ASTM_D_5342_-_97_2002.pdf

Designation:D 5342 97(Reapproved 2002)An American National StandardStandard Test Method forResistance to Bending of Paper and Paperboard(Taber-Type Tester in Basic Configuration)1This standard is issued under the fixed designation D 5342;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 test method covers a procedure used to measure theresistance to bending of paper and paperboard.1.2 The bending moment required to deflect the free end ofa 38-mm(1.5-in.)wide vertically clamped specimen 15 fromits center line when the load is applied 50 mm(1.97 in.)awayfrom the clamp is determined.The resistance to bending iscalculated from the bending moment.1.3 Some instruments of the type described in this testmethod(see Section 6)may be equipped with ultrasensitiveattachments or may be modified to accommodate shorterspecimen lengths than that specified in this test method(seeSection 9).1.4 Test Method D 5650 describes a modification of theinstrument described in this test method for measurements inthe 0 to 10 Taber stiffness range only,and which requires asmaller test specimen.The modified procedure may be recom-mended for papers which are low in grammage or highlyflexible,or both.1.5 Test results obtained using modifications of the basicTaber-type instrument such as that described in Test MethodD 5650 have been reported to be as much as 40%differentfrom those obtained using this test method,and such modifi-cations must not be used when this test method is specified.1.6 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:D 585 Practice for Sampling and Accepting a Single Lotof Paper,Paperboard,Fiberboard,or Related Products2D 685 Practice for Conditioning Paper and Paper Productsfor Testing2D 1968 Terminology Relating to Paper and Paper Products2D 5650 Test Method for Resistance to Bending of Paperof Low Bending Stiffness(Taber-Type Tester in the 0 to 10Taber Stiffness Unit Configuration)2E 122 Practice for Calculating Sample Size to Estimate,with a Specified Tolerable Error,the Average for Charac-teristic of a Lot or Process33.Terminology3.1 DefinitionsDefinitions shall be in accordance withTerminology D 1968 and the Dictionary of Paper.44.Summary of Test Method4.1 A test specimen of defined dimensions is bent through aspecified angle using a specific testing instrument.The result-ing bending moment is read from the instrument scale.4.2 The resistance to bending can be calculated from thebending moment.5.Significance and Use5.1 Bending resistance of paper relates to a number ofend-use applications including wrapping,printing,copy ma-chine performance,high-speed mechanical handling of docu-ments,and other applications.6.Apparatus6.1 Description:6.1.1 The basic instrument that has been used for the testdescribed in this test method for nearly fifty years is a manuallyoperated(crank-driven)instrument.Over the years,variousimprovements in the basic instrument have been made forimproved ease of use or greater reproducibility of data,or both.These improvements include replacement of the manual(crank)drive system with a constant speed motor,addition ofautomatic data determination,and automated instrument(mo-tor sequencing)operation.Fig.1 shows the motor-drivenversion of the instrument(see 6.1.2).It is the motor-drivenmodel of the basic instrument that is the basis for this testmethod.However,any of the instrument variations described1This test method is under the jurisdiction of ASTM Committee D06 on Paperand Paper Products and is the direct responsibility of Subcommittee D06.92 on TestMethods.Current edition approved Dec.10,1997.Published November 1998.Originallyapproved in 1993.Last previous edition approved in 1995 as D 5342 95.2Annual Book of ASTM Standards,Vol 15.09.3Annual Book of ASTM Standards,Vol 14.02.4Available from the Technical Association of the Pulp and Paper Industry,P.O.Box 105113,Atlanta,GA 30348.1Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959,United States.in this section,when properly calibrated and operated,shouldyield the same result.The components of the basic instrumentcan be seen in Fig.1 as follows:6.1.1.1 A pendulum(A)supported in antifriction in bear-ings,carrying a vise(C)that has two clamping screws forholding and centering the test specimen,the lower edge of thevise coinciding with the center of the pendulum bearing.Thependulum is balanced,and at its lower end is a stud(D)towhich weights may be attached and that loads the pendulum a