What are the most common load cases which to be considered for stress analysis of piping systems on a FPSO and how normally we define these loads for CII?

Is it possible to just go for Static analysis with some Dynamic load factors or Dynamic analysis is a “must to do” task.

Thanks

Hi Ali,
I assume you meant stress analysis of FPSO topsides piping, not subsea/marine piping. You should consider
1. Hull deflection and topside modules deflection due to hogging, sagging, rolling & pitching at all pipe & equipment support and enter it in diplacement field of CAESAR II
2. Induced acceleration on piping due to roll, pitch & heave are entered as uniform load, as U1, U2, U3
3. Fatigue life assessment, normally done based on DNV Note 30.2
4. Surge/hammer/load calculated, may be, using PIPENET transient & entered in force field of CAESAR II.
5. Booster compressors(reciprocating type) piping vibration analysis by vendor
6. Two phase lines natural frequency should be checked & kept above a min. value as agreed with structural dept. If there is slug flow, then it will be real difficult job.

Load cases are built to check code compliances as per B31.3 and for fatigue stress as per DNV Note30.2.
Hope this clarifies some of your doubts.
Regards,