We wish to report a major error in ASME B31.3 2014 edition, in which supports that are not lifting off are incorrectly marked as lifting off under operating condition. Such supports are removed in the subsequent analysis performed on the same analysis set. The results obtained for such an analysis set will be incorrect and overly conservative. When will this defect impact your current B31.3 2014 edition results? Some Comments below:
1. This defect will only impact the results for the analysis set with the “Remove Lift-off Support” option enabled. Note that the sustained stress value calculated for the impacted analysis set may also be used in calculation of occasional stress for other combinations.
2. Using the option “Multiple analysis sets (B31.3)” under the “Create Default Sets” drop down on the Analysis Sets dialog generates analysis sets with the option “Remove Lift-off Support” enabled by default. Such analysis sets may also be impacted by this defect.
In general, this defect will incorrectly result in an overly conservative sustained stress value calculation as a support which was not supposed to lift-off is removed for generating the results. As the occasional stress uses the maximum sustained stress value from across all analysis sets, the occasional stress may also be incorrect and overly conservative.
For all other piping codes and B31.3 2012 and earlier editions: When a non-linear analysis is performed for a model with v-stop or guide supports with a gap in the upward direction, AutoPIPE may incorrectly display a warning message for v-stop or guide support lifting off under operating conditions. The warning message serves as an alert to the user that at least one support has lifted off in the model for an analysis set. The Support Forces and Code Compliance report will display correct results regardless of the warning message.
This defect will be corrected in AutoPIPE CONNECT Update 1 to be issued in mid December.
Any questions please contact Technical Support Group (TSG) - support@bentley.com
The software release that fixes this error is now available for download.