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TM_F_1804_
_08_2012
Designation:F180408(Reapproved 2012)Standard Practice forDetermining Allowable Tensile Load for Polyethylene(PE)Gas Pipe During Pull-In Installation1This standard is issued under the fixed designation F1804;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.Scope1.1 This practice provides a means to determine an allow-able tensile load(ATL)value for a polyethylene gas pipe thatis to be installed underground using methods that pull the pipeinto a trench(cut or plowed),bore hole,casing pipe,or the like.The ATL value takes into account pipe size,tensile yeildstrength,pipe temperature,and pulling load duration.1.2 The ATL is used to set the break-away strength for a“weak-link”device,or as a limit setting for other devices thatcontrol the maximum pulling force exerted by equipment usedto pull polyethylene gas pipe into an underground location,orto determine if pulling equipment can extert pulling forcegreater than the ATL value for the gas pipe being installed.Aweak-link device is installed where the pipe pulling equipmentis connected to the polyethylene gas pipe.If pulling loadexceeds the ATL limit,the device de-couples the pipe from thepulling equipment.Other measures or equipment that limit thepulling force on the pipe are also used.When the ATL value iscompared to the pulling force developed by the pull-in instal-lation equipment and equipment cannot extert pulling forcegreater than the ATL value,a weak-link or other device forlimiting the pulling force is not necessary.1.3 This practice does not address weak-link device designor requirements,nor does it address the design or requirementsfor other equipment or procedures used to limit the pullingforce applied to polyethylene gas pipe during pull-in installa-tion.1.4 This practice does not address installation methods orprocedures employed for pull-in of polyethylene gas pipe.1.5 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.1.6 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:2D638 Test Method for Tensile Properties of PlasticsD1600 Terminology forAbbreviated Terms Relating to Plas-ticsD2513 Specification for Polyethylene(PE)Gas PressurePipe,Tubing,and FittingsF412 Terminology Relating to Plastic Piping Systems3.Terminology3.1 Unless otherwise indicated,abbreviations are in accor-dance with Terminology D1600,and terms are in accordancewith Terminology F412.3.2 allowable tensile load(ATL),nThe maximum tensileload applied to a polyethylene gas pipe during pull-in instal-lation that does not result in an unrecoverable tensile elonga-tion of the pipe.NOTE1Polyethylene gas pipe materials are visco-elastic,that is,theyexhibit properties associated with both elastic materials such as rubber,and viscous materials such as wax or clay.When subjected to a tensileload that is significant,but less than the yield strength,polyethylene willelongate or stretch.If the load is then removed,polyethylene will,overtime,recover all or part of the elongation,depending upon the magnitudeof the load,and the length of time the load was applied.For the purposesof this practice,elongation that is not completely recovered in about 24 hafter the load is released,is considered unrecoverable.4.Significance and Use4.1 The ATL value is used to set the break-away strength ofa weak-link device,or to set other equipment used to limitpulling force during pull-in installation of polyethylene gaspipe,or to determine if pulling equipment can extert pullingforce greater than the ATL value for the polyethylene gas pipebeing installed.1This practice is under the jurisdiction of Committee F17 on Plastic PipingSystems and is the direct responsibility of Subcommittee F17.60 on Gas.Current edition approved Aug.1,2012.Published October 2012.Originallyapproved in 1997.Last previous edition approved in 2008 as F180408.DOI:10.1520/F1804-08R12.2For 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 4.2 The ATL value is determined before gas pipe installa-tion.5.Procedure5.1 The following information about the polyethylene gaspipe is required:size(outside diameter