ASTM_D_2221_-_01_2015.pdf

Designation:D222101(Reapproved 2015)Standard Test Method forCreep Properties of Package Cushioning Materials1This standard is issued under the fixed designation D2221;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.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 creepproperties of package cushioning materials.It is applicable tomaterials available in bulk,sheet,or molded form used for thecushioning of articles during storage,handling,and shipment.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 determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D4332 Practice for Conditioning Containers,Packages,orPackaging Components for TestingE105 Practice for Probability Sampling of MaterialsE122 Practice for Calculating Sample Size to Estimate,WithSpecified Precision,the Average for a Characteristic of aLot or Process3.Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 creepthe deformation of a material occurring withtime and due to an externally applied constant stress.Forcushioning materials specifically,it may be defined as thechange in thickness of a cushion under static compressive loadover a period of time.3.1.2 permanent setthe permanent change in thickness ofan unloaded cushion as a result of an applied compressive loadfor any given time interval and any given unloaded recoverytime period.4.Summary of Test Method4.1 The test apparatus consists of a suitable testing devicehaving a base plate and a guided movable platen which can beloaded with weights.The loaded movable platen is placed on acushion to simulate static compressive loading of cushioningmaterial in actual packaging.By measuring the change inthickness of the loaded cushion with time,creep properties ofthe cushioning material can be obtained.5.Significance and Use5.1 This test method determines the extent and nature ofcushion thickness change under static load.Creep data ob-tained by this test method are applicable to the cushion underthe conditions of the particular test and are not necessarily thesame as obtained in a complete pack in actual packagingenvironments.Data may be affected by magnitude of staticload,specimen area,shape,and thickness,by varying ambientconditions of temperature,humidity,by friction in the movableplaten guide system,and by actual cushion thickness.Vibrationin the vicinity of the test fixtures may also influence dataresults.6.Apparatus6.1 Movable,Guided Platen,capable of being weighted toachieve the desired loading along with a base to support thesample throughout the duration of the test.Two such assem-blies are shown in Fig.1 and Fig.2.6.2 Static Load Box Fixture(Fig.1),consisting of a mov-able guided platen and an outer box that shall act as the guideand the base plate for supporting the sample.6.2.1 Base Plate(Outer Box),may be constructed of34in.(19.0 mm)minimum white pine and fabricated to reduceswelling which may occur at high humidity.Aflat rigid plate ofappropriate dimensions is placed on the inside bottom surfaceand used as the base plate.The plate can be made of a materialsuch as aluminum,steel,rigid plastic sheeting or glass.6.2.2 Movable Guided Platen(Inner Box),may be loadedwith weights(for example,lead shot or molded lead weights),1This test method is under the jurisdiction of ASTM Committee D10 onPackaging and is the direct responsibility of Subcommittee D10.13 on InteriorPackaging.Current edition approved April 1,2015.Published May 2015.Originallyapproved in 1963.Last previous edition approved in 2010 as D2221 01(2010).DOI:10.1520/D222101R15.2For 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 and fabricated in the same manner as described in 6.2.1.A flatrigid plate similar to that described in 6.2.1 is placed betweenthe top of the test specimen and the movable platen and servesas a reference for measuring the height of the specimen.6.2.3 Two means of measurement,two position and fourposition,may be utilized.Amicrometer or steel rule capable ofmea