1、Designation: D1518 11aStandard Test Method forThermal Resistance of Batting Systems Using a Hot Plate1This standard is issued under the fixed designation D1518; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revis
2、ion. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.INTRODUCTIONThis standard replaces D1518-85, Thermal Transmittance of Textile Materials. This standardprovides a method for measuring the th
3、ermal resistance (insulation) provided by battings andbatting/fabric systems under still air conditions or an air flow condition. Other hot plate standardsF1868 and ISO 11092 provide a method for measuring the thermal resistance and evaporativeresistance of fabrics and fabric systems. The method for
4、 measuring fabric insulation in these standardsis comparable to Option 2: Air Velocity Condition in D1518. These standards can be used to comparethe thermal properties of textile materials. Manikin standards F1291 and F2370 can be used tomeasure and compare the thermal resistance and evaporative res
5、istance of clothing systems,respectively. Manikin standard F1720 can be used to measure the insulation provided by sleeping bagsystems.1. Scope1.1 This test method covers the measurement of the thermalresistance, under steady-state conditions, of battings andbatting/fabric systems, and other materia
6、ls within the limitsspecified in 1.2. It measures the heat transfer from a warm, dry,constant-temperature, horizontal flat-plate up through a layerof the test material to a cool atmosphere and calculates theresistance of the material. The measurements are made understill air conditions (Option #1) o
7、r with a horizontal air flowover the specimen (Option #2).1.2 For practical purposes, this test method is limited todeterminations on specimens of battings and layered batting/fabric assemblies having an intrinsic thermal resistance from0.1 to 1.5 Km2/W and thicknesses not in excess of 50 mm.1.3 Thi
8、s test method also provides a method for determiningthe bulk density of the material, the insulation per unitthickness, and the insulation per unit weight.1.4 The values stated in SI units are to be regarded asstandard.1.5 This standard does not purport to address the safetyconcerns associated with
9、its use. It is the responsibility ofwhoever uses this standard to consult and establish appropri-ate safety and health practices and determine the applicabilityof regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D123 Terminology Relating to TextilesD3776 Test Methods fo
10、r Mass Per Unit Area (Weight) ofFabricE177 Practice for Use of the Terms Precision and Bias inASTM Test MethodsE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test MethodF1291 Test Method for Measuring the Thermal Insulationof Clothing Using a Heated ManikinF1494
11、 Terminology Relating to Protective ClothingF1720 Test Method for Measuring Thermal Insulation ofSleeping Bags Using a Heated ManikinF1868 Test Method for Thermal and Evaporative Resis-tance of Clothing Materials Using a Sweating Hot PlateF2370 Test Method for Measuring the Evaporative Resis-tance o
12、f Clothing Using a Sweating Manikin2.2 ISO Standards:3ISO 11092 TextilesPhysiological EffectsMeasurement ofThermal and Water-Vapour Resistance Under Steady-State Conditions (Sweating Guarded-Hotplate Test)ISO 9073-2 TextileTest Methods for NonwovensPart2: Determination of Thickness1This test method
13、is under the jurisdiction of ASTM Committee D13 on Textilesand is the direct responsibility of Subcommittee D13.51 on Conditioning and,Chemical and Thermal Properties.Current edition approved July 1, 2011. Published August 2011. Originallypublished as D1518 57 T. Last previous edition approved in 20
14、11 as D1518 11.DOI: 10.1520/D1518-11A.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 ASTM website.3Available from America
15、n National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3. Terminology3.1 The following terms are relevant to this standard: bulkdensity,
16、 clo, thermal resistance, thermal insulation.3.2 For terminology relating to thermal resistance andinsulation see Terminology F1494.3.3 For terminology relating to textiles see TerminologyD123.4. Significance and Use4.1 The thermal resistance of a batting or batting/fabricsystem is of considerable i
17、mportance in determining its suit-ability for use in fabricating cold weather protective clothing,sleeping bags, and bedding systems. The thermal interchangebetween man and his environment is, however, an extremelycomplicated subject which involves many factors in addition tothe insulation values of
18、 fabrics and battings. Therefore, mea-sured thermal insulation values can only indicate relative meritof a particular material.5. Interferences5.1 Departures from the instructions of this test method maylead to significantly different test results. Technical knowledgeconcerning the theory of heat tr
19、ansfer, temperature measure-ment, and testing practices is needed to evaluate whichdepartures from the instructions are significant. Standardiza-tion of the method reduces, but does not eliminate the need forsuch technical knowledge. Report any departures from theinstructions of Test Method D1518 wi
20、th the results.6. Apparatus (Fig. 1, Fig. 2, and Fig. 3)NOTE 1The drawings, illustrations, and captions are provided aspossible design concepts only. The final design of equipment, includingnecessary wiring, will be dictated by the choice of the electrical measuringand control equipment.6.1 Hot Plat
21、eA guarded flat plate composed of a testplate, guard ring, and bottom plate as follows, each electricallymaintained at a constant temperature in the range of humanskin temperature (33 to 38C).6.1.1 Test PlateThe test plate portion of the hot plate shallbe at least 254 mm (10.0 in.) square and shall
22、be placed at thecenter of the upper surface of the hot-plate assembly. It shall bemade of aluminum or copper with a dull black coating toapproximate the emissivity of human skin. The heating ele-ment shall be uniformly distributed over the entire area of thetest plate, mounted within 3 mm (0.1 in.)
