Dear all,

Regarding above subject, I'm really wondering how we can get SIF when we meet D/t>100 discribed on ASME B 31.1 Appendix D note 1. As my experience, I have been used SIF by FEA but, it is limited only reinforced, unreinforced, or elbow. If we have to apply real SIF value for Tee and olet, please let me know how I can apply SIF for them.

Best regards,

Try to do this with Paulin software for SIF calculation and look in the Coade newsletter from December 1998 for modeling large D/d tee page 6.

Dear Friends,
Do you have any training material for FE Pipe developed by paulin?

Best

Dear Seok,

What is your FEA program to be used? Fe/Pipe?

I'm not sure, but I think Fe/Pipe has some limitations.

Why don't you use other FEA programs? Ansys, Nastran ...

Those programs could not give the SIF value automatically. But you can use the theory of Fe/Pipe.

The other way is you ask manufacturer to get SIF values. But I don't know how many manufacturers can give that value.

Good luck!

Thanks for reply.

However I'm still having questions as bellows;

1. Why ASME code is limitted by D/t>100?

2. Is there any problems if SIF produced by CAESAR II Program is applied even if D/t>100?

3. Why CAESAR II program allow that SIF is calculated even though not real SIF compared with ASME code is calculated automatically?

4. How about applying this method is that pipe thickness shall be increased to be correspond with code requirement if D/t>100?

I would be appreciated if antbody help me.

Thanks and Best Regards,

1) Because no one knows what happens if you exceed this. Therefore the Codes say the SIFs and flexibilities are limited to this ratio.

2) Maybe, hence the stated limit.

3) Because from a "computational" point of view there is nothing wrong. What would you prefer, an error that prevents you from running?

4) That would increase the weight and stiffness of the system.

... additional information ...

The highest ORNL test data point with strain gages is at D/T=100, and this may serve as a basis to limit the Code to that value.