Sizing apparatus

US6050800A · kind A · utility

Assignees

• Vindex Tubemakers Pty. Limited · AU
• Uponor B.V. · NL

Inventors

• Peter Glanville Chapman · Fawn Drive, AU
• Allan K. Wallace · Hobart, AU
• Leslie Herbert Cowling · Salisbury, AU
• Eino Holso · Viskafors, SE
• Jyri Jarvenkyla · Viinijärvi, FI

Key dates

• Filing date: Mar 13, 1998
• Grant date: Apr 18, 2000
• Expiry date: Mar 13, 2018

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B29C48/912
• WIPO field: Other special machines
• WIPO sector: Mechanical engineering

Abstract

A sizing sleeve for controlling the diameter of plastic tube includes pressurized sizing sleeve portions in which fluid is injected under pressure about the tube circumference to form a lubricating layer. Drainage zones axially separate and isolate adjacent pressurized portions to allow independent temperature and pressure control. Each pressurized portion has flow stabilizer reducing variations in flow responsive to changes in the lubricating layer pressure. The flow stabilizer may comprise a high pressure fluid source and high pressure drop constrictor comprising fine apertures, which may be formed as grooves milled into end surface of abutting sizing sleeve segments.