Hydrotest Pressure Extension

Users can decide whether pressure extension should be considered in static analysis sets, but this is not an option for hydrotest cases. The user is required to consider it with no option to unselect "Pressure Extension" in the "Analysis Sets" interface. While pressure extension is a real effect, it can generally be regarded as negligible for most metallic piping systems with smaller D/t ratios. The magnitude of displacements associated with pressure extension on such systems tends to fall within the margin of error of simplified fully elastic stress analysis models, like those handled in AutoPIPE. When considering the default stiffness associated with pinned supports in the hydrotest case, loads due to pressure extension are greatly exaggerated in certain areas and are unable to be handled in the support design. AutoPIPE should allow the user to toggle pressure extension on or off, as needed, as with any other static analysis set.