Can anyone please provide me standard load case for modular piping unit in FPSO with their definitions. I beleive that there are more considerations regarding FPSO. Thanks.

The Marine Technology Directorate (MTD) :

99/100 Guidelines for the Avoidance of Vibration Induced Fatigue in Process Pipework

http://www.mtd.org.uk/

http://www.mtd.org.uk/pubs.html

The CAESAR II template that builds the FPSO piping load cases should account for effects of (1) temperature, (2) internal pressure, (3) displacements due to hogging and sagging, (4) motion accelerations, including pitch-and-roll, and (5) wind. Suppose you apply B31.3 Piping Code, then you begin to combined listed load effects in terms of (a) Sustained, (b) Displacement and (c) Occasional. A distinct requisite for FPSO piping stress analysis belongs to (d) Fatigue. The latter, a cumulative exercise ranging from tens to 80 million cycles, defines a category by itself.

Since your firm specializes in skid design--i.e., not a general engineering company--your client or prime contractor should have provided you with some criteria here. Project documents, such as "Design Philosophy for Pipe Stress Analysis," would delineate which loads case be combined together.

Load cases compilation on FPSO piping, in my working, entails a humbling experience. Each numbers around 50 cases. Depending up variances, the project may need several templates, none STANDARD. Surely that of FRP piping differs from CS one.

Therefore, another FPSO stress challenge lies in the variety of piping materials used. CS, SS, FRP, Duplex, Super-Duplex, Titanium or Cu-Ni each possesses different properties that command unique attention. The thrust of FPSO piping stress analysis thus falls not only on the mechanics of CAESAR II programming, but also on finding all those properties and relating them to some justifiable stress equations and allowables.

None of what I have said suggests you should or shouldn't independently proceed with the task. But the FPSO piping stress analysis is kind of "esoteric," that is, perhaps only a handful of principal stress engineers or senior consultants have a firm grasp on it. Nor likely can this forum help you much beyond certain good intention suggestions. My advice to you is, asking first your client and prime engineering contractor for such assistance--they have more piping at stakes than those on your skids, presumably.