Support Type for offshore Riser flange (Hanger Flange)

Hi,

What type of support to be considered at hanger flange?
Will it be
1.Rest + 4 way guide (Flange is rested & allow to move up)
2.Anchor ((Flange is bolted or welded to structure platform:No movement)

1. What would cause the flange to move up ? Surely the entire riser weight is supported at this point. As you suggest will almost certainly be ok.

2. Would the attachment assembly actually prevent the tiny rotations that might otherwise exist, taking into account local flexibility of steelwork ? If not, model as translational restraint only.

MoverZ,thanks for the reply.

I just want to know what is the actual supporting arrangement at hanger flange.I have seen some of the platform photographs but it is not clear from those.

As per the process line list there is min design temp. which is less than Tamb. Because of this in Caesar II analysis it may cause to lift the support if I simply consider rest. (Also because of buoyancy...don't know in details)

The above two supporting arrangement would give different loading at hanger flange and the support before the hanger flange.

Please share your experience.

Full anchor modeled, what do you think from this drawing?

http://www.ephotobay.com/share/app-6-ref-info.html