Why are AutoPIPE's code stresses results so different in a model analyzed per ASME B31.3 - 2010 compared to ASME B31.3 - 2012?
In AutoPIPE, create a model called 2010.dat with the piping code set to ASME B31.3 - 2010 edition and save the file. Save the same file again as 2012.DAT, again changing the piping code to ASME B31.3 - 2012. At this point there are 2 models: 2010.DAT and 2012.DAT both are identical except for the pipe code is 2010 in one model and 2012 in the other model.
Open each model in a different instance of AutoPIPE, analyze both models, create a complete model listing (Tools> model Input Listing> check all sub reports ON), then create a complete Output Report (Results> output report> check all sub reports on except "Sorted Stresses", and then press OK button. In a few moments both reports should be generated and displayed in AutoPIPE View.
Navigate to the folder where the model is stored, locate both OUT files (2010.OUT and 2012.OUT). Using an application (i.e. Ultra Compare, Beyond Compare, WinMerge), compare these files to highlight all the differences between both files. A few node points are shown below:
As can be clearly seen there are major differences in some of the results, why?
Please see the following AutoPIPE help section:
Help > Contents> Contents Tab> Reference Information> Code Compliance Calculations> ASME B31.3 2010 and 2012, see the section for "Thermal Expansion Stress Range"
Notice the difference between the code calculations.
One should expect the results to be different from one code year to the next. It is not for Bentley TSG to provide a code interpretation, but for you to investigate the issue. Star your investigation by reviewing AutoPIPE's help Code Calculations section mentioned above for the respective codes / years. Then continue your investigation with the actual code documentation Next, suggest to generate a complete model output report for each code / model and compare them using an application like (Beyond compare, Ultra Edit, etc..) to uncover more settings that may have changed besides calculations alone.
ASME B31.3 Piping Code Calculation Issues