Life factor for contact stress

Symbol ZNT10
Unit -
Attribute-ID stress_cycle_factor_pitting_resistance_z_nt10_agma_2003
Numeric ID 9887
Value Type PMDouble

The life factor ZNT10 determines the slope of the bending fatigue life curve, and thus the decrease to the allowable contact stress number between the load cycle numbers NL = 109 and NL = 1010. It can be specified for the calculation of the life factor ZNT according to AGMA 2003.

For NL = 109, ZNT = 1.0 applies.

If the allowable contact stress number should not decrease in this range, ZNT10 = 1.0 must be entered.

If ZNT10 is not specified, ZNT is calculated according to AGMA 2003 with decreasing allowable contact stress number.

The life factor ZNT10 is only used for the S-N curve calculation. If a component S-N curve is specified in the material of the respective wheel, it is used for the load capacity and load spectrum calculation.