ASTM D5034-2008 Standard Test Method for Breaking Strength and Elongation of Textile Fabrics (Grab Test).pdf

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1、Designation: D 5034 08Standard Test Method forBreaking Strength and Elongation of Textile Fabrics (GrabTest)1This standard is issued under the fixed designation D 5034; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of la

2、st 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 test method covers the grab and modified grab testprocedures for determining the breaking strength and elonga-tion

3、of most textile fabrics. Provisions are made for wet testing.1.1.1 The grab test procedure is applicable to woven,nonwoven, and felted fabrics, while the modified grab testprocedure is used primarily for woven fabrics.1.2 This test method is not recommended for glass fabrics,or for knitted fabrics a

4、nd other textile fabrics which have highstretch (more than 11 %).NOTE 1For the determination of the breaking force and elongation oftextile fabrics using the raveled strip test procedure and the cut strip testprocedure, refer to Test Method D 5035.1.3 This test method provides the values in both inc

5、h-poundunits and SI units. Inch-pound units is the technically correctname for the customary units used in the United States. SI unitsis the technically correct name for the system of metric unitsknown as the International System of Units. The values statedin either acceptable metric units or in oth

6、er units shall beregarded separately as standard. The values stated in eachsystem may not be exact equivalents; therefore, each systemmust be used independently of the other, without combining inany way.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with

7、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:2D76 Specification for Tensile Testing Machines for TextilesD 123 Term

8、inology Relating to TextilesD 629 Test Methods for Quantitative Analysis of Textiles3D 1059 Test Method for Yarn Number Based on Short-Length SpecimensD 1776 Practice for Conditioning and Testing TextilesD 5035 Test Method for Breaking Force and Elongation ofTextile Fabrics (Strip Method)D 4850 Term

9、inology Relating to Fabric3. Terminology3.1 For all terminology relating to D13.60, Fabric TestMethods, Specific, refer to Terminology D 4850.3.1.1 The following terms are relevant to this standard:breaking force, braking load, constant-rate-of-extension (CRE)tensile testing machine, constant-rate-o

10、f-traverse (CRT) tensiletesting machine, elongation, extension, grab test modified grabtest, tensile test.3.2 For all other terminology related to textiles, refer toTerminology D 123.4. Summary of Test Method4.1 A 100-mm (4.0-in.) wide specimen is mounted centrallyin clamps of a tensile testing mach

11、ine and a force applied untilthe specimen breaks. Values for the breaking force and theelongation of the test specimen are obtained from machinescales, dials, autographic recording charts, or a computerinterfaced with the testing machine.4.2 This test method describes procedures for carrying outfabr

12、ic grab tensile tests using two types of specimens and threealternative types of testing machines. For reporting, use thefollowing identification system of specific specimen and ma-chine combinations.4.2.1 Type of specimen:4.2.1.1 GGrab4.2.1.2 MGModified grab4.2.2 Type of tensile testing machine:4.2

13、.2.1 EConstant-rate-of-extension (CRE)4.2.2.2 LConstant-rate-of-load (CRL)4.2.2.3 TConstant-rate-of -traverse (CRT)1This test method is under the jurisdiction of ASTM Committee D13 on Textilesand is the direct responsibility of Subcommittee D13.60 on Fabric Test Methods,Specific.Current edition appr

14、oved June 1, 2008. Published July 2008. Replaces GrabTesting sections of Test Method D 1682 90. Originally approved in 1990. Lastprevious edition approved in 2001 as D 503495(2001).2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.or

15、g. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Withdrawn.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.4.2.3 Possible combinations can be identified as follo

16、ws:Test SpecimenType of TesterConstant-Rate-of-ExtensionConstant-Rate-of-LoadConstant-Rate-of-TraverseGrab G-E G-L G-TModified Grab MG-E MG-L MG-TFor example, Test Method D 5034, G-E refers to a grab test carried out on aconstant rate-of-extension tensile testing machine.5. Significance and Use5.1 T

17、he grab test procedure in this test method for thedetermination of breaking force and elongation is consideredsatisfactory for acceptance testing of commercial shipments ofmost woven or nonwoven textile fabrics, and the modified grabtest procedure is considered satisfactory for acceptance testingof

18、commercial shipments of most woven textile fabrics, sincethe procedures have been used extensively in the trade foracceptance testing.5.1.1 In case of disagreement arising from differences inreported test values when using this test method for acceptancetesting of commercial shipments, the purchaser

