Define menu>Components>Expansion joints. CSiPlant expansion joint component offers integrated options to model tie rods with or without gaps, effective inside diameter area for consideration of pressure thrust, and options to apply linear or multi-linear breakaway stiffness values in each direction. Quick-model options for hinge and gimbal joints.
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Expansion joint local axes are the same as piping local axes, displayed below in line view with colored arrows. Red arrow points to local +1 (U1) longitudinal direction, green arrow points to local +2 (U2) which is vertical with horizontal piping, and blue arrow points to local +3 (U3), so R1, for example, would be torsional stiffness. The same colored arrow convention with red local 1, green local 2, and blue local 3 can be displayed for local axes of supports, joints, frames, and local axes of links.
Convoluted modeling approach required by other pipe stress software:
