ASTM_D_5649_-_15.pdf

Designation:D564915Standard Test Method forTorque Strength of Adhesives Used on Threaded Fasteners1This standard is issued under the fixed designation D5649;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 test method is used to make comparative assess-ments of the securing or locking effect of adhesives used inthreaded assemblies.1.2 The values stated in inch-pound units are to be regardedas standard.No other units of measurement are included in thisstandard.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:2D907 Terminology of AdhesivesD2651 Guide for Preparation of Metal Surfaces forAdhesiveBondingE177 Practice for Use of the Terms Precision and Bias inASTM Test MethodsE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method3.Terminology3.1 DefinitionsFortechnicaltermspertainingtoadhesives,see Terminology D907.3.2 Definitions of Terms Specific to This Standard:3.2.1 breakaway torque,nthe initial torque required tobreak the bond measured at the first movement between the nutand the bolt when unscrewing an unseated assembly.3.2.2 on torque,nthe maximum torque required to screwthe nut onto a preapplied adhesive-coated bolt.3.2.3 prevailing torque,nthe torque measured after theinitial breakage of the bond measured at 180 rotation of thenut.4.Summary of Test Method4.1 This test method consists of determining the torquerequired to unscrew a bonded nut and bolt assembly.Break-away torque and prevailing torque are determined.5.Significance and Use5.1 This test method provides reasonably accurate informa-tion with regard to the determination of the securing or lockingeffect of adhesives used in threaded fasteners.This test methodmay also be used to determine the degree of cure and the effectof environment on torque strength.5.2 The accuracy of the test results depends to a largedegree on the thread clearance of the test fasteners and theinclusion of air bubbles in the bond line.Data generated by thistest method should be safety-factored accordingly if used asquality assurance acceptance or rejection.6.Apparatus6.1 Electronic RecordingTest machine consisting of aclamping device to secure the bolt head,and a device forturning the nut with simultaneous measurement and registra-tion of the torque as a function of the angle of turning by directanalog or digital means.6.2 Direct ReadingA clamping device to secure the headof the bolt,and a torque wrench accurate to 65%.7.Test Specimens7.1 Any size and substrate fasteners may be used uponagreement between the supplier and the user of adhesives.7.2 Unless otherwise agreed upon between the user and theadhesive manufacturer,degrease all non-plated nuts and bolts(refer to Guide D2651),store in an atmosphere of lowhumidity,and keep them clean.7.3 Where desired,and if agreed upon between the user andthe adhesive manufacturer,non-plated nuts and bolts may beused as received,reoiled,or after other special treatments.7.4 Plated nuts and bolts do not normally require any specialcleaning prior to assembly.1This test method is under the jurisdiction of ASTM Committee D14 onAdhesives and is the direct responsibility of Subcommittee D14.60 on AdhesiveMaterial Classification System.Current edition approved April 1,2015.Published April 2015.Originallyapproved in 1994.Last previous edition approved in 2008 as D5649 01(2008).DOI:10.1520/D5649-15.2For 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 8.Assembly8.1 Assemble not less than five specimens for each test asfollows:8.1.1Preassemble nuts and bolts prior to application ofadhesive.Discard any pairs showing sticking due to burrs ordamaged threads.Disassemble the parts.8.1.2 For liquid adhesives,apply sufficient adhesive to thebolt to completely cover an area equal to the height of the nutplus three threads.Also,apply adhesive to the threads of thenut.Follow the adhesives manufacturers instructions forapplication of preapplied adhesives.8.1.3 Remove,flip and re-screw the nut onto the bolt byhand,allowing three threads to protrude.For preappliedadhesives,screw the nut onto the coated bolt using theapparatus in 6.1 or 6.2 and record the on torque.Allow threeadhesive-coated threads to protrud