ASTM_D_2529_-_74_scan.pdf

900927b O025974 bit7 X.I Designation:D 2529-74 4CTB Standard Test Method for BURSTING STRENGTH OF PAPERBOARD AND LINERBOARD This Standard is issued under the fixed designation D 2529:the number immediately following the designation indicates the year of original adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.1.scope 1.1 This method covers a procedure for measuring the bursting strength of paperboard,including linerboard,employing a disk-shaped,molded diaphragm-type instrument.NOTE I-For the bursting strength of paper,see ASTM Method D774,Test for Bursting Strength of Paper.3 For the bursting strength of corrugated and solid Fiberboard,see ASTM Method D2738,Test for Bursting Strength of Corrugated and Solid Fiberbard.2.Applicable Documents 2.1 ASTM Standards:D 585 Sampling and Accepting a Single Lot of Paper,Paperboard,Fiberboard,or Related Products D 641 Conditioning Paperboard,Fiber-board,and Paperboard Containers for Testing3 3.Summary of Method 3.1 A specimen of board is clamped be-tween two platens with circular openings in the center.An expansible diaphragm is dis-tended through the lower platen by means of hydraulic pressure until the specimen bursts.The maximum hydraulic pressure when which the specimen ruptures is recorded.4.Significance 4.1 The bursting strength test of paper-board,including linerboard,is a composite measure of certain properties of the sheet structure,principally tensile strength and elongation.In general,bursting strength is dependent on the type,proportion,prepara-tion,and amount of the fibers present in the sheet and on their formation,internal sizing,and to some degree,the surface treatment.While bursting strength is an empirical prop-erty,this test,in combination with basis weight,serves to define“standard grades”in com-merce.5.Apparatus 5.1 Bursting Tester,consisting of the fol-lowing:5.1.1 Means for clamping the test specimen between two annular,plane surfaces having fine concentric tool marks to minimize slip-page.The upper clamping platen(clamping ring)shall have a diameter of 3.75 in.(95 mm),a thickness of 0.375 in.(9.5 mm),and a circular opening 1.240+0.001 in.(31.50+0.02 mm)in diameter.The lower edge of the opening(side in contact with the board)shall have a 0.025-in.(0.64-mm)radius.The lower clamping surface(diaphragm plate)shall have a thickness of 0.219+0.003 in.,(5.56 i 0.08 mm)with an opening 1.240+0.001 in.(31.50+0.02 mm)in diameter.The upper edge of the opening(in contact with the board)shall have a 0.016-in.(0.4-mm)radius,and the lower edge of the opening(in contact with the rubber diaphragm)a radius of 0.125 in.(3.2 mm)to prevent cutting the rubber when pressure is applied.The upper clamping ring shall be connected to the clamping mechanism through a swivel joint to facilitate an even clamping pressure.The openings in the two clamping This method is under the jurisdiction of ASTM Com-mittee D-h on Paper and Paper Products.Curreiii edition approved Sept.27,1974.Published De-cem-r 1974.Originally published as D2529-66.Last previous edition D 2529-68.This methoa is related to IS0 Draft Recommendation DR2759,annual Book of ASTM Standards,Part 20.486.,:I.f,nsNOTICE:This standard has either been superseded and replaced by a new version or discontinued.Contact ASTM International(www.astm.org)for the latest information.900927b 0025975 553 plates shall be concentric to within 0.005 in.(0.13 mm)and their clamping faces shall be flat and parallel(see Al.l of Appendix AI).5.1.2 A molded(disk-shaped)diaphragm.requiring a pressure of not less than 23 nor more than 30 psi(210 kPa)to distend it to a height of 0.375 in.(9.5 mm)above the dia-phragm plate(see A1.2 of Appendix AI).5.1.3 Means of forcing liquid into the pres-sure chamber below the diaphragm at a steady rate of 170 15 ml/min(see A1.3 of Appen-dix AI).This pressure shall be generated by a motor-driven piston forcing a liquid(glycerin)into the pressure chamber of the apparatus.5.1.4 A pressure gage of the maximum-reading or the lazy-hand type.The scale should have a radius of 1%in.(50 mm),with graduations extending over a minimum arc of 270 deg indicating bursting pressure in psi,with an accuracy of/2%of full scale,and have sufficient capacity so that all readings can be maintained in the middle half of the scale.In its operating position have the gage inclined between horizontal and not over 30 deg from the horizontal.When more than one gage is mounted on a single apparatus,only the gage on which the measurement is being made shall be open to the hydraulic system so as not to reduce the rate of distension of the specimen.NOTE 2-Calibrate the gages frequently enough to ensure their accuracy(once a week if in constant use,or before using if they have been idle for a month or more).Calibrate the gages R hile inclined at the same angle as used during a test by means of a dead-weight gage tester.During calibration,apply the pressure so that the