	Applies To
	Product:	AutoPIPE
	First Affected Version:	9.1.0
	Found in Version:	11.00.00.22
	Fixed and Released in Version:	11.01
	Area:	All
	Severity:	Critical
	Backlog Issue Number:	702082

Problem Description

ASME NC and ND, Level C/D reversing dynamic stress summaries use branch pressure and geometric properties for pressure term calculations of "P + WGT + Rev. Dyn" stresses at a tee point. Program should use header pressure and geometric properties for these calculations as the moment term for these stresses use tee moment summation.

Steps to Repeat

1. Open Walkthru model and change piping code to ASME NC 2001 edition

2. Apply an impost support displacement on load case S1 of 1" in global X direction at node B04

3. Navigate to Design Pres/Temp grid, and change the Design Pressure value for the tee branch from A05 up to B04 to 500

4. Launch the SAM Analysis dialog (Analysis > Analyze > Seismic Anchor Movement) and enable "SAM case 1" and press OK

5. Analyze the model for Modal, static and SAM analysis

6. Launch the Code Comb. tab of Load Combinations dialog, uncheck the Auto Update checkbox and then check the Reversing Dynamic check for Static Seismic 1{1} combination

7. Launch the stress summary dialog, create a new Level D Reversing Dynamic stress summary by selecting the following:

Sustained Load = Gravity{1}

Reverse Dynamic Load = Static Seismic 1{1}

Anchor Motion due to Rev. Dy. = S.A.M. 1

8. Take out the stress summary output report

Notice that the stress value for P+WGT+Rev. Dyn stress is different for between header nodes (A05 -, A05 +) and Branch A05, whereas they should be the same as the program is using tee moment summation.

Evaluation Criteria

Workaround

Solution

The fix for this defect shall be two fold. First, AutoPIPE shall use the tee summation definitions as required by NB-3683.1(d) for both NC and ND Reversing Dynamic, all editions. Second, AutoPIPE shall perform tee summation definitions as required by NB-3683.1(d) for both NC and ND non-reversing dynamic (all levels), editions 1983-2001. This was not a requirement of CTC, but determined by the development team as a needed update. For editions earlier than 1983 or later than 2001, NC/ND stress calculations shall be performed for each tee leg independently, as required by NC/ND-3653.3.

Also See:

Critical and High issues released in v.11.01.00

Known Issues in AutoPIPE (Enhancements, defects, etc..)