ASTM_D_5251_-_98a_2003.pdf

Designation:D 5251 98a(Reapproved 2003)Standard Practice forthe Operation of the Tetrapod Walker Drum Tester1This standard is issued under the fixed designation D 5251;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(e)indicates an editorial change since the last revision or reapproval.1.Scope1.1 This practice describes the equipment and operation ofthe Tetrapod Walker for testing pile floor coverings with athickness of 20 mm(0.8 in.)or less because thicker materialsimpede proper operation of the tumbler.1.2 This practice is applicable for use in testing unused pilefloor covering of all types.It is not applicable for use in testingused pile floor covering.1.3 The values stated in either acceptable SI units or in otherunits shall be regarded separately as the standard.The valuesstated in each system may not be exact equivalents;therefore,each system must be used independently of the others,withoutcombining values in any way.In case of referee decisions,theSI units shall prevail.1.4 This practice does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this practice 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:D 123 Terminology Relating to Textiles2D 418 Methods of Testing Pile Yarn Floor Covering Con-struction2D 1776 Practice for Conditioning Textiles for Testing2D 5684 Terminology Relating to Pile Floor Coverings33.Terminology3.1 DefinitionsFor definitions of pile yarn floor coveringrelated terms used in this practice,refer to TerminologyD 5684.For definitions of other textile terms used in thispractice,refer to Terminology D 123.4.Summary of Practice4.1 The specimen is secured as the lining of a rotatabledrum with the pile surface exposed.A four legged metalcasting(tetrapod)8walks on the pile surface of the specimenas it is tumbled in the drum.The drum is rotated about itslongitudinal axis for a specified number of revolutions.5.Significance and Use5.1 This equipment may be used to bring about the changesin texture on the surface of pile floor covering caused bymechanical action.6.Apparatus,Material,and Reagent6.1 Tetrapod Tumbler Tester46.1.1 DrumConstructed of a rigid material and capped bya lid that is firmly secured.Each drum is equipped with twosprings to hold the test specimen in place during testing.Theinner dimensions of the drum are as follows:Diameter=2056 5 mm(8.0 6 0.2 in.)Height=1906 5 mm(7.6 6 0.2 in.)6.1.2 Tetrapod WalkerA metal casting,tetrahedral inshape,with four legs placed equidistant from one another.Forexample,the outermost points correspond to the points on anequilateral tetrahedron and the large angle between any twolegs is 2 rad(109.5).Each leg shall have a replaceable plasticfoot at the end.The free standing height of the tetrapod with 3of the 4 plastic feet in one plane is 125 6 2 mm(5 6 0.1 in.).The total mass of the tetrapod including the feet is 1000 6 2.5g(2.25 6 0.21 lb).The minimum hardness of the plastic feetsupplied by the manufacturer shall be 75 6 5 Type Adurometer.6.1.3 Driving SystemCradles a drum on rollers and keepsthe axis of the drum level,rotates at 5.2 6 0.2 rad/s(50 6 2rpm)and has a counter that can be preset to stop the drum afterany number of revolutions.Drive systems that do not reverseshall have the direction of rotation shown on the drum.6.2 Vacuum Cleaner,upright-type with beater bar.6.3 Solvent,either ethyl alcohol(CH3CH2CHOH),or iso-propyl alcohol,(CH3)2CHOH technical grade.1This practice is under the jurisdiction ofASTM Committee D13 on Textiles andis the direct responsibility of Subcommittee D13.21 on Pile Floor Coverings.Current edition approved April 10,1998.Published September 1998.Originallypublished as D 5251 92.Last previous edition D 5251 98.2Annual Book of ASTM Standards,Vol 07.01.3Annual Book of ASTM Standards,Vol 07.02.4Suitable apparatus is available from the Wira Instrumentation,3 Water Lane,Bradford BD1 2JL,England;Lawson Hemphill Sales,Inc.,P.O.Box 6388,Spartanburg,SC;Williams Asselin,Inc.,7774 Perras Blvd.,Montreal,Quebec,Canada H1E 5B2.1Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959,United States.7.Preparation of Specimen7.1 Marking the SpecimenBefore cutting out the testspecimen,mark on the secondary backing of each specimen thedirection of the pile lay and the direction of the tetrapod“walk”.7.2 Size of SpecimenCut the specimen approximately 610by 205 mm(24.0 by 8.0 in.).The long dimension shall beparallel to the lengthwise direction of the carpet.Take nospecimen within 100 mm(4 in.)of the trimmed selvage.8.Conditioning8.1 Bring the specimen to moisture equilibrium for testingin the standard atmosphere for testing textiles approa