Life is typically rated at 90% confidence (L10 standard), which represents time at which 90% of assemblies still perform. The dynamic load rating can be used to calculate the L10 life of the screw system. For inch series screws L10 life is calculated in inches of travel by the equation
Where 𝐶𝑎𝑚 is the dynamic load rating and F is the operating load. Metric series L10 life is calculated in total revolutions by equation below.
Factors that reduce life are shock loading, vibrations, temperature, lubrication, misalignment, etc.