23、of the upper platesurface and well-thermally coupled to it.6.1.2 Guard RingThe guard ring bordering the test plateshall be at least 127 mm (5.0 in.) in width and shall be of thesame thickness, composition, and type of construction as thetest plate. It shall be coplanar with the test plate, and shall
24、 beseparated from it by means of a strip of cork or other suitableinsulating material approximately 3-mm (0.1-in.) wide. Theguard ring shall be designed to prevent lateral loss of heat fromthe test plate.6.1.3 Bottom PlateThe bottom plate shall be in a planeparallel to the test plate and guard ring,
25、 and at a distance of atleast 25 mm (1.0 in.) but not in excess of 75 mm (3.0 in.)beneath them. It shall be separated from the test plate andguard ring and the air pocket formed thereby, or by othermeans of causing air entrapment. The dimensions offered assuggested design specifications are shown in
26、 Fig. 3. Thepurpose of the bottom plate is to prevent a downward loss ofheat from the test plate and guard ring.FIG. 1 Hot Plate with Guard Ring and Hood (No Air VelocityMethod)FIG. 2 Hot Plate, Top View, Showing Location of Thermistors andThermocouples on Test Section and Guard RingD1518 11a26.2 Te
27、mperature ControlSeparate independent tempera-ture control is required for the three sections of the hot plate(test plate, guard section, and bottom plate). Temperaturecontrol may be achieved by independent adjustments to thevoltage or current, or both, supplied to the heaters using solidstate power
28、 supplies, solid-state relays (proportional time on),adjustable transformers, variable impedances, or intermittentheating cycles. The test plate, guard, and bottom plate sectionsshall be controlled to measure the same temperature to within60.1C of each other.6.3 Power-Measuring InstrumentsPower to t
29、he hot platetest section shall be measured to provide an accurate averageover the period of the test. If time proportioning or phaseproportioning is used for the power control, then devices thatare capable of averaging over the control cycle are required.Integrating devices (watt-hour transducers) a
30、re preferred overinstantaneous devices (watt meters). Overall accuracy of thepower monitoring equipment must be within 62%ofthereading for the average power for the test period.6.4 Temperature SensorsTemperature sensors shall bethermistors, thermocouples, resistance temperature devices(RTDs), or equ
31、ivalent sensors. The test plate, guard section,and bottom plate shall each contain one or more temperaturesensors that are mounted flush with the hot plate surface orwithin 3 mm of the hot plate surface in such a manner that theymeasure the surface temperature within 60.1C.6.5 Controlled Atmosphere
32、ChamberThe hot plate shallbe housed in an environmental chamber that can be maintainedat selected temperatures between 1 and 20C, or lower (see8.1.2.1.) The test chamber wall temperature shall be 60.5C ofthe air in the chamber. The relative humidity shall be main-tained between 20 and 80 %.6.6 HoodT
33、he hot plate shall be covered with a hood tocontrol air flow.6.6.1 Option 1: Still Air ConditionA box-shaped hoodmade of fabric on a frame with the dimensions shown in Fig.1 is needed to cover the plate so as to maintain still airconditions over the specimen. The fabric cover must bebreathable so th
34、at heat buildup is minimized inside the hood.Thin elastic knits have been successfully used to reduce airvelocity in this application.6.6.2 Option 2: Air Velocity ConditionAn air flow hood isneeded that provides 1.0 m/s of air velocity over the batting/fabric specimen in the horizontal direction. Th
35、e height of theair space above the bare plate or specimen should stay the samefrom test to test. Therefore, the position of the hood needs to beadjustable relative to the plate surface, or the plate surfaceneeds to be adjustable relative to the fixed position of the hoodFIG. 3 Hot Plate Apparatus, S
36、howing DimensionsD1518 11a3to accommodate varying sample thicknesses and to prevent airfrom flowing into the edge of the sample.6.7 Measuring Environmental ParametersThe air tem-perature, relative humidity, and air velocity shall be measuredas follows:6.7.1 Relative Humidity Measuring EquipmentEithe
