Headbox device for a papermaking machine

US4906336A · kind A · utility

Assignee

• Sulzer-Escher Wyss GmbH · CH

Inventors

• Elmer Weisshuhn · Weingarten, DE
• Herbert Holik · Ravensburg, DE

Key dates

• Filing date: Jun 9, 1988
• Grant date: Mar 6, 1990
• Expiry date: Jun 9, 2008

Classification

• Technology area (CPC D): Textiles; Paper
• CPC primary: D21F1/02
• WIPO field: Textile and paper machines
• WIPO sector: Mechanical engineering

Abstract

A fiber stock suspension is directed from a guide device through the nozzle chamber of the headbox device and out of the slice opening thereof onto a papermaking machine. This nozzle chamber comprises at least two zones or sections. The first zone subsequent to the guide device possesses a relatively low convergence angle or low angle of wall inclination of the headbox device relative to the direction of flow of the fiber stock suspension. The other or second zone is positioned prior to or immediately upstream of the slice opening and possesses a substantially greater convergence angle or angle of wall inclination. In the first zone subsequent to the guide device, an improved flow stabilization or quieting of the flow of the fiber stock suspension occurs after the deflection of the fiber stock suspension and the creation of turbulence by the guide device. In the second zone prior to the slice opening the fiber stock suspension is strongly accelerated. This results in an improved quality of the formation of the paper web and the longitudinal and transverse strength of such paper web which is formed in the papermaking machine.