There is some question as to what effect pressure has on the stiffing of straight pipe. This would be a consideration on riser piping where you have high pressure and long straight runs.

The "pressure stiffening of straight pipes" was an attempt to incorporate stress stiffening into the analysis. We found no outside corraboration of this methodology for piping, so in Version 5.00 it has been removed.

I highly suggest you don't use this option.

Dear Richard Ay,

As you have said you don't suggest to use this option. I get different result if i use this option, I know little about pressure stiffning, can you throw more light on it ,or is there any paper/comments or something discuss "pressure stiffning of straight pipe", so that i can learn some knowledge about it especially to power piping(such as 10Mpa or higher)

Comments from anyone else are also welcome!!

Thank you!

There is no paper, this was all unpublished and internal work. Yes you will get different answers, but after several years of research, we can't coraborate the results. Don't use this option.

OK,
Since the software supplied this option ,I guess there must be some pipings have used this opiton in some area in this world. Will those
analysis which have used this option cause un-conservative results or any other problems?

Thank you!

Best Regards,

I can't answer that question with an certainty. If you're concerned about a particular job, then rerun it.