Restraints

Restraints are support elements or connection points for piping and equipment. PASS/START-PROF provides the following restraint types:

• Fixed Anchor (restrains rotation) - prevents all linear and rotational displacements. Transfers moments to the structure.

• Moment-Free Anchor - prevents linear displacement in all directions while allowing free rotation. Does not transfer moments.

• Guide Support (single-directional, double-acting) - prevents lateral displacement perpendicular to the pipe axis.

• Resting Support - prevents downward vertical displacement. Releases during upward movement.

• Variable Spring Support - restrains vertical displacement with variable spring rate.

• Variable Spring Hanger - restrains vertical displacement with variable spring rate.

• Rigid Rod Hanger - prevents downward vertical displacement. Releases during upward movement.

• Constant Spring Support/Hanger - maintains constant support force regardless of vertical displacement.

• Custom/Internal Restraint - user-defined restraints with non-standard properties.

• Equipment Connection  - models connection interfaces to equipment nozzles (pumps, vessels, heat exchangers, etc.)

• Marker - improves analysis accuracy by adding intermediate nodes. Does not function as a support.

Menu and Toolbar Access

To insert a restraint:

Select the target node, then use: Insert > Insert Restraint

or click the corresponding icon on the Insert Element toolbar.

To view or modify restraint properties:

• Double-click the restraint in the 3D View

• Select the restraint and click the Properties icon