Hi.
according to ASME Viii Div2 Figure 5-1
the criteria for Sum of PL+PB+Q+F is 2x Sa.
I always consider my maximum stress to be less than it.
But in 2017 version, this criteria was just Sa.
The range of P+Q+F is always divided by 2 to calculate the stress amplitude. The calculated stress amplitude is compared to the allowable value. The correction made in the 2019 Edition to correct this (potential) misunderstanding.