TECHNICALARTICLEFORPRODUCTIONRESOURCESCUSTOMERSIsyourmechanicalpowerpressOSHAcompliant?Ifyouusemechanicalpowerpressesinyouroperationitwillpayyoutoknowwhetheryourpressescomplywiththecodeoffederalregulationstitle29part1910.217.Failuretocomplycanresultinacostlyfine!1910.217isbrokenintoseveralsections.We’llpublishaseriesofarticlescoveringallthesectionswiththisfirstarticletreating1910.217(a)generalrequirementsand(b)guardingandconstruction,general.Thispieceisintendedtocoversignificantissuesnotnitpickingdetail.Theintentistoallowyoutoquicklygetanideawhetheryourmachinescomply.Elementstreatingfullrevolutionclutchpressesareignoredsincethistypeofmachineisrapidlyfallingoutofuse.Generally,ifyourpresswasdesignedandmadebyaUSbuilderonorafterJanuary1,1974it’slikelytobecompliantwithsections(a)and(b).Thismaynotbethecaseifundocumentedwiringchangeshavetakenplace.Additionally,you’llneedtopayattentionto(c)”safeguardingthepointofoperation”coveredinanotherarticle.AlsoyoushouldbeawareoftheindustryconsensusstandardANSIB11.1whichismoredemandingthanthecurrentOSHAstandard.SomefeelOSHAmayadoptthemorestringentprovisions(we’lltreatthedifferencesinOSHAandANSIinalaterarticle).�Thegeneralrequirementsof(a)requirethatanyonereconstructingormodifyingapressdosoinaccordancewiththestandard.�Excludedmachinesincludepressbrakes,hydraulicpresses,pneumaticpresses,hotmetalpresses,forgingpresses,hammers,andrivetingmachines.It’simportanttonoteherethatapressbrakeusedasapowerpressisconsideredapowerpress.�1910.217(b)treatsbrokenorfallingcomponents.Earlyonsomeemployersstartedtyingdownmotorsandanythingelseonthetopofthepress.Thisisreallynotnecessary;however,itisimportanttoinsurethatabrokenspringwillnotresultinbrakingfailure.1910.217(b)(7)treatspartrevolutionclutch(airclutch)pressesinsomedetail;requirementsfollow:�Aredemergencystopcontrolmustbeprovided.�Supervisorycontrolofthestrokemodeisrequired(keylockforoff,inch,single,andcontinuous).Notekeysshouldnotbeleftintheselectorswitch.�Inchmodehastopreventclutchengagementwhileonehandisinthepointofoperation.Thismeanstwohandinchorasingleinchbuttonlocatedagooddistancefromthetool.Positioningorthreadingmaterialwithonehandwhileinchingwithanotherisnotacceptable!�Concurrentoperationofthetwohandcontrolisrequired–youcan’ttieonebuttondown�Thetwohandcontrolmustkeepthehandsbusyduringthedownstroke–thisisnotatripdevice.�Operationsusingmorethanoneoperatormusthavecompleteoperatorstationsforeachperson.�MachinesrunintheContinuousorAutomaticmoderequiretheoperatortomakeapriorconsciousactbeforeengagingthismode–usuallythisrequirestheoperatorpushaprioractarmingswitchthenholdthetwohandcontrolthroughbottomdeadcenter.�Ifafootswitchisusedasupervisoryhand/footselectorisrequired(note:footswitchesarenotillegal;however,theydorequireappropriatepointofoperationsafeguardsordevices)�Dualvalvesarerequiredtopreventdecayinstoppingperformance.Technicallythisisnotrequiredonapressthatrunsonlycontinuous;however,ifalightcurtainisusedasthepointofoperationguardcommonsensedemandsadualvalve.�Airpressureswitchesorsensorsmonitoringtheclutchandthecounterbalancearerequired.Theobjectivehereistodetectalossinpressureandstopthemachinethenpreventautomaticrestartifpressurecomesbackup.�Lockableoffdisconnectswitchisrequired�Magneticmotorstartersrequired,manualstartersareunacceptable�Controltransformerwithfusedsecondarytoreducevoltagestocontrolcircuitsto120vacorless�Groundfaultdetectiondevice�Controlcircuitdesigntominimizethepossibilityofanunintendedstrokeintheeventofacontrolcomponentfailure.�Controlreliability–requiredforhandsindieoperationsthatusealightcurtain,twohandcontrol,ortypeBslidingbarrierdeviceasthepointofoperationsafeguard.Whenrequiredthecontrolcircuitmustinsurethatnormalstoppingactionwilloccurintheeventofasinglecomponentfailurebutpreventadditionalstrokinguntilthefailureiscorrected.Thisrequiresredundancyandcrosschecking.Ifyouhavehandsindieoperationsyoushouldcheckwithyourpressorcontrolmanufacturertoinsurethecontrolcomplieswiththissection.�Brakemonitoring-requiredforhandsindieoperationsthatusealightcurtain,twohandcontrol,ortypeBslidingbarrierdeviceasthepointofoperationsafeguard.Twotypesofbrakemonitorsarecommon–topstopoverrunandtimebasedsystems.Thefirstischeapandhardtoadjust.Furtherit’sapassivedevicewhichisnevercheckeduntilthebreakwearstothepointthepressblowsthroughtopdeadcenter.Finally,itfailstomeasuredownstrokestoppingperformancerequiredtoestablishsafetydistance.Anelectronictimebasedmonitorresolvesalltheseshortcomingsandishighlypreferred.Upcomingarticlewilltreatsectionc“safeguardingthepointofoperation”IfyouhavequestionsaboutOSHAcompliancecallusat(800)863-3164.WeofferinplantOSHA/ANSIcompliancesurveys!
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