ASTM_D_4032_-_08_2016.pdf

Designation:D403208(Reapproved 2016)Standard Test Method forStiffness of Fabric by the Circular Bend Procedure1This standard is issued under the fixed designation D4032;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last 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 determination of the stiff-ness of fabrics by the circular bend procedure.1.2 This test method is generally applicable to all types offabrics,including woven,knitted and nonwovens,of any fibercontent.NOTE1For other methods of testing for stiffness,refer to TestMethods D1388.1.3 The values stated in SI units are to be considered asstandard;the values in inch-pound units are included forinformation only.1.4 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 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:2D123 Terminology Relating to TextilesD1388 Test Method for Stiffness of FabricsD1776/D1776M Practice for Conditioning and Testing Tex-tilesD4850 Terminology Relating to Fabrics and Fabric TestMethods3.Terminology3.1 For all terminology relating to D13.60,Fabric TestMethods,Specific,refer to Terminology D4850.3.1.1 The following terms are relevant to this standard:circular bend,stiffness.3.2 For all other terminology related to textiles,see Termi-nology D123.4.Summary of Test Method4.1 A plunger forces a flat,folded swatch of fabric throughan orifice in a platform.The maximum force required to pushthe fabric through the orifice is an indication of the fabricstiffness(resistance to bending).5.Significance and Use5.1 Test Method D4032 for testing stiffness of fabrics isconsidered satisfactory for quality control testing.It may alsobe used for acceptance testing of commercial shipments sincethe test method has been used extensively in the trade field.Incases of differences in values reported by purchaser and sellerusing Test Method D4032 for acceptance testing,the statisticalbias,if any,between the laboratories of the purchaser and theseller should be determined with each comparison being basedon the testing of specimens taken homogeneously from a lot ofmaterial of the type being evaluated.Specimens should berandomly assigned in equal numbers to each of the laborato-ries.5.2 The circular bend procedure gives a force value relatedto fabric stiffness,simultaneously averaging stiffness in alldirections.The stiffness tests in Test Methods D1388 are of thesingle directional type.5.3 The circular bend procedure is simple to perform andmay be used for knitted,woven,or nonwoven fabrics,providedgage capacity is in keeping with fabric range tested.6.Apparatus6.1 Circular Bend Stiffness Tester,3(Figs.1 and 2),havingthe following parts:6.1.1 Platform,102 by 102 by 6 mm(4 by 4 by14in.)smooth-polished chrome-plated steel plate with a 38.1-mm(1.50-in.)diameter orifice.The lap edge of the orifice should beat a 45 angle to a depth of 4.8 mm(316in.)(see Fig.3).6.1.2 Plunger,25.4-mm(1.00-in.)diameter,mounted con-centric with orifice,6.4 mm(0.25 in.)clearance on all sides.The bottom of the plunger should be set at 3 mm(18in.)abovethe top of the orifice plate.From this position,the downwardstroke length is 57 mm(214in.).6.1.3 Force-Measurement Gage,dial or digital type(see9.3).1This test method is under the jurisdiction ofASTM Committee D13 on Textilesand is the direct responsibility of Subcommittee D13.60 on Fabric Test Methods,Specific.Current edition approved July 1,2016.Published July 2016.Originally approvedin 1981.Last previous edition approved in 2012 as D4032 08(2012).DOI:10.1520/D4032-08R16.2For 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.3Apparatus is commercially available.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 6.1.3.1 Dial gages with maximum reading pointer in differ-ent capacities ranging from 1 to 50 lbf,0.5 to 25 kgf,or 5 to200 N with 100 graduations minimum;or6.1.3.2 Digital gage with maximum reading“hold”featureand capacity of 100 lbf,50 kgf,or 500 N,with 1000graduations minimum.6.1.4 Actuator,manual or pneumatic.6.2 Specimen Marking Template,(102 by 204 mm)4.0 by8.0 in.6.3 Stop Watch,for checking stroke speed.7.Sampling7.1 Lot SizeFor sampling purposes,a lot is defined as asingle shipment of a single style of fabric.A lot may constituteall or part of a single customer order.7.2 Lot SampleAs a lot sample for acceptance testing;take at random the number of ro