Hydro Bend test via ASME VIII Div2

[MG83]

Hi,
According to B31.8 para 833 we have to consider bending moment on pipeline equipment such as Insulating Joints. So we perform hydrostatic pressure + Bending test on a prototype equipment.
The question is "how to use div2 part5 criteria in such test?" and "how to interpret the stresses derived from hydro bend analysis?"
What i did is:
1- Elastic analysis with design pressure 2000psi.
2- Elastic-Plastic analysis with 2.4xDp
3- Ratcheting analysis with 1.7xDp
4- Elastic analysis with test pressure 4000psi+ bending force 270klb-f.
Regards.

 

[TGS4]

Are you expecting (pseudo-elastic) stresses beyond yield? If so, then I would not use an elastic analysis. It will not provide any information.

What, exactly, are you trying to obtain from the prototype and the subsequent FEA?

 

[MG83]

I just want to design an equipment via FEA according to viii div2 part5.
As you know there is no exact rule for hydrostatic test in part5. How we can use B31.8 rule for protottpe test in fea?

 

[TGS4]

As you know there is no exact rule for hydrostatic test in part5.

That is incorrect. I can say that very authoritatively (because I wrote the pressure test rules in Part 5).

If you want to design equipment using VIII-2, I recommend by starting with a training course.

 

[MG83]

Thanks but Please adress the pressure test rule in part5. Is it in 2019 edition of asme? I remember that I have read a thread which you(tgs4) told that '' we are working hard to add pressure test rule in 2019 edition''. Please inform me because i don't have an access to training courses in US.
I am familiar with protection againt plastic colapse. Just tell me how to consider asme rule for bending test load in fea.

 

[TGS4]

The pressure test rules actually were incorporated in the 2017 Edition.

Where are you located? There are courses outside of the US (Canada, for example...). I'm not aware of any quality public courses offered outside of North America. However, some training providers offer Virtual Attendance, which allows you to attend the course without physically attending the course location. You might just have to deal with a large time difference...

Just tell me how to consider asme rule for bending test load in fea.

Unfortunately, you are requesting something that cannot be provided, for free, over the anonymous internet.

 

[MG83]

Dear TGS4,
Thanks a lot for your advises but we can not attend in such courses because of US unjust sanctions!
leave it over.

As you told, I found new rule for testing in 2017' edition which in my case it is equal to 1.69Pt + Wpt for global criteria.
But a question still exists:
I have a bending load which acts with hydrotest simultaneously that you can see in attached image.
shall i add factored load 1.69 to {hydrostatic test pressure + bending load} together. In such situation the solution will not converge at all because of local stresses.

Regards

 

[TGS4]

There are courses outside of the US (for example, in Canada).

I do not understand what you mean by local stresses.

 

[MG83]

I mean stress concentrations in discontinuities for example where the hub rings attached to the pipeline.
In elastic analysis for hydrotest, code told that we have not to consider local and secondary stresses but what about E-P analysis ?

Let me review:
A-The design pressure is 2000 psi. For E-P analysis the factored load is 2.4x2000=4800 and the solution will converge.
B- hydrotest pressure is 1.8xdesign pressure + bending load 270klb-f. So for E-P analysis the factored load is 1.69Pt= 6000 psi + 450 klb-f. And in such pressure the solution will not converge at all.
What is my mistake?