ASTM_F_137_-_08_2013.pdf

Designation:F13708(Reapproved 2013)Standard Test Method forFlexibility of Resilient Flooring Materials with CylindricalMandrel Apparatus1This standard is issued under the fixed designation F137;the number immediately following the designation indicates the year of originaladoption or,in the case of revision,the year of last revision.Anumber in parentheses indicates the year of last reapproval.Asuperscriptepsilon()indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S.Department of Defense.1.Scope1.1 This test method covers the determination of the flex-ibility of resilient flooring materials by means of cylindricalmandrel apparatus.It is especially applicable to sheet goodsand some tiles.1.2 The values stated in inch-pound units are to be regardedas standard.The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.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 standard to establish appro-priate safety and health practices and to determine theapplicability of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2E691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test MethodF141 Terminology Relating to Resilient Floor Coverings3.Terminology3.1 For definitions,refer to Terminology F141.4.Significance and Use4.1 Flexibility is that property of a material which allows itto be deformed by bending or rolling without cracking,breaking,or other permanent defects,using whatever force isnecessary to bend or roll it.Flexibility is an importantcharacteristic of flooring in that it provides for ease of handlingin rolling,cutting,and fitting.5.Apparatus5.1 Flexibility Test Equipment,consisting of mandrels,thatis,cylindrical rods with circular cross sections having outsidediameters of 0.25 in.(6.4 mm)and 0.50 to 5 in.(12.7 to 127mm)increasing in increments of 0.5 in.(12.7 mm).Thecontacting faces of the rods shall be a minimum of 2.5 in.(63.5mm)in length.5.2 Stand or Other Device,to firmly support the mandrel ina horizontal position during the test.5.3 Conditioning Area,capable of maintaining 73.4 6 1.8F(23 6 1C)and 50 6 5%relative humidity.5.4 Die,Knife,or Similar Instrument to prepare test speci-mens with uniform smooth edges.6.Test Specimen6.1 The test specimens shall consist of a portion of thematerial 2 6 0.05 in.(50 6 1.27 mm)wide and at least 9 in.(225 mm)long.6.2 Use a die,knife,or other similar instrument to preparethe specimen and to produce uniform smooth edges.Do nottest specimens with nicked or fractured edges.7.Conditioning7.1 Condition the test specimens for at least 24 h at 73.4 61.8F(23 6 1C)and 50 6 5%relative humidity,and test inthe same environment.Alternatively,testing may be performedat room temperature in an uncontrolled environment if carriedout within 5 min.7.2 Specimens shall be conditioned on a flat surface.Ifnecessary,they can be weighted to remove all curvature.8.Procedure8.1 In the actual flexing of the specimen,place the specimenover a mandrel with the wearing surface face out and the majoraxis of the specimen perpendicular to the major axis of themandrel.8.2 Bend the material around the mandrel at a uniform ratethrough a 180 angle while holding the specimen at each end.1This test method is under the jurisdiction ofASTM Committee F06 on ResilientFloor Coverings and is the direct responsibility of Subcommittee F06.20 on TestMethods-Products Construction/Materials.Current edition approved Dec.1,2013.Published January 2014.Originallyapproved in 1971.Last previous edition approved in 2008 as F137-08.DOI:10.1520/F0137-08R13.2For 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.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 Take 3 to 5 s to complete the bend.Maintain a good contactbetween specimen and mandrel.8.3 Examine the specimen face visually in the bent positionfor breaks,cracks,or other damage at the completion of thebending operation.When required by the detailed specification,straighten the specimen at the same rate at which it was bentand examine the back for the same faults.8.4 When a mandrel of particular diameter has beenspecified,as for a purchase specification,use that mandrel.8.5 Determine the smallest mandrel around which the ma-terial may be bent without showing breaks,cracks,or otherdamage.To do this,estimate the size of the mandrel over whichthe specimen will not break.Then use a series of mandrels,each one consecutively smaller than the first,until breaks orcracks are exhibited.Start with a fresh specimen for eachseparate flex.