Method of and an apparatus for manufacturing elongated curved tubular elements

US4135380A · kind A · utility

Assignee

• Benteler-Werke AG · DE

Inventors

• Egon Olszewski · Paderborn, DE
• Eckehard Hanert · Schloß Holte-Stukenbrock, DE

Key dates

• Filing date: Sep 22, 1977
• Grant date: Jan 23, 1979
• Expiry date: Sep 22, 1997

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B21D11/18
• WIPO field: Machine tools
• WIPO sector: Mechanical engineering

Abstract

An apparatus for manufacturing elongated curved tubular elements sequentially clamps longitudinally spaced end portions of a straight elongated tubular section, confines a central portion of the tubular section intermediate the clamped end portions between two dies, applies forces to at least one of the dies to displace the same and thus also the central portion of the tubular section in a predetermined direction and to a given extent with respect to the clamped end portions so that substantially S-shaped transitory portions of deformed cross-sectional shapes develop between the clamped end portions and the central portion of the tubular section, and restores the cross-sectional shapes of the transitory portions preparatory to sequential retraction of the dies and unclamping of the end portions of the tubular section by means of at least one mandrel which is introducible into the tubular section through at least one of the end portions thereof for passage into and through at least one of the transitory portions of the tubular section.