How to generate the load cases for Fatigue Analysis of FPSO topsides piping especially that due to wave induced loads & vibration of rotating machinery.

Regards

Ravi

Dave / Richard

Please let me know some example load cases for the same.

Regards

Ravi babu

This is a code consideration and not a software issue!


Did you try searching on FPSO????

Hi John

i tried searching in Google for FPSO . Search is not revealing me exactly the information what i want. I need to be more specific while searching. I am intrested at present only in the Load cases.

Regards

Ravi babu

In the December 1998 issue of COADE's Mechanical Engineering News, there is an article starting on page 18 that discusses Fatigue Analysis and how to set the load cases in CAESAR II. Pay particular attention to the "load state" diagram on page 20, and how you go from the diagram to the load cases used for analysis.

Richard

The one which you have shown the link , i have already gone through many times. The load cases mentioned there is due to pressure , temperature cycle induced fatigue.what iam intrested here is to generate the load case when the FPSO is subjected to Inertial acceleration & Sagging , Hogging Effect. Both these efects are cyclic and i need to generate the load cases for the above two effects.

Also let me know how to consider the load cycles for Sagging & Hogging of FPSO.For Inertial acceleration i know.

We need to consider the effect on Topsides Piping.


Regards

Ravi Babu

If you understand the above referenced article, then you understand the principle, which can be applied to any set of varying loading conditions. Your accelerations can be simulated as "uniform loads" (with the units of G's), and then you can take the difference between these cases applied a specified number of cycles.

Read through these threads ...


http://www.google.com/search?domains=www...0&SUBMIT=Submit

Thanks John

Could you please throw some light on Vibration Induced Fatigue as well.

regards

Ravi Babu