Dear Forums member,

Could someone explain how to input allowable stress for ERW pipe follow ASME B31.1 App.A without created new material libraly, If I use Eff 0.85 Caesar will multiplied of allowable stress for seamless pipe.

Best regards,

Siampol.

You can manually override the listed values in the input.

Regards,

Thx Dan.

I wonder if there are some B31.1 experts that can explain how the Eff factor is realy used in Caesar. My opinion is that it is a misunderstanding.

Regards,

The usage of this field varies by Piping Code. Check the "help" for this field, all the details are there.

"Eff
The longitudinal weld joint efficiency. The use of this parameter by CAESAR II varies with the piping code. Depending upon code requirements, the allowable stress may be either divided by Eff for use in the flexibility calculations or multiplied by Eff for use in the minimum wall calculations. The following describes the effect of the longitudinal joint efficiency for each of the piping codes.
B31.1, B31.1-1967, B31.5. Allowable stress tables include Longitudinal Weld Joint Efficiencies where applicable. If Eff is entered, values for SC and SH will be divided by Eff before being used in the flexibility calculations. Eff will be ignored in the minimum wall calculation."

My question is only for B31.1.



I still have some dificulties in understanding this in relationship with the materials listed in Caesar.

So to summarize, for B31.1, this field is to be used only when for ERW pipes we create new material or manually modify the allowables and not with Caesar listed materials as they are only for eff = 1. Wright or wrong?

Assume that I have a 16" ERW pipe A312 TP316, how can we input this in Caesar?


The danger as I see is that someone that is familiar with B31.3 will take the material listed in caesar and will apply the eff = 0.85. This will result in a increased allowable.


Regards,

You're right, that would be an incorrect use of the field.

Thank you Richard.

Siampol, we have now the answer.

Best regards,