| Applies To | |
| Product(s): | AutoPIPE |
| Version(s): | ALL; |
| Area: | Calculations |
| Date Logged & Current Version | May 2023 23.00.00.230 |
Problem:
Questions and answers related to effective axial force calculations / results provided in the program
Solution:
Question: Kindly advise whether this version of AUTOPIPE is capable to calculate effective axial force directly. If yes, kindly advice how to get it in autopipe result.
Answer:
Yes, under restrained conditions, the axial force is he same as the true wall force. However for unrestrained pipe there may be some deviation.
Question: Based on the FAQ#36 found in online help shall be used ?.
In this case S = N + PeAe - PiAi understand that, S - effective axial N - Force extracted from autopipe results, Pe - External pressure due to water column, Ae - Overall area of pipe, Pi - Internal pressure, Ai - Internal area of pipe. Further, please clarify on my understanding. Incase autopipe result axial forces are in POSITIVE, that means axial forces are in compression. So that we have include negative sign while calculating effective axial force in above effective axial force.
Answer:
Yes, AutoPIPE will output a compressive force positive value.
Question: Post query: When we do some sensitivity. we have noted that, when the pipeline is modelled with both side rigid anchors then the autopipe axial force is approximately matching with the Seff force provided by DNV for fully restrained pipe. Whether we can conclude that for fully restrained autopipe model directly we can use the autopipe axial force as the Seff force. In that case how to find out the Seff force for unrestrained section of pipeline. Request your confirmation on restrained sections and for unrestrained section of pipeline FAQ#36 shall be considered for calculating effective axial force.
Answer:
Again, for a fully restrained model AutoPIPE will report the same effective axial force
Note, see here for similar concepts.