Q.InDynamicBalancingdoweneedtosupportthecomponentonthe
machineinthesamelocationasinassembly ?
A.Yesitisnecessarytosupportthecomponentbeingbalancedatthe
sameornearaboutofthebearingsupportsforproperresults.
Dynamicbalancingisaforcebalancingandcouplebalancing
Operation.Thecoupleistheproductofforceandthedistanceto
thepointofsupport. Soitisessentialthatthereallifeconditionsare
replicatedonthebalancingmachines.
Q.InDynamicBalancingMachinedoweneedtorunthecomponent
beingbalancedtooperatingspeed/servicespeed ?
A.Usingadynamicbalancingmachinewemeasuretheunbalancein
theunitsofgrammillimeter. Thequalityandsensitivityofbalancing
Machinedecidesthespeedatwhichyoucanbalancea
Component.InmodernhardBearingdynamicbalancingMachines
Engineersareabletomeasuretheunbalanceatrelativelylower
Speeds.Theunbalancecorrectionseffectedarevalidformostof
Theservicespeedrequirementsofrigidrotors.RefertotheISO
1940standardstodeterminetheresidualunbalancepermittedin
rigidrotors.
Q. Whatarerigidrotors ?
A.Therotorswhichdonotchangeshapewhenspeedofrotation
Augmentations, ortheoneswhichdonotoperateatresonantfrequency,
areclassifiedasrigidrotors.
Q.Whatareflexiblerotors ?
A.Flexiblerotorsarerotorswhichoperateneartheirresonant
fréquence. Thisrunningofmotorgeneratesveryslightdeformation
oftherotor. Flexiblerotorsneedtobebalancedathigherspeeds
andalsoneartheirservicespeeds. Manytimes, insitubalancingis
requiredtoachievedesiredresults.
Q.Whataresoftbearingdynamicbalancingmachinesandhard
bearingdynamicbalancingmachines ?
A.Fewdecadesback, whenbalancingmachineswereintroduced, la
cradleonwhichtherollersweresupportedneededtobemovedto
measurethevibrationlevelsduetounbalance. Withtheadventof
technologyandintroductionofquartztransducerstomeasureforce,
itisnolongerrequiredforthecradlestooscillatetomeasure
vibration.
Themachineswhichcontinuedtohaveoscillatingcradlesand
electrodynamicpicupstomeasurevibrationwereclassifiedassoft
bearingmachines.
Themachineswhichhadrigidcradlesdevoidofanymovementand
measureforceusingpiezoorotherpicupsareclassifiedashard
bearingdynamicbalancingmachines.
Thebasicdesignphilosophyofhardbearingdynamicbalancing
machinesismeasuringforceandtheadvancementof
computationalmathematicsusingmicroprocessorshasenabled
introductionofbalancingmachineswhosecalibrationsarevalidfor
thecompleterangeofspeeds, weightsandqualityrequirements.
Thealgorithmusedfacilitatespermanentcalibrationandhostof
otherfeaturesfordaytodayuseandextremereliability.
