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Deformations of a planet carrier aff ect the contact pattern between gears
INTEGRATING3D-FEA
In recent years, several programs for the design of machine elements in gear boxes like shafts, gears and bearings have seen the addition of 3D-FEA calculations. This article deals with 3D-FEA calculations, their usefulness and the features that should be supported
bearings. Shaft calculations often use nominal stresses and notch factors, and standards like DIN 743 or other analytical methods are used. For gear strength, analytical assessment methods like ISO 6336 or AGMA 2001 are used, while for bearings a life calculation according to
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oftware programmes for the design of machine elements focus mainly on analytical methods for assessing the strength of shafts, gears or
ISO 281 or ISO/TS 16281 is used. T ese methods are reliable for standard cases; they are fast and have been used for a long time.
WHAT IS 3D-FEA? Finite Element Analysis (FEA) is the use of calculations, models and simulations to predict and understand how an object might behave under various physical conditions. FEA calculations use the fi nite
element method (FEM), a numerical technique that cuts the structure of a 3D object into several pieces, or elements, and then reconnects the elements at points called nodes. T e FEM creates a set of algebraic equations which engineers, developers and other designers can use to perform FEA. Using FEA can reduce the number of physical prototypes created while also optimising all components during the design phase, providing the safe simulation of potentially dangerous or destructive load conditions and failure modes.
WHY THE NEED FOR 3D-FEA? T e fi rst point to mention is the improved consideration of stiff ness. T e housing stiff ness will aff ect the displacement of the shafts. T is will aff ect the contact pattern of gears and the tilting angle of bearings. For standard industrial gearboxes,
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