testing Cellular Glass InsulationBlockE4 Practices for Force Verification of Testing MachinesE 177 Practice for Use of the Terms Precision and
10、Bias inASTM Test MethodsE 691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method3. Terminology3.1 Definitions:1This test method is under the jurisdiction ofASTM Committee C16 on ThermalInsulation and is the direct responsibility of Subcommittee C16.32 on Mech
11、anicalProperties.Current edition approved May 1, 2007. Published May 2007. Originallyapproved in 1941. Last previous edition approved in 2005 as C 165 05.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMS
12、tandards volume information, refer to the standards Document Summary page onthe ASTM website.FIG. 1 Procedure AStraight Line Portion with Definite YieldPoint1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3.1.1 Terminology C 168 appl
13、ies to the terms used in thismethod.3.2 Additional terms are defined as follows:3.3 compressive deformationthe decrease in specimenthickness by a compressive load.3.4 compressive loadthe compressive force carried by thetest specimen at any given moment.3.5 compressive modulus of elasticitythe ratio
14、of thecompressive load per unit of original area to the correspondingdeformation per unit of original thickness below the propor-tional limit of a material.3.6 compressive resistancethe compressive load per unitof original area at a specified deformation. For those materialswhere the specified defor
15、mation is regarded as indicating thestart of complete failure, the compressive resistance mayproperly be called the compressive strength.3.7 proportional limit in compressionthe greatest com-pressive load that a material is capable of sustaining withoutany deviation from proportionality of load to d
16、eformation.3.8 yield point in compressionthe load at the first point onthe load-deformation curve at which an increase in deformationoccurs without an increase in load.4. Significance and Use4.1 In providing Procedures A and B, it is recognized thatdifferent types of thermal insulation will exhibit
17、significantlydifferent behavior under compressive load. Data must usuallybe obtained from a complete load-deformation curve, and theuseful working range normally corresponds to only a portion ofthe curve. The user is cautioned against use of the product inthe range beyond which the product is perman
18、ently damaged orproperties are adversely affected.4.2 Load-deformation curves provide useful data for re-search and development, quality control, specification accep-tance or rejection, and for other special purposes. Standardloading rates shall not be used arbitrarily for all purposes; theeffects o
19、f impact, creep, fatigue, and repeated cycling must beconsidered. All load-deformation data shall be reviewed care-fully for applicability prior to acceptance for use in engineeringdesigns differing widely in load, load application rate, andmaterial dimensions involved.5. Apparatus5.1 Testing Machin
20、e Standard hydraulic or mechanicalcompression testing machine of suitable capacity, and capableof operating at the specified constant rate of motion of themovable head. Verify the accuracy of the testing machine inaccordance with Practices E4.5.2 Loading Surfaces Surfaces shall be at least 1.0 in.(2
21、5.4 mm) greater in all directions than the test specimens, andshall be designed to remain plane within 60.003 in./ft (60.25mm/m) under all conditions of load.5.2.1 Procedure A A preferred size is 8.0 in. (203 mm)square. One surface plate, either the upper or lower, shall bemounted rigidly with its s
22、urface perpendicular to the testingmachine axis. The other surface plate shall be self-aligning,suspended by a spherical bearing block as shown in Fig. 4.5.2.2 Procedure BApreferred size is 1.0 ft2(0.093 m2)inarea, either 12 in. (305 mm) square or 13.54 in. (344 mm) indiameter. Both plates shall be
23、mounted rigidly so that thesurfaces are parallel to each other and perpendicular to thetesting machine axis.5.3 Load Indicator Load-indicating mechanism that willpermit measurements with an accuracy of6 1 % of total load.5.4 Deformation IndicatorDeformation-indicatingmechanism that measures crosshea
24、d movement, or a simple jigthat will permit direct measurements, with an accuracy of60.1 % of specimen thickness. When crosshead movement isused to measure deformation, use a calibration curve unless ithas been shown that under the conditions of test the crossheadindicator gives an accurate measure
25、of specimen deformation.FIG. 2 Procedure AStraight Line Portion but no Definite YieldPointFIG. 3 Procedure BIncreasing StiffnessFIG. 4 Spherical Bearing Block for Compressive Strength TestC1650725.5 Measuring Instruments:5.5.1 Dial Gage Comparator, with a circular foot having aminimum area of 1.00 i
26、n.2(645 mm2) and capable of measur-ing thickness to 60.002 in. (60.05 mm).5.5.2 Steel Rule, capable of measuring to 60.01 in. (0.25mm).5.5.3 Depth Gage, pin-type, as specified in Test MethodsC 167 for Procedure B only.5.6 Drying or Conditioning Equipment (see 6.5):5.6.1 Drying Oven, temperatures to
27、250F (121C).5.6.2 Desiccator, using dry calcium chloride or silica geldesiccant.5.6.3 Conditioned Space, at temperature of 73.4 6 3.6F(23 6 2C), and relative humidity of 50 6 5%.6. Test Specimens6.1 Specimen Size:6.1.1 Procedure A specimens shall preferably be square orcircular with a minimum area o
28、f 4 in.2(2580 mm2) and apreferred width or diameter of 6 in. (150 mm). The minimumthickness shall be12 in. (12.7 mm) and the maximum thicknessshall be no greater than the width or diameter.NOTE 1See Test Methods C 240 for preparation of cellular glass testspecimens.6.1.2 Procedure B specimens shall
29、preferably be square orcircular with a minimum width or diameter of 6.0 in. (153mm). The minimum thickness shall be 1.0 in. (25.4 mm) andthe maximum thickness shall be no greater than the width ordiameter.NOTE 2For some materials, the specimen thickness has considerableeffect on the deformation at y
30、ield, the compressive resistance, and thecompressive modulus. Therefore, use the same thickness for comparisonswith other test specimens. The thinner the specimen, the higher thecompressive resistance and the lower the deformation at yield.6.2 The number of specimens to be tested and the samplingpla
31、n shall conform to materials specifications where appli-cable. In the absence of such specifications the minimumnumber of specimens shall be at least four, chosen at random torepresent the lot.6.3 The specimens shall be cut from larger blocks orirregular shapes in such a manner as to preserve as man
32、y of theoriginal surfaces as possible. The bearing faces of the testspecimens shall be plane, parallel to each other, and perpen-dicular to the sides. Where the original surfaces of the block aresubstantially plane and parallel, no special preparation of thesurfaces will usually be necessary. In pre
33、paring specimensfrom pieces of irregular shape, any means that will produce aspecimen with plane and parallel faces without weakening thestructure of the specimen shall be used.6.4 The specimens shall be prepared so that the direction ofloading will be the same as that on the insulation in service.
