Cardan Shafts for Industrial Applications

Technical instructions for applicationBalancing of cardan shaftsThe balancing of cardan shaftsis performed to equalize eccentricallyrunning masses, thereforepreventing vibrations and reducingthe load on any connectedequipment.Balancing is carried out inaccordance with ISO Standard1940, “Balance quality of rotatingrigid bodies”. According to thisstandard, the permissible residualunbalance is dependent on theoperating speed and mass of thebalanced components.Dana’s experience has shownthat balancing is not normallyrequired for rotational speedsbelow 500 rpm. In individualcases, this range may be extendedor reduced, depending onthe overall drivetrain characteristics.Cardan shafts are balanced intwo planes, normally to a balancingaccuracy between G16and G40.• Balancing speedThe balancing speed is normallythe maximum speed ofthe system or vehicle.• Quality gradeIn defining a quality grade, itis necessary to consider thereproducibility levels achievablein the customer’s own testrig during verification testing.Quality grades are dependenton the following variables:• Type of balancing machine(hard, rigid or softsuspension)• Accuracy of the measuringsystem• Mounting tolerances• Joint bearing radial andaxial play• Angular backlash in longitudinaldisplacement directionField analyses have shown thatthe sum of these factors mayresult in inaccuracies of up to100%. This observation has givenrise to the definition of the followingbalancing quality grades:• Producer balancing: G16• Customer verification tests:G32G 40Car wheels, wheel rims, wheel sets, driveshaftsCrankshaft/drives of elastically mounted, fast four-cycleEngines (gasoline or diesel) with six or more cylindersCrankshaft/drives of engines of cars, trucks, and locomotivesG 16Driveshafts (propeller shafts, cardan shafts) with special requirementsParts of crushing machines and agricultural machineryIndividual components of engines (gasoline or diesel) for cars, trucks, and locomotivesCrankshaft/drives of engines with six or more cylinders under special requirementsG 6,3Parts of process plant machinesMarine main turbine gears (merchant service)Fans, flywheels, centrifuge drumsPaper machinery rolls, print rollsAssembled aircraft gas turbine rotorsPump impellersG 2,5Gas and steam turbines, including marine main turbines (merchant service)Rigid turbo-generator rotorsTurbo-compressors, turbine-driven pumpsMachine tool drivesComputer memory drums and discsExtract from DIN ISO 1940/Part 147