1. Principle of the process Design For Manufacturing (DFM)
Structure
Process modeling
Defects / control
Design For Manufacturing (DFM)
Process variation
Module 5c

2. Shaping Processes For Plastics - Extrusion
Die configurations and extruded products
Extruded product depends on the shape of die
Solid profiles
Module 5c

3. Die configurations and extruded products
The main quality problem is related to
There are several methods to overcome the die swell
a. Increase die opening length
b. A operation follows the extrusion
c. For non-round shape, a correction is needed.
Correction
Desired shape
Module 5c

4. Die configurations and extruded products
Defects in Extrusion – melt fracture
Turbulence flow at the entrance of the die
Module 5c

5. Die configurations and extruded products
Defects in Extrusion – sharkskin or bambooing
Friction between die and extrudate
Module 5c

6. Principle of the process Design For Manufacturing (DFM)
Structure
Process modeling
Defects / control
Design For Manufacturing (DFM)
Process variation
Module 5c

7. Design For Manufacturing – Plastics Extrusion
is a root cause. In the figure below, there are three common types of problems
Module 5c

8. Design For Manufacturing – Plastics Extrusion
Module 5c

9. Design For Manufacturing – Plastics Extrusion
Module 5c

10. Design For Manufacturing – Plastics Extrusion
DFM guideline – wall thickness:
Module 5c

11. Design For Manufacturing – Plastics Extrusion
DFM guideline – wall thickness:
Module 5c

12. Design For Manufacturing – Plastics Extrusion
DFM guideline – wall thickness:
Module 5c

13. Design For Manufacturing – Plastics Extrusion
DFM guideline – sink marks:
Module 5c

14. Design For Manufacturing – Plastics Extrusion
DFM guideline – hole location:
Module 5c

15. Design For Manufacturing – Plastics Extrusion
DFM guideline – hole location:
Module 5c