Aluminum Extrusion Troubleshooting

Twist

Problem Description

The profile rotates along its longitudinal axis during extrusion or cooling, increasing with length.

Cause–Correction Mapping
  • Bearing squareness
    Cause in: Die

      Corrections

    • Square the bearings perpendicular to the face; flatten bearings perpendicular to metal flow.

  • Improper support while metal is hot and soft
    Cause in: Equipment

      Corrections

    • Correct bridging/blocking of run-out table.

  • Press alignment
    Cause in: Equipment

      Corrections

    • Adjust lead-out table to proper height.

  • Uneven billet temperature
    Cause in: Equipment

      Corrections

    • Adjust temperatures as required.

  • Uneven metal flow
    Cause in: Die

      Corrections

    • Adjust ports to control metal flow.

      Advantage: Easier to control flow by port adjustment.

    • Adjust bearing length to control metal flow.

Please note that the information provided in this article is intended to be a general guide to the causes and corrections of Twist in aluminum extrusion. However, it is important to note that the specific cause and correction of any particular defect will vary depending on the specific extrusion process, alloy, and other factors. Therefore, it is important to consult with an experienced and professional engineer to ensure that the correct diagnosis is made and the most suitable correction is chosen.