Extrudate shrinkage control and reduction
US6695606B1 · kind B1 · utility
8Cited by
14References
8Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jul 25, 2000 |
| Grant date | Feb 24, 2004 |
| Priority date | — |
| Expiry date | Jul 25, 2020 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29L2030/002
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
An extrusion apparatus for extruding visco-elastic materials includes an extruder head for preliminary shaping of a visco-elastic melt and a splice bar die assembly for final shaping of the visco-elastic melt. Both the extruder head and the die assembly have flow channels that include low elongational flow zones where elongational flow is reduced and controlled, thereby reducing and controlling the resulting shrinkage of the extrudate. Extrudate shrinkage can also be reduced and controlled by controlling the die swell of the visco-elastic melt by rotating the roller at a selected roller speed less than the melt speed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.