Process and device for manufacturing hollow sections with end-side cross-sectional expansions

US6009734A · kind A · utility

Assignee

• Daimlerchrysler AG · US

Inventors

• Helmut Augustin · Hamburg, DE
• Henning Bloecker · Seevetal, DE
• Kai-Uwe Dudziak · Seevetal, DE
• Uwe Hardtke · Neu Wulmstorf, DE
• Carsten Rogowski · Hamburg, DE

Key dates

• Filing date: Nov 20, 1997
• Grant date: Jan 4, 2000
• Expiry date: Nov 20, 2017

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B21D26/047
• WIPO field: Machine tools
• WIPO sector: Mechanical engineering

Abstract

The invention relates to a process and apparatus for manufacturing hollow sections with cross-sectional expansions in end portions thereof. A hollow blank is widened and calibrated by internal high pressure forming by means of a forming tool receiving it, and, after the calibration, is separated in the area of the widening while forming two hollow sections with cross-sectionally widened ends facing one another in the separated position. In order manufacture from a hollow blank hollow sections with the lowest possible reject rate and therefore in a reliable process, which are cross-sectionally widened on the end side by means of high degree for forming, the blank is widened while the forming tool is open and is simultaneously upset to form a rotationally symmetrical bulging hollow section by means of a pressure force which is axially directed from the outside to at least one of the two blank ends.