DacrometA490
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Transcript of DacrometA490
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LeJeuneBoltCompany DACROMETCOATEDA490BOLTS
www.lejeunebolt.comI3500WestHighway13,Burnsville,MN55337I800.872.2658
Burnsville,MNASTMA490StructuralBoltshavehistoricallybeen limited toplain finishdue to thepotential for hydrogen embrittlement during coating using industry standard processes, namely zinccoating mechanically deposited per ASTM B695 and/or Hot Dip perASTM A153. In 2008, ASTM approved the use of zinc/aluminumprotective coatings perASTM F1136 for use onA490 structural bolts.The most common of these coatings is sold under the trade nameDacromet, produced byMetal Coatings International and applied bycertifiedapplicators.ThiscoatingwillrevolutionizethemarketforA490boltsandprovide foramuchneededhigh strength structural fastenerwithaprotectivefinish.
While ASTM tested and approved the coating, many issues remained for its practical use in themarketplace. Questions relating to Dacromet grade and sealer combination and their relation todesiredkfactor,nutovertapandrotationalcapacitytestingviabilityhavegoneessentiallyunanswered.
Untilnow.
Two recent projects specifying Dacromet coated A490swereawardedtoLeJeuneBoltCompany.
The firstmajor project awardedwas the SAS Span for thenewSanFranciscoOaklandBayBridge.Thisprojectwasthefirst, and certainly the largest, to specify A490 bolts withDacromet coating. Nearly two yearsof research,productdevelopment, testing, and production has given LeJeuneunparalleledexperiencethatonlyaprojectofthismagnitudecan offer. The bridge designer specified A490M (metric)boltswithDacromet.ThemetricA490isnotnormallyusedintheUnitedStatessotherewasnoavailablestock.Further,therewasno toolingor rawmaterial at themanufacturinglevel to produce these bolts. Finally, this quantity ofstructuralgradefastenershadneverbeenprocessedthroughanyofthelicensedDacrometapplicators.Thatswherewecamein.LeJeunewasthecatalyst,bringingtogetherleadingmanufacturersinthefastenerindustrytoaskandanswerthemany questions needed to supply the contractor with
reliable,consistent fasteners. Throughourextensive researchanddevelopmentstages,we identifiedtheoptimumcombinationofcoatinggrade,sealer,andnutovertapthatprovidedthemostconsistentkfactor.OurstudyshowedthatusingDacromet320grade3withPlusSealerontheboltandDacromet320grade5withPlusSealeronthenutwithanovertapof.018andDacromet320grade3PlusSealeronthewasherprovidedconsistentkfactorresultsintheoptimalrange.FortheDacrometapplication,
SelfAnchoredSuspensionSpan(SAS)SanFranciscoOaklandBayBridge
Oakland,California
AmericanBridgeFluorJV
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LeJeuneBoltCompany DACROMETCOATEDA490BOLTS
www.lejeunebolt.comI3500WestHighway13,Burnsville,MN55337I800.872.2658
wechosetheracksprayprocessfortheboltsandthedipspinmethodforthenutsandwashers. Thiscombination of processes provided for the most favorable combination of coating quality andconsistencywhileadheringtothebudget.LeJeuneBoltCompanyworkedwithABFJVtoevaluateandwriterotationalcapacityparametersthatdidnotexistfortheA490MboltwithDacromet.Thesetestprocedureshavebeenimplementedandarecurrentlyinuseonthisproject.Finally,weemployedfourmanufacturing sourcesand twoDacrometapplicators toproduce the finishedmaterial. We startedwith an extensive audit and qualification process for each manufacturer. Once these audits wereapprovedby thecontractor,wemovedon to toolingdesignandmanufacturing. Once toolingwas inplace and rawmaterialprocured,manufacturing began in earnest tomeet the rigorous criticalpathdeadlines. Material was received and processed according to our ISO based quality program.Rotational Capacity Testingwas performed in our lab and thematerialwas certified. A CALTRANScertified inspectorwascalled in to samplematerial tobe sent to theMETSLab foranother roundoftesting and approval. Once this was complete, CALTRANSdispatched their inspector to our facility to tag and certifythe approvedmaterial for release. LeJeune thenpackagedmaterial according to the project release schedule andshipped to the final destinations; shop bolts to thefabrication facility located inShanghai,Chinaand fieldboltsto theOakland,California jobsite. Whatdoes twoyearsofresearch, development, testing, production, and inspectionundertherigorousscrutinyofAmericanBridgeFlourJVandCALTRANS for the largest construction project in CaliforniahistorymeanEVERYTHING!
ForDuroFelguera,We tookwhatwe learned fromour twoyears of preparation on the SAS Bay Bridge Project anddelivered to them technical data and research unavailableanywhereelseintheindustry.Thecontractorconsultedwithusextensively throughout thebidstage. Whilewecouldntalways tell themwhat theywanted tohear,wealways toldthemwhattheyneededtohear.Well,theychoseLeJeune.Wewerenotthecheapest,ortheclosesttoacoastalportcity.Whatwewerewasthemostinformedofthebunchandwewerewillingtoshareourinformationbeforewewonthecontract.Ourphilosophyofprovidingvaluetotheindustry,nomattertheoutcome,serveduswellonthisproject.Letusdothesameforyouonyournextproject.
IronOreConcentratorBuildings
Venezuela
DuroFelgueraPlantasIndusriales
