Aluminum Extrusion Troubleshooting

Waving

Problem Description

The profile displays periodic wave-like distortion along its length, often worsening toward the billet back end.

Cause–Correction Mapping
  • Excessive back end billet temperature
    Cause in: Equipment

      Corrections

    • Taper billet temperature.

    • Reduce speed towards back of billet.

    • Reduce billet length.

    • Decrease billet temperature.

  • Excessive pressure in die
    Cause in: Equipment

      Corrections

    • Raise billet temperature.

  • Improper bearing length
    Cause in: Die

      Corrections

    • Cut bearings shorter in area hold back.

  • Insufficient bolster support
    Cause in: Die

      Corrections

    • Provide better bolster support and check pressure ring.

  • Uneven flow
    Cause in: Die, Profile

      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 Waving 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.