1、Designation: D 6797 07Standard Test Method forBursting Strength of Fabrics Constant-Rate-of-Extension(CRE) Ball Burst Test1This standard is issued under the fixed designation D 6797; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision,
2、the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method describes the measurement for burstingstrength of woven and knitted textiles taken from
3、rolls of fabricor fabric taken from garments.NOTE 1For the measurement of bursting strength with a hydraulic orpneumatic machine, refer to Test Method D 3786. For the measurement ofthe bursting strength by means of a ball burst mechanism, refer to TestMethod D 37871.2 The values stated in either SI
4、units or U.S. customaryunits are to be regarded as standard, but must be usedindependently of each other. The U.S. customary units may beapproximate.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 s
5、tandard 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:2D 123 Terminology Relating to TextilesD 1776 Practice for Conditioning and Testing TextilesD 2904 Practice for Interlaborat
6、ory Testing of a Textile TestMethod that Produces Normally Distributed DataD 2906 Practice for Statements on Precision and Bias forTextilesD 3786 Test Method for Bursting Strength of TextileFabricsDiaphragm Bursting Strength Tester MethodD 3787 Test Method for Bursting Strength of TextilesConstant-R
7、ate-of-Traverse (CRT) Ball Burst TestD 4850 Terminology Relating to Fabric3. Terminology3.1 For all terminology relating to D13.59, Fabric TestMethods, General, refer to Terminology D 4850.3.1.1 The following terms are relevant to this standard:bursting strength, constantrate-of-traverse (CRT) tensi
8、le test-ing machine, fabric3.2 For all other terminology related to textiles, refer toTerminology D 123.4. Summary of Test Method4.1 Set up the tensile tester for performing the ball burst testin accordance with the manufactures instructions. A specimenof the fabric is securely clamped to the CRE ma
9、chine withouttension to the ball burst attachment. A force is exerted againstthe specimen by a polished, hardened steel ball until ruptureoccurs.5. Significance and Use5.1 This method is used to determine the force required torupture textile fabric by forcing a steel ball through the fabricwith a co
10、nstant-rate-of-extension tensile tester.5.2 This is a new method and therefore the history of data isvery small, however the agreement of within- laboratory datasuggest this method may be considered for acceptance testingof commercial shipments with caution.5.2.1 If there are differences of practica
11、l significance be-tween reported test results for two laboratories (or more),comparative test should be performed to determine if there is astatistical bias between them, using competent statistical assis-tance. As a minimum, samples used for such comparative testshould be as homogeneous as possible
12、, drawn from the samelot of material as the samples that resulted in disparate resultsduring initial testing, and randomly assigned in equal numbersto each laboratory. Other fabrics with established test valuesmay also be used for these comparative tests. The test resultsfrom the laboratories involv
13、ed should be compared using astatistical test for unpaired data, at a probability level chosenprior to the testing series. If bias is found, either its cause must1This test method is under the jurisdiction of ASTM Committee D13 on Textilesand is the direct responsibility of Subcommittee D13.59 on Fa
14、bric Test Methods,General.Current edition approved July 1, 2007. Published August 2007. Originallyapproved in 2002. Last previous edition approved in 2002 as D 679702.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual
15、Book of ASTMStandards 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.be found and corrected, or future test results for that fabricmust be adjusted
16、in consideration of the known bias.6. Apparatus6.1 Tensile Testing Machine3, of the constant-rate-of- exten-sion (CRE) type.6.2 Ball-Burst Attachment3, consisting of a clampingmechanism to hold the test specimen and a steel ball attachedto the moveable member of the tensile tester.6.2.1 The polished
17、 steel ball shall have a diameter of 25.4006 0.005 mm (1.0000 6 0.0002 in.) and shall be sphericalwithin 0.005 mm (0.0002 in.). The ring clamp shall have aninternal diameter of 44.450 6 0.025 mm (1.750 6 0.001 in.).7. Sampling, Selection, and Number of Specimens7.1 Primary Sampling UnitConsider roll
18、s, bolts or piecesof fabric, or cartons of fabric components of fabricated systemssuch as garments to be the primary sampling unit, as appli-cable.7.2 Laboratory Sampling UnitAs a laboratory samplingunit take from the primary sampling unit at least one full-widthpiece of fabric that is1m(1yd)inlengt
19、h along the selvage(machine direction), after removing the first1m(1yd)length.For circular knit fabrics cut a band at least 300 mm (12 in.)wide. When applicable, use the entire fabric component of thefabricated systems.7.3 Test Specimen SelectionFrom each laboratory sam-pling unit, take five test sp
20、ecimens. Specimen preparation neednot be carried out in the standard atmosphere for testing. Labelto maintain specimen identity.7.3.1 When the end-use fabric component of fabricatedsystems is provided, take specimens from different areas. Thatis, if the product is a garment worn on the upper body, t
21、hen takespecimens from the shoulder, shirt tail, shirt back and front,and sleeve.7.3.2 For fabric widths 125 mm (5 in.) or more, take nospecimen closer than 25 mm (1 in.) from the selvage edge.7.3.3 For fabric widths less than 125 mm (5 in.), use theentire width for specimens.7.3.4 Cut specimens rep
