Anchor loads near expansion joints

Posted by: Piper

Anchor loads near expansion joints - 04/07/11 12:08 AM

Hi everybody

I have to check loads of an anchor just between two expansion joints near flare nozzles and a 270° c. 8 in. line . I mean the arrangement is flare stack + expansion joint + anchor point+8 in pipe respectively. Loads are to be checked to make sure that steel structure can tolerate them.Please also see attached file.
As I know the loads are the sum of friction loads, pressure thrust loads and expansion joint’s spring force. How precise could the loads be if I just modeled the piping system till the anchor point? Are there any important points that I should consider analyzing the job?

Thanks in davance
Posted by: danb

Re: Anchor loads near expansion joints - 04/07/11 01:30 AM

If you stop your calculation as you intend, you will miss the "pressure thrust loads and expansion joint’s spring force". So you can extend your calculation up to the next anchor, or you will manually calculate and add these forces.

But expansion joints on flare line? Not such a good idea.


Regards,
Posted by: Piper

Re: Anchor loads near expansion joints - 04/08/11 11:36 PM


Using expansion joint is the vendor's idea and also in its scope of design.
Regarding the loads other than friction, thrust and spring force what could happen to loads like sustained and seismic loads?

Thanks
Posted by: danb

Re: Anchor loads near expansion joints - 04/09/11 12:13 AM

Yes, you should combine the mentioned loads from vendor side with the loads from your side.

Regards,
Posted by: Piper

Re: Anchor loads near expansion joints - 04/11/11 01:12 AM


Which forces / moments could be large in size if you had to judge?Note that a vertical run exists after expansion joints to top of the flare stack.

Thanks
Posted by: danb

Re: Anchor loads near expansion joints - 04/19/11 02:22 AM

Ask vendor to give you the loads from his side and combine them with yours.
Let him to take responsibility for his part.
Regards