Calibration factor for safety assessment acc. to FVA 556/III

A safety against flank fracture can be determined based on the calibration factor c₂. For this purpose, the reciprocal value of the maximum material exposure is determined, taking the calibration factor into account.

$S_{FB}=\frac{1}{A_{FB,max}+c_2}+c_2$

Witzig suggests a value between 0 and 0.2 for the calibration value c₂. By default, the calibration factor c₂ = 0 is used, which thus corresponds to calculation of the safety against flank fracture according to FVA 556/I.

More detailed information on the calibration factors c₁ and c₂ can be found in Witzig and Boiadjiev:

1. Witzig, J.; Tobie, T.; Stahl, K.: Entwicklung eines erweiterten Berechnungsverfahrens zur Ermittlung optimaler Zahnflankentragfähigkeit bis in den Bereich großer Werkstofftiefen (Development of a calculation method to determine the optimal tooth flank load capacity up to the range of large material depths), FVA Research Paper 556/I, FVA Issue Nr. 1000, Forschungsvereinigung Antriebstechnik e.V., Frankfurt, 2011.
2. Witzig, J.: Flankenbruch – Eine Grenze der Zahnradtragfähigkeit in der Werkstofftiefe (Flank fracture - gear load capacity limits in material depth), Dissertation, 2011.
3. Bojadiev, I., Tobie, T.; Stahl, K.: Nachrechnung Flankenbruch Kegelräder (Recalculation of bevel gear flank fracture). FVA Research Project 556/III, FVA Issue 1100, Forschungsvereingigung Antriebstechnik e. V., Frankfurt, 2014.