Setting up Bearing Reference Surfaces

Use the BRS tool to select bearing reference surfaces.

The bearing is the last point of contact in the extrusion die where the workpiece takes the final desired shape. The bearing region is a critical part of the extrusion die, as it controls the metal flow through the die. The objective of the bearing is to have all parts of the profile emerge from the die at the uniform speed with minimal deflection at the exit.

To achieve the uniform exit speed with minimal deflection, the bearing region can be modeled as three segments called choke, straight bearing and relief as shown.

For complex models, meshing the bearing with choke and relief is a tedious process, and most of the time auto-mesh will fail to mesh it. As an alternative, HyperXtrude solver has an option to handle the choke and relief using the bearing reference surfaces on the die geometry.

The bearing reference surfaces are the surfaces on the tool geometry which represent the bearing region.

Solution methodology:

  • Extract the bearing reference surfaces from the die geometry.

  • Mesh the bearing solid using drag mesh with no choke/relief.

  • Use the 2D mesh of the reference surfaces to determine the choke angle and estimate the friction.

Creating Bearing Reference Surfaces

Use the BRS tool to select bearing reference surfaces.

  1. Click the Extrusion ribbon.
  2. Click the BRS tool.

  3. Inspire Extrude will automatically detect all of the bearing reference surfaces on the tool geometry.
    Automatically detected surfaces are shown in red.
  4. Press Ctrl and click surfaces on the model to add or remove surfaces by toggling between selected and unselected.
    Press Ctrl and drag to draw a box and unselect a group of surfaces even if they are hidden behind other layers.
    To unselect a single surface behind another surface, select that front surface and press H to hide it first.
    Note: Pressing H toggles the last selected surface between hidden and shown. Pressing S will show all of the hidden surfaces.
  5. Right-click and mouse through the check mark to exit, or double-right-click.