Method for cooling plastic film tube in blown film process
US9409340B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Oct 27, 2015 |
| Grant date | Aug 9, 2016 |
| Priority date | — |
| Expiry date | Oct 27, 2035 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29L2023/001
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
The present invention is directed to an apparatus for differential cooling of a plastic film tube. The apparatus and method includes the use of a blown film extrusion die that extrudes a plastic film tube upward. An air cooling system applies cooling air across one or more surfaces of the plastic film tube. One or more throttling valves are coupled to a pressurization pump that provides a pressurized working fluid, preferably water. The throttling valves are positioned to project the pressurized working fluid from outlets of the throttling valves towards circular arcs of the plastic film tube, the circular arcs of the plastic film tube being less than the circumference of the plastic film tube to provide a blown film tubular plastic film with controlled gauge variation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.