34、Ifthe direction of loading in service is unknown and the materialis suspected of being anisotropic, different sets of test speci-mens shall be prepared with compression axes parallel to thedifferent directions of loading that might occur.6.5 The specimens shall be dried and conditioned prior totest,
35、 following applicable specifications for the material. If thematerial is affected adversely by oven temperatures, the speci-mens shall be conditioned for not less than 40 h at 73.4 6 1.8F(23 6 1C), and 50 6 5 % relative humidity before testing. Inthe absence of definitive drying specifications, the
36、specimensshall be dried in an oven at 215 to 250F (102 to 121C) toconstant mass and held in a desiccator to cool to roomtemperature before testing. Where circumstances or require-ments preclude compliance with these conditioning proce-dures, exceptions agreed upon between the manufacturer andthe pur
37、chaser shall be specifically listed in the test report.7. Procedures7.1 Procedure A:7.1.1 Measure the specimen dimensions within 61 %. Eachdimension shall be the average of at least two measurementstaken on each specimen face. Use the steel rule and the dialgage comparator as appropriate.7.1.2 Place
38、 the specimen between the loading surfaces ofthe testing machine, taking care that the centerline of thespecimen coincides with the centerline of the testing machineso that the load will be uniformly distributed. The self-aligningsurface shall be approximately parallel to the fixed plate. Keepthe sp
39、herical bearing seat well lubricated to ensure freemovement.7.1.3 Adjust the crosshead speed to the value specified forthe material being tested. This shall not exceed the range from0.01 to 0.5 in./min (0.25 to 12.7 mm/min) for each 1 in. (25.4mm) of specimen thickness. In the absence of such specif
40、ica-tion, the speed shall be 0.05 in./min (1.27 mm/min) for each 1in. of specimen thickness.NOTE 3The speed of crosshead travel will have considerable effect onthe compressive resistance value. In general, higher crosshead speedsusually result in higher compressive resistance values. Take this intoa
41、ccount in selecting crosshead speed other than standard when comparingdifferent types of thermal insulation.7.1.4 To reduce the time for the loading head to contact thetest specimen, the crosshead shall be moved at a rapid untilcontact with the specimen is made. This will cause a slightpreload to be
42、 applied to the specimen. Change the loadingspeed to the required value once contact is made. This preloadshall not be more than 2% of the load at the final deformation.NOTE 4If this test method is used in specifications or by specifiers tocharacterize the compressive resistance of a material, any p
43、reload valueused must be specified.7.1.5 Compress the specimen to the desired deformation.Record the loads and deformations at points that will ad-equately describe a load-deformation curve.7.2 Procedure B:7.2.1 Measure the specimen face dimensions within 61%using the steel rule. Each dimension shal
44、l be the average of atleast two measurements taken on each specimen face.7.2.2 Measure the specimen thickness to 61 %. Use thepin-type depth gage and follow Test Methods C 167 if thematerial is pin-penetrable. If it is not, use the dial gagecomparator. Average three measurements.7.2.3 Place the spec
45、imen between the loading surfaces ofthe testing machine, taking care that the centerlines of thespecimen and the testing machine coincide.C1650737.2.4 Adjust the crosshead speed to a maximum of 5 in./min(125 mm/min), but follow material specifications if a differentspeed is specified (see Note 3 abo
46、ve).7.2.5 Compress the specimen to the desired deformation ofeither 10 or 25 % of the thickness measured in 7.2.2 or of thenominal thickness if so specified. To reduce variability insample sets with densities greater than 3 lbs/ft3(48 kg/m3), theinitial deformation point on the load curve must be ch
47、osen at afixed preload. Preload values shall be less than 2 % of the loadat 10 % deformation.NOTE 5If this test method is used in specifications or by specifiers tocharacterize the compressive resistance of a material, any preload value tobe used must be specified.8. Calculations8.1 Procedure A:8.1.
48、1 Construct a load-deformation curve.8.1.2 Using a straightedge, carefully extend to the zero loadline the steepest straight portion of the load-deformation curve.This establishes the “zero deformation point.” Measure alldistances for deformation calculations from this point (Point 0in Figs. 5 and 6
49、).8.1.3 Measure from Point 0 along the zero load line adistance representing 5 %, 10 %, or other specified deforma-tion. At that point (Point M in Figs. 5 and 6), draw a verticalline intersecting the load deformation curve at Point P. If thereis no yield point before Point P (as in Fig. 6), read the load atPoint P. If there is a yield point before Point P (as Point L inFig. 5), read the load and measure the percent deformation(distance O-R) at the yield point.8.1.4 Calculate the compressive resistance as follows:S 5 W/A (1)where:S = compressive resistance