Hi Richard/ Dave,

Caesar II does not have an analysis option of pipelines as per Austrlian Standard AS 2885.1. May I request you incorporate this standard in your next version.

In the meantime do you suggest to use B31.4 as the closest code for the purpose of high pressure buried gas pipeline stress analysis?

There are a few problems I had faced trying to use B31.4 analysis.

1. The output is not doing any code stress check for second operating case below 21°C

2. The program is not accepting API 5L X42 for sub zero temperature

3. What formula (Tresca or Von Mises) is being used to calculate the combined equivalent stress (Hoop and total longitudinal stress) which B31.4 is comparing with 90% yield stress? It would be helpful if you can send a worked out example (may be for a couple of nodes) to show how the stresses are combined.

Thanks in advance for your help and time.

Regards
Soumen Guha

Not having seen AS-2885, I can't estimate what it would take to incorporate this into CAESAR II, however, I will add it to the Development List. We are getting close to finishing Version 5.30, so this Code will not be available in CAESAR II until Version 5.40 at the earliest.

1) B31.4 is setup to address "restrained pipe" in some load cases and "unrestrained pipe" in other load cases. So for a given load case, not all pipes meet the criteria.

2) Many of the pipeline codes have a lower temperature limit of ambient (21), or perhaps freezing (0). The data tables in these codes don't extend below these temperatures. Therefore this is the limit for the materials (in the CAESAR II Material Database). This is most likely the reason your having this problem.

3) The "code stress equations" are listed in the Quick Reference Guide.

See AS2885.1 appendix X7. It states that the stress criteria adopted in AS2885.1 are functionally identical with those of B31.4 and that B31.4 code calculations in standard software can be used without modification except that allowable stress limits may need to be ammended.