22、resenting a broad distribution di-agonally across the width of the laboratory sampling unit. Takelengthwise specimens from different positions across the widthof the fabric. Take widthwise specimens from different posi-tions along the length of the fabric.7.3.5 Ensure specimens are free of folds, cr
23、eases, orwrinkles.Avoid getting oil, water, grease, etc. On the specimenwhen handling.7.3.6 If the fabric has a pattern, ensure that the specimensare a representative sampling of the pattern.7.4 Specimen PreparationAs test specimens from eachlaboratory sampling unit, proceed as follows:7.4.1 For fab
24、rics, cut five specimens at least 125 3 125 mm(5 3 5 in.).7.4.2 Garments may not require cutting if the equipment hasample room to clamp the garment in the apparatus. Fivedeterminations should be made on each garment.8. Conditioning8.1 Bring the specimens (or laboratory samples) from theprevailing a
25、tmosphere to moisture equilibrium for testingtextiles in the standard atmosphere for testing as prescribed inPractice D 1776.9. Procedure9.1 Unless otherwise specified, make all tests on samplesconditioned in the standard atmosphere for testing as specifiedin 8.1.9.2 Place the specimen without tensi
26、on in the ring clampand fasten securely. Start the CRE machine and maintain aspeed of 305 6 13 mm/min (12 6 0.5 in./min). Continue thatspeed until the specimen bursts. Record to the nearest 5 N (1.0lbf) the ball-bursting strength of the specimen.10. Report10.1 State that the specimens were tested as
27、 directed in TestMethod D 6797. Describe the material or product sampled, andthe method of sampling used.10.2 Report the bursting strength of each specimen and theaverage bursting strength of the five specimens from eachlaboratory sample to the nearest 0.5 N (0.1 lbf).11. Precision and Bias11.1 Summ
28、aryBased upon limited information from onelaboratory, the single-operator and within-laboratory compo-nents of variation and critical differences shown in Tables 1and 2 are approximate. These tables are constructed to illustratewhat one laboratory found when all the observations are takenby the same
29、 well-trained operators using the same piece ofequipment and specimens randomly drawn from the sample ofmaterial. For this laboratory, in comparing two averages, thedifferences should not exceed the single-operator precisionvalues shown in Table 2 for the respective number of tests in 95out of 100 c
30、ases. Differences for other laboratories may belarger or smaller.11.2 Single-Laboratory Test DataA single-laboratory testwas run in 1997 in which randomly-drawn samples of twowoven materials were tested. Two operators in the laboratoryeach tested ten specimens from each mate. Five of the tenspecimen
31、s were tested on one day and five specimens weretested on a second day. Analysis of the data was conductedusing Practices D 2904 and D 2906. The components ofvariance for Bursting StrengthConstant-Rate-Of-Extension(CRE) Ball Burst Method expressed as standard deviationswere calculated to be the valu
32、es listed in Table 1.3Apparatus is commercially available.TABLE 1 Grand Average and Components of VarianceExpressed as Standard DeviationsAfor Bursting StrengthConstant-Rate-of-Extension (CRE) Ball Burst Method, lbfGrand Averageand ComponentMaterial 1 Material 2Grand Average 172.2 131.2Single-Operat
33、or Component 8.1 9.0Within-Laboratory Component 0 0AThe square roots of the components of variance are being reported to expressthe variability in the appropriate units of measure rather than as the squares ofthose units of measure.D679707211.3 PrecisionBecause tests were conducted in only onelabora
34、tory estimates of between laboratory precision may beeither underestimated or overestimated to a considerable extentand should be used with special caution. Before a meaningfulstatement can be made about two specific laboratories, theamount of statistical bias, if any, between them must beestablishe
35、d, with each comparison being based on recent dataobtained on specimens taken from a lot of material of the typebeing evaluated so as to be as nearly homogeneous as possibleand then randomly assigned in equal numbers to each of thelaboratories. However when agreed upon between the contrac-tual parti
36、es, for the approximate components of variancereported in Table 1, two averages of observed values may beconsidered significantly different at the 95 % probability levelif the difference equals or exceeds the critical differences listedin Table 2, for Bursting Strength-Constant-Rate-of-Extension(CRE
37、) Ball Burst Method.11.4 BiasThe value of Bursting Strength-Constant-Rate-of-Extension (CRE) Ball Burst Method can only be defined interms of a test method. Within this limitation, Test MethodD 6797 has no known bias.12. Keywords12.1 ball burst; bursting strengthASTM International takes no position
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39、is standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM Int
40、ernational Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown
41、 below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9
42、555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).TABLE 2 Critical Differences for Bursting StrengthConstant-Rate-of-Extension (CRE) Ball Burst Method, lbf, for theConditions NotedAMaterialsNumber of Observationsin Each AverageSingle-OperatorPrecisionWithin-LaboratoryPrecisionMaterial 1 1 22.4 22.42 15.9 15.95 10.0 10.010 7.1 7.1Material 2 1 25.0 25.02 17.7 17.75 11.2 11.210 7.9 7.9AThe critical differences were calculated using t = 1.960, which is based oninfinite degrees of freedom.D6797073
