The Non-linear method is a sequence of applied load cases as defined on the initial states dialog. For example, a guide support with 0.2" gap left / right, non-code combination GT1E1, is analyzed by:
When connecting supports to beams or anchors, any movement allowed in these components will directly influence the connected piping movement.
Example, vertical pipe pipe with guide support that has 3" gaps in all directions connected to a horizontal beam that is anchored on the other end. The support can move more than 3" in any direction under operating conditions IF
a. The Beam's characteristics are not rigid.
b. The anchor's characteristics are not rigid.
Additional movement might be applied to any anchor by defining Thermal Anchor Movement. in addition, both anchors and supports could have Imposed Support Displacement defined. Both of these conditions would directly affect a support to have movement more than defining gap distances.
Make sure you check the Stiffness setting on a support. If set to anything other than Rigid, a support's gaps may close, and applying enough force may overcome this setting. Consequently, more pipe displacement is possible.
When reviewing the different sub-reports of the output report, be sure to confirm which axis is being used for the printed results: Global or Local. See the following example for a common mistake
Example: In the image below, the guide support at node F04 was set to 20.98mm left / right.
When reviewing the Displacement sub section of the output report, Gravity load case movement was measured = 27.354 mm.
This clearly exceeds the gap setting above, clearly AutoPIPE must be wrong, correct? NO not correct, AutoPIPE is functioning correctly !!!
Recall from your official AutoPIPE training that a guide bearing springs are always perpendicular to the pipe orientation (both horizontally and vertically), and note in the image above that the pipe is not oriented on a global axis. Also recall from the training that the Displacement sub-report and Displacement tab of the Results Grids has values that are based on Global axis movement, and NOT Local axis movement.
Therefore what is the local movement at this support perpendicular to the pipe?, Which AutoPIPE sub-report has the Global and Local moments results printed automatically?
That is correct, the Support sub-report. Therefore, create and review the Support sub-report, (see image below):
Note that the Local movement is exactly the same as the support gap setting (ex. 20.98 mm), meaning that the Load cases has caused the support gap to close completely and that the pipe is now exerting a force on the support.
Again do not be fooled by the movement exceeding the gap setting; the Global displacement results = 27.354mm, but the true local distance movement was 20.980 mm.
Bentley AutoPIPE