19、 and the sup-plier should conduct comparative tests to determine if there isa statistical bias between their laboratories. Competent statis-tical assistance is recommended for the investigation of bias.As a minimum, the two parties should take a group of testspecimens which are as homogeneous as pos

20、sible and whichare from a lot of material of the type in question. The testspecimens should then be randomly assigned in equal numbersto each laboratory for testing. The average results from the twolaboratories should be compared using Students t-test forunpaired data and an acceptable probability l

21、evel chosen by thetwo parties before testing is begun. If a bias is found, either itscause must be found and corrected, or the purchaser and thesupplier must agree to interpret future test results in light of theknown bias.5.2 This test method is not recommended for knitted fabricsbecause of their h

22、igh stretch.5.3 Some modification of technique may be necessary forany fabric having a strength in excess of 200-N/cm (1140-lb/in.) width. Special precautionary measures are provided for usewhen necessary for strong fabrics.5.4 All of the procedures are applicable for testing fabricseither condition

23、ed or wet.5.5 Comparison of results from tensile testing machinesoperating on different principles is not recommended. Whendifferent types of machines are used for comparison testing,constant-time-to-break at 20 6 3 s is the established way ofproducing data. Even then the data may differ significant

24、ly.5.6 Although a constant-rate-of-extension is preferred inthese procedures, in cases of dispute, unless there is agreementto the contrary between the purchaser and the supplier, aconstant-time-to-break (20 6 3 s) is to be used.5.7 The grab test procedure is applicable to the determina-tion of the

25、effective strength of the fabric; that is, the strengthof the yarns in a specific width together with the fabricassistance from the adjacent yarns. The breaking force deter-mined by the grab procedure is not a reflection of the strengthof the yarns actually gripped between clamps and cannot beused f

26、or direct comparison with yarn strength determinations.Grab test specimens require much less time to prepare althoughthey require more fabric per specimen. There is no simplerelationship between grab tests and strip tests since the amountof fabric assistance depends on the type of fabric and constru

27、c-tion variables.5.8 The modified grab test procedure is applicable to thedetermination of the breaking force of fabrics with construc-tions in which the application of tensile stress on raveled stripspecimens produces further unraveling. This test method isparticularly applicable to high-strength f

28、abrics.6. Apparatus, Reagents, and Materials6.1 Tensile Testing Machine, of the CRE, CRL, or CRT typeconforming to Specification D76, with respect to force indi-cation, working range, capacity, and elongation indicator, anddesigned for operation at a speed of 300 6 10 mm/min (12 60.5 in./min); or, a

29、 variable speed drive, change gears, orinterchangeable weights as required to obtain the 20 6 3-stime-to-break (see 5.5 and 5.6).6.2 Clamps and Jaw FacesEach jaw face shall be smooth,flat, and with a metallic, or other agreed upon, gripping surface.The faces shall be parallel and have matching cente

30、rs withrespect to one another in the same clamp and to the corre-sponding jaw face of the other clamp.6.2.1 For grab tests, each clamp shall have a front (or top)jaw face measuring 25 6 1 mm (1.0 6 0.02 in.) perpendicularto the direction of the application of the force, and not less than25 nor more

31、than 50 mm (1.0 nor more than 2.0 in.) parallel tothe direction of the application of the force (Note 2). The back,or bottom, jaw face of each clamp shall be at least as large asits mate. Use of a larger face for the second jaw reduces theproblem of front and back jaw face misalignment.NOTE 2Front (

32、or top) faces measuring 25 by 50 mm (1.0 by 2.0 in.)will not necessarily give the same value as 25 by 25-mm (1.0 by 1.0-in.)faces. For many materials, the former are preferable because of the largergripping area which tends to reduce slippage. While both sizes of grippingsurface are permitted, the f

33、ace sizes used must be the same for all samplesin the test and must be recorded in the report.Metric Equivalentsin. 1 2mm 25 50FIG. 1 Schematic Illustration of Jaw Faces for Modified Grab TestD50340826.2.2 For modified grab tests, the top (or front) jaw facesshall measure 25 by 50 mm (1.0 by 2.0 in.

34、) or more, with thelonger dimension parallel to the direction of load application.The bottom (or back) jaw faces shall measure 50 by 50 mm(2.0 by 2.0 in.) or more. (See Fig. 1.)6.3 Metal Clamp, auxiliary, 170 g (6 oz) with at least100-mm (4.0-in.) width anvils.6.4 Distilled Water, for wet testing.6.

