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The Advanced option enables users to define multilinear force/displacement and moment/rotation relationships to specify allowable movements in each selected degree of freedom, making it also suitable for modeling ball joints and , couplings, telescoping slip joints, and flexible hoses among other applications. Please note that rotational stiffness is entered using radians, with no current option to enter in degrees.
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Directional stiffness properties are applied in local axes. Expansion joint local axes are the same as the connected piping and can be displayed using the 'Set display options' 
. Pipe and expansion joint local axes shown below.
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.
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