Process of forming a biaxially oriented thermoplastic tube including the formation and severance of a bubble forming a radially outwardly flared leading tube end
US4735538A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 22, 1986 |
| Grant date | Apr 5, 1988 |
| Priority date | — |
| Expiry date | Aug 22, 2006 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/1397
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A process of forming biaxially oriented tubular articles by repeatedly performing a cycle of operations which includes engaging a thermoplastic tube by a first clamping member over a first region at a trailing end of the tube and engaging the tube by a second clamping mechanism over a second region at a spacing from the first region so as to define between the clamping mechanisms a portion of the tube to be longitudinally stretched and radially expanded; moving the clamping mechanisms apart to stretch the tube portion therebetween longitudinally; admitting pressure fluid into the tube portion to expand it radially and form a biaxially oriented bubble adjacent the leading end of the tube, and severing a substantial part, but not all, of the bubble from the tube to form the tube with a radially outwardly flared end as the leading end of the tube for the succeeding cycle of operations.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.