doubts about static verification of a reducer subject to a load story

[alessi0_r]

Good morning to all, for a university project I am dimensionaling a reducer to 90°.
I have hypothesized a load story, from which to start for the sizing of the components, in which I have 3 blocks, each with a couple entering the different gearbox and relative numbers of cycles in which they act.
my doubt concerns static verification of the components, in particular what load to use, in relation to the 3 blocks.
With regard to fatigue testing, it is clear to me that I can define, through palmgren-miner, an equivalent load, which produces the same damage of the assigned load history, starting from the 3 initial blocks and using that for fatigue testing, calculating the average and alternate tensions, defined the fatigue admissible of the material etc.
regarding static verification, for example with von mises, which of the 3 blocks and therefore which of the 3 pairs should I use to make verification? I always use the equivalent load calculated before? or use the maximum torque of 3? or what acts for a greater number of cycles than others?

 

[pollo]

If it's static, what do you care about cycles?
It would be enough that one of them exceeds the admissible limit you imposed, and the verification would not be satisfied

 

[alessi0_r]

If it's static, what do you care about cycles?
It would be enough that one of them exceeds the admissible limit you imposed, and the verification would not be satisfied

perfect, thanks for clarification. I had come doubt thinking about the equivalent load calculated with palmgren-miner, where you actually get a "weighted" value compared to the starting ones, but in fact for static verification only counts the real load regardless of the number of cycles.

 

[meccanicamg]

for fatigue testing, calculations with miner the average value of the cycle and therefore the equivalent pair.
for static verification must be phosphated and verified the maximum load capacity of the most heavy cycle. static=no dynamic= no cycles.