Hi stress community

I would like your opinion of the following:

1) Case: modular work-Do you usually consider imposed deflections on pipe, due to structural movements during lifting procedures of modules?
My opinion is as follow: a few rest supports of the system may not be working during lifting, due to platform deflection, especially at the middle span of the platform. If deflections are significant, it should be checked as a SUS case WNC case & OCC deleting rests supports not used. However, pipe has no temperature, pressure and it may not be connected to equipment therefore it might not be that relevant this checking.
On the Displacement case, no stress should be checked, since the pipe has no temperature and really the EXP case due to D1 only, where D1are the platform moments, makes no logic since the pipe is not fully anchored on every single support and therefore no deflections on the pipe will be imposed. On the other hand, “sea fastenings” may be considered as anchors …..
2) Do you usually recommend flange disconnecting of equipments due to the above? An idea, on this case, is to introduce a dummy spool to be bolted at site when modules arrive…..


Thanks for comments.

Hi OG,

I have worked on a project similar to yours. The module was transported on its horiz axis due to its vertical height so we had a number of restraints specifically included to support the pipework during transportation. I checked the the SUS case as you did, WNC but I also did a HYD case with Water Filled Weight as some of the pipework was tested on the module. Connections to equipment were done at site with tie-in spools to remove any unwanted movement at the nozzles. On the jobs I have seen this seems to be standard practice.

Hope this helps.