Polytetrafluoroethylene tubing and extruder for the production thereof
US6627277B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 18, 2000 |
| Grant date | Sep 30, 2003 |
| Priority date | — |
| Expiry date | Feb 18, 2020 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/1352
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
In an extruder for producing a polytetrafluoroethylene tube having a minimum thickness deviation by extruding a polytetrafluoroethylene paste through an annular portion formed by a core pin (30) and a die orifice (50) around it, the core pin comprises a mandrel connection end (34) which is connected to a mandrel and a die orifice outlet end (36) which is located at a die orifice outlet end, and the core pin has between the ends a portion of which cross-section perpendicular to an axial direction of the core pin has a smaller area than that of a cross-section of each end of the core pin. By using the extruder, the tube having a thickness deviation of not larger than 15% can be obtained.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.