35、5 Nonionic Wetting Agent, for wet testing.6.6 Container, for wetting out specimens.6.7 Standard Fabrics4, for use in verification of apparatus.(See Annex A1.)6.8 Pins, stainless-steel, 10-mm (38-in.) diameter by 125mm (5 in.) long. Two are required if used.7. Sampling7.1 Lot SampleTake a lot sample

36、as directed in theapplicable material specification. In the absence of such aspecification, randomly take rolls or pieces that constitute thelot sample using the following schedule:Number of Rolls, Pieces in Lot,InclusiveNumber of Rolls or Pieces in LotSample1to3 all4to24 425 to 50 5over 50 10 % to

37、a maximum of 10 rolls orpiecesNOTE 3An adequate specification or other agreement between thepurchaser and the supplier requires taking into account the variabilitybetween rolls of fabric and between specimens from a swatch from a rollof fabric to provide a sampling plan with a meaningful producers r

38、isk,consumers risk, acceptable quality level, and limiting quality level.7.2 Laboratory SampleFrom each roll or piece of fabrictaken from the lot sample, cut at least one laboratory samplethe full width of the fabric and1m(1yd)along the selvage(machine direction).NOTE 4Results obtained on small hand

39、 samples (swatches) can onlybe considered as representative of the sample swatch and cannot beassumed to be representative of the fabric piece from which the handsample (swatch) was taken.7.3 Test SpecimensFrom each laboratory sample, take fivespecimens from the warp (machine) direction and eight sp

40、eci-mens from the filling (cross) direction (if tested) for eachtesting condition.7.3.1 Testing conditions include the following:7.3.1.1 Warp or Machine DirectionStandard conditionsfor testing textiles.7.3.1.2 Warp or Machine DirectionWet at 21C (70F).7.3.1.3 Filling or Cross DirectionStandard condi

41、tions fortesting textiles.7.3.1.4 Filling or Cross DirectionWet at 21C (70F).7.3.2 When using the constant-time-to-break technique andunfamiliar fabrics, prepare two or three extra specimens toestablish the proper rate of loading (or speed for testing).8. Conditioning8.1 For Conditioned Testing:8.1.

42、1 If the samples have a higher moisture content than themoisture present when at equilibrium in the standard atmo-sphere for testing textiles, precondition as directed in PracticeD 1776.8.1.2 Bring samples to moisture equilibrium in the standardatmosphere for testing textiles as directed in Practice

43、 D 1776.Equilibrium is considered to have been reached when theincrease in mass of the specimen in successive weighings madeat intervals of not less than 2 h does not exceed 0.1 % of themass of the specimen.NOTE 5It is recognized that in practice, materials are frequently notweighed to determine whe

44、n moisture equilibrium has been reached. Whileconditioning for a fixed time cannot be accepted in cases of dispute, it maybe sufficient in routine testing to expose the material to the standardatmosphere for testing textiles for a reasonable period of time before thespecimens are tested. As a guide

45、the following conditioning periods aresuggested:FiberMinimum Condi-tioning Period, h4Animal Fibers (for example, wool, and regenerated proteins) 8Vegetable Fibers (for example, cotton) 6Viscose 8Acetate 4Fibers having a regain less than 5 % at 65 % relativehumidity28.2 For Wet Testing:8.2.1 Specimen

46、s to be tested in the wet condition shall beimmersed in water at room temperature until thoroughly wetted(Note 6). To thoroughly wet a specimen, it may be necessary toadd not more than 0.05 % of a nonionic wetting agent to thewater. A test of any wet specimen shall be completed withintwo minutes aft

47、er its removal from the water.NOTE 6The material has been thoroughly wet out when it has beendetermined that additional immersion time does not produce any addi-tional changes in breaking strength of test specimens. This method ofdetermination must be used in cases of dispute. However, for routinete

48、sting in the laboratory, it may be sufficient to immerse the material for1h.8.2.2 The procedures in this test method should be used withcaution when testing fabrics that do not wet out uniformly andthoroughly because of the presence of sizing, oil, protectivecoatings, or water repellents.8.2.3 When

49、the strength of wet specimens without sizing,water repellents, etc. is required, before preparing the testspecimens, treat the material as directed in Test MethodsD 629, using appropriate de-sizing or finish removal proce-dures that will not affect the normal physical properties of thefabric.9. Preparation of Specimens9.1 General:9.1.1 Cut specimens with their long dimensions paralleleither to the warp (machine) direction or to the filling (cross)direction, or cut specimens for testing both directions if4Apparatus and accessories are commercially available