ASTM_D_2659_-_16.pdf

Designation:D265916Standard Test Method forColumn Crush Properties of Blown ThermoplasticContainers1This standard is issued under the fixed designation D2659;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.1.Scope*1.1 This test method covers the determination of mechanicalproperties of blown thermoplastic containers,whether blowncommercially or in the laboratory,loaded under columnarcrush conditions at a constant rate of compressive deflection.NOTE1Although this test method was developed specifically forblow-molded containers,the general procedure can also be applied tocontainers of suitable geometries produced by other means,for example,thermoforming,injection molding,etc.1.2 The values stated in SI units are to be regarded as thestandard.NOTE2There is no known ISO equivalent to this 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:2D618 Practice for Conditioning Plastics for TestingD883 Terminology Relating to PlasticsD4976 Specification for Polyethylene Plastics Molding andExtrusion MaterialsE4 Practices for Force Verification of Testing MachinesE83 Practice for Verification and Classification of Exten-someter Systems3.Terminology3.1 DefinitionsFor definitions of terms used in this testmethod and associated with plastics issues refer to the termi-nology contained in ASTM D883.3.2 Definitions of Terms Specific to This Standard:3.2.1 apparent crushing stiffnessthe ratio of the crushingload to the corresponding deflection at a point on the linearportion of the crushing load deflection curve(expressed innewtons per metre(or pounds per inch).3.2.2 columna compression member that is axially loaded.3.2.3 crushing load at failurethe crushing load applied toa blown thermoplastic container that produces a failure byfracture or parting of the material in any portion of saidcontainer(expressed in kilograms(or pounds).3.2.4 crushing yield loadthe first load at which an in-crease of deflection occurs with no increase in load in acompressive crushing test(expressed in units of kilograms(orpounds)of load).NOTE3In some cases,usually as a result of design or styling features,or both,of a specific container,multiple values of the crushing yield loadare be observed,that is,a small deflection occurs with no increase or witha decrease in the crush load,followed by resumption of the normal crushload change with deflection.This phenomenon cannot be ignored in theevaluation of the column crush properties of a blown thermoplasticcontainer,since it can be a very useful designated failure point for theapplication under consideration.The load at which this abrupt changeoccurs can be chosen as a crushing yield load for study.In such a case,thereport of results should be accompanied by a proper description of thecrushing yield load selected.3.2.5 deflection at crushing yield loadthe decrease inlength of the container specimen produced at the crushing yieldload along the center line of testing(axis of crushing,see Fig.1)(expressed in millimetres(or inches).3.2.6 gage lengththe original length of that portion of thespecimen over which strain or change in length is determined.4.Significance and Use4.1 Column crush tests only provide information about thecrush properties of blown thermoplastic containers whenemployed under conditions approximating those under whichthe tests are conducted.4.2 The column crush properties include the crushing yieldload,deflection at crushing yield load,crushing load at failure,and apparent crushing stiffness.Blown thermoplastic contain-ers made from materials that possess a low order of ductilitycan fail in crushing by brittle fracture.In such cases,the1This test method is under the jurisdiction of ASTM Committee D20 on Plasticsand is the direct responsibility of Subcommittee D20.19 on Film,Sheeting,andMolded Products.Current edition approved May 1,2016.Published May 2016.Originallyapproved in 1967.Last previous edition approved in 2011 as D2659-11.DOI:10.1520/D2659-16.2For 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.*A Summary of Changes section appears at the end of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 crushing yield load is equivalent to the crushing load at failure.Blown thermoplastic containers made of ductile materials