CentreholegrindingmachineZSMCentreholegrindingmachineZSMseriesWithmorethantwothousandcentreholegrindingmachinesbeingoperatedbycustomers,theZSMisoneofthemostsuccessfulmachinesystemsbuiltbySWISSMANandamongthebest-sellingcentreholegrindingmachinesintheworld.AreasofapplicationZSMCuttingtools,grindingmandrels,toolholders,tempereddriveshaftsandgearshaftsarejustsomeexamplesofworkpiecesonwhichcylindricalgrindingmustbecarriedoutwiththegreatestprecision.Thequalityofthecylindricalgrindingisstronglyinfluencedbytheset-upoftheworkpieceandthereforebytheexactgeometryofthecentrehole.Withitsuniquesimultaneous3DgrindingwheelmotionsthecentreholegrindingmachineZSMfabricatesageometricallyhighlyprecisecentre.Theworkpieceismountedinastationaryandself-centeringposition:1.Rotarymotionofthegrindingwheel2.Planetarymotionofthegrindingspindle3.OscillatingmotionofthegrindingwheelalongtheconicalsurfacetobegroundComponentpartfabricationDuetoitsmodulardesign,theSWISSMANZSMissuitablebothforcomponentpartandhigh-volumefabrication.TheZSM810modelhasamanualgrindingheadinfeedandasemi-automaticdressingdeviceandispreferablyusedforcomponentpartandsmallscalefabrication.High-volumefabricationTheSWISSMANZSM815isequippedwithanautomaticprogramflowforhigh-volumefabrication.Allgrindingparameterscanbeprogrammedasdesired.Thedressingprocessisintegratedintothemachiningprocess.Forrepetitiveworkpiecestheoperatorcanenterthecorrespondingpart-specificgrindingdata.Thegrindingresultsarethereforepreciselyreproducible.Grindingisalwaysperformedunderthesameconditions,regardlessofwhoisoperatingthemachine.2123.3345612.1.TheSWISSMANgrindingprincipleCentreholegrindingmachineZSMPrecisecentreholesThegreaterthedemandsonprecisionofcylindricalgrinding,themoreimportantistheset-upoftheworkpieceandthustheexactgeometryofthecentreholeinwhichtheworkpieceismountedtodeadcentresforcylindricalgrinding.ThefollowingfeaturescharacterizegeometricallyprecisecentreholesfabricatedonaTechnicacentreholegrindingmachineZSM.RoundnessdeviationInconventionalgrindingprocesses,ovalcentreholesareoftenproducedthatcanleadtoundefinedworkpieceset-ups.TheSWISSMANZSM,however,grindsgeometricallyroundcentreholesandpermitsadefinedworkpieceset-up.•Achievableroundnessdeviationofcentrehole<1µmAxialalignmentAsshownintheadjacentfigure,non-alignedcentreholesrepresentanadditionalsourceoferrorincylindricalgrindingoperations.TheSWISSMANcentreholegrindingmachine,however,grindsgeometricallyalignedcentreholeaxes.•Axialalignmentofcentrehole<10µmAngleAnglesincentreholesthataretoolargeortoosmallalsoleadtoundefinedset-upsoftheworkpiece.TheSWISSMANZSMgrindsaprecisetaperangleof60°.•Angletoleranceoftheangle<1’anglesec.GrindingpatternDuetothethreesimultaneousgrindingmotions,theZSMfabricatesahomogeneouscross-grindingpatternwithmicroscopicoilpocketsthatformaconstantoilfilmbetweentheworkpieceanddeadcentreofthecylindricalgrindingmachine.Thispreventsdryrunningandseizingofthedeadcentreandeliminatesanadditionalsourceoferrorforhighqualitycylindricalgrinding.•SurfaceroughnessofthecentreholeN4-N6=0.2-0.8µm456CentreholegrindingmachineZSMSWISSMANAGSportstrasse332540GrenchenSwitzerlandDressingdeviceThesemi-automaticdressingdeviceismountedtothesideofthegrindingheadandisswiveledintothedressingpositionmanually.Whendressing,thegrindingwheelturnsonlyarounditsownaxis.Duringthedressingoperation,inadditiontothelongitudinalmotion,thediamondsimultaneouslyperformsasidewaysoscillatingmotionalongthegrindingwheelcone.Regardlessofthepositionandthewearofthedressingdiamond,thisensuresaconstant,geometricallypreciseconicalshapeofthegrindingwheel.IntheZSM815model,thereisalsothepossibilityofdimensionalcompensationofthedressingvalueviaCNCcontrol.WorkpiececlampingdevicesTheself-centeringclampingdevicessimplifyworkpieceset-upinthecentreholegrindingmachine.Dependingoncustomerapplication,variousworkpiececlampingdevicesareavailable.AdditionalaccessoriesWiththeworkpiecedrive,mountedworkpiecescanberotatedadditionallyat48¹/min.,whichpermitsahigherdegreeofconcentricitybetweencentreholeandoutsidediameter.Forfrequentlychangingcentrediameters,usingthecontinuouslyadjustablespeedregulationofthespindleisrecommended.CentreholediameterWorkpiececlampingrangeWorkpiecelengthandweightCentreholeangleGrindingspindlerpmø1-60mmø4-220mm50-1100mm(specialversion50-2800mm),max.120kg60°upto45’000revolutionsperminuteE-1500-07/067788KeyfiguresofthecentreholegrindingmachineSWISSMANZSMseriesCentreholegrindingmachineZSM