ASTM_B_968_-_B_968M_-_16.pdf

Designation:B968/B968M16Standard Test Method forFlattening of Copper and Copper-Alloy Pipe and Tube1This standard is issued under the fixed designation B968/B968M;the number immediately following the designation indicates the yearof original adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.A superscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope*1.1 This test method establishes the requirements for theflattening test for copper and copper alloy pipe and tube of allsizes.The method addresses both inch-pound and metricconsiderations,and both seamless and welded product.1.2 UnitsThe values stated in either inch-pound units orSI units are to be regarded as standard.Within the text,SI unitsare shown in brackets.The values stated in each system maynot be exact equivalents;therefore,each system shall be usedindependently of the other.Combining values from the twosystems may result in non-conformance with the 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:2B153 Test Method for Expansion(Pin Test)of Copper andCopper-Alloy Pipe and TubingB846 Terminology for Copper and Copper Alloys3.Terminology3.1 For definitions of terms related to copper and copperalloys,refer to Terminology B846.4.Summary of Test Method4.1 The prepared test sample is flattened in a press to aspecified maximum thickness,and then inspected for defects ofa size and nature that would interfere with the intendedapplication of the product specification.5.Significance and Use5.1 When properly performed and interpreted,the flatteningtest will provide information about the relative ductility of atube and presence of surface defects.For welded tube products,the test will provide information on the integrity of the weldseam.5.2 In certain product specifications which establish require-ments for tubes of sizes greater than 4 in.100 mm,the testmay be allowed as a substitute to the expansion pin test in TestMethod B153.6.Apparatus6.1 Testing Machine(Press)Any type of testing machine;either hydraulically or mechanically operated,that will exertpressure sufficient to flatten the pipe or tube to the requireddegree.6.2 Micrometer CaliperAny measuring device that has thecapability to measure a flattened sample approximately three(3)times the product wall thickness.7.Sampling and Test Specimen Preparation7.1 For seamless product up to and including 4 in.100 mmoutside diameter:7.1.1 A test specimen shall be cut to a length that will allowthe tube to be flattened at three(3)places along the length,witheach flattened area to be at least 2 in.50 mm in length.Whenthe temper is other than annealed,the sample may be annealedprior to testing.7.2 For welded product up to and including 4 in.100 mmin outside diameter:7.2.1 A test specimen shall be cut to a length that will allowthe tube to be flattened along the length,so a total of at least12 in.305 mm is flattened.When the temper is other thanannealed,the sample is allowed to be annealed prior to testing.7.3 For seamless product over 4 in.100 mm in outsidediameter:7.3.1 A test specimen shall be cut to a length that will allowthe tube to be flattened once,with the flattened area to be atleast 4 in.100 mm in length.When the temper is other thanannealed,the sample is allowed to be annealed prior to testing.7.3.2 Both ends of the test specimen may be prepared byfiling or cutting to provide smooth end surfaces,free fromscratches or burrs which might interfere with the test.1This test method is under the jurisdiction of ASTM Committee B05 on Copperand Copper Alloys and is the direct responsibility of Subcommittee B05.06 onMethods of Test.Current edition approved April 1,2016.Published April 2016.Originallyapproved in 2009.Last previous edition approved in 2010 as B968/B968M 10.DOI:10.1520/B0968_B0968M-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 8.Procedure8.1 For seamless product up to and including 4 in.100 mmoutside diameter:8.1.1 Each test specimen shall be flattened in a press at three(3)places along the length,each new place to be rotated on itsaxis approximately one-third turn from the last flattened area.Each flattened area shall be at least 2 in.50 mm in length.Aflattened test specimen shall allow a micrometer caliper set atthree(3)times the wall thickness to pass fre