A TTE SOLUTION:

The Difficult Die - A rectangular hollow is running convex. Brainstorming - Looked for the following:

1. Square bearing surfaces

2. Bearing lengths and transitions

3. Blanched porting

4. Excessive post bearing due to deflection

5. Review samples for consistency from front to back, etc.

Findings

1. The mandrel has short travel or "beam" which was compromised for the speed of the extrusion. This caused the housing to deflect or "cave" and the mandrel bearing shifts beyond the die plate bearing.

2. The shallow weld chamber resulted in the corners starving for metal.

Solution

We redesigned the die with more travel/beam on the housing and a deeper weld chamber to allow for appropriate strength and flow. The aluminum is allowed to mix and weld properly together at the die face.

Outcome

The corrections to this die had a positive effect! The deflection was reduced. The concave situation was eliminated, and the front to back variation in the extrusion was minimized.