Hi corne
Theoretically pressure force of pressure balance bellow should be absorbed by tie rod. But while modelling it in Caesar or in practical also very little effect will be there in support & nozzle .
One thing I miss in my previous post that I was told to make effect ID zero for In-line pressure balance bellow only.
For Tee type or elbow type pressure balance bellow, it act very fine in caesar with tie rod & effective ID of bellow.
But for in line pressure balance expansion bellow tie rod & effective Id of bellow do work properly in conventional simple modelling, that’s why when I work with in line pressure balance expansion bellow I put effective id of bellow as zero.