In my opinion, it is important to borrow a concept from the nuclear power industry on reasonable seismic allowable nozzle loads.
They define a loading case where there is damage, after a seismic event, but the equipment does not have to be able to operate. ( Safe Shutown case)
In this case, the calculated stresses in piping systems, (and presumably equipment nozzles) are allowed to go to 0.9 Fy. Unless it is safety related, the equipment does not have to again function.
If you can get such a loading condition from a vendor, it would answer your questions.
-MJC