37、r awet-and-dry bulb psychrometer, a dew point hygrometer, orother electronic humidity measuring device shall be used tomeasure the relative humidity inside the chamber. The relativehumidity sensing devices shall have an overall accuracy of atleast 64%.6.7.2 Air Temperature SensorsAir temperature sen
38、sorswith an overall accuracy of 60.1C shall be used. The sensorsshall have a time constant not exceeding 1 min. Placement ofsensors is described under test conditions for each option.6.7.3 Air Velocity IndicatorFor Option #2, air velocityshall be measured with an accuracy of 60.1 m/s using a hotwire
39、 anemometer. Air velocity is measured at a point 15 mm(nominal) from the plate surface or from the top of the testspecimen surface to the bottom of the anemometer sensingelement. The air velocity shall be measured at three positionslocated along a horizontal line perpendicular to the airflow,includi
40、ng a point at the center of the plate and at points at thecenters of the guard section on both sides of the plate. Spatialvariations in air velocity shall not exceed 610 % of the meanvalue.NOTE 2The air velocity is to be measured 15 mm above the platesurface for bare plate measurements. The air velo
41、city is to be measured 15mm above the test specimen surface when testing fabric or systems. The15 mm distance is to be the distance from the plate or test specimen to theanemometer sensing element (wire)not to the bottom of the sensingelement housing. If the batting system surface is uneven due to q
42、uilting,measure from the samples highest (thickest) point.6.7.4 Air Temperature VariationsAir temperature varia-tions during testing shall not exceed 60.1C6.7.5 Relative Humidity VariationsRelative humidityvariations during testing shall not exceed 64%.6.7.6 Air Velocity VariationsAir velocity varia
43、tions shallnot exceed 65 % of the mean value for data averaged over 1min.7. Sampling and Specimen Preparation7.1 SamplingTest three specimens from each laboratorysampling unit. Indicate whether the specimens are new or havebeen laundered, dry cleaned, or used, or combination thereof.7.2 SpecimensBat
44、tings may be tested alone or a batting/fabric system can be created by placing a cover fabric under thebatting on the plate and on top of the batting during testing.Alternatively, batting/fabric systems can be sewn together theway they would be used in a product. Specimens should be lessthan 50 mm i
45、n thickness.7.3 Specimen PreparationUse test specimens largeenough to cover the surface of the hot plate test section and theguard section completely. Do not compress or stretch battingsamples during handling because this will affect their thicknessand density and the resulting insulation values. Re
46、move anyundesirable wrinkles from fabrics prior to layering them withbattings by smoothing them, flatting them under weights, orsteam ironing them (assuming heat will not damage thefabrics).8. Test Conditions8.1 Option 1: Still Air Condition with Box Hood Over Plate:8.1.1 Temperature of the Test Pla
47、te, Guard Section, andBottom PlateMaintain the temperature of these sections at 356 0.5C and without fluctuating more than 60.1C during atest. The temperature differential between the test plate andguard sections should be maintained within 6 0.2C during atest.8.1.1.1 The standard hot plate temperat
48、ure is 35C; how-ever, thick samples may require a higher plate temperature anda lower air temperature to generate adequate levels of power(heat loss) during a test. Therefore, a higher plate temperaturecan be used, if necessary.8.1.2 Air TemperatureMaintain the air temperature of theair under the ho
49、od between 1 and 15C without fluctuatingmore than 60.1C during a specimen test. Bare plate testsshould be conducted at 20C.8.1.2.1 DiscussionSelect an air temperature that willmaintain a power level within the accurate operating range ofthe instrument while maintaining the plate temperature at35C. Thick samples may require a lower air temperature togenerate adequate levels of power (heat loss) during a test. Thetemperature in the chamber may be several degrees lower thanthe temperature measured inside the box hood because theplate
