Sms Demag Ag

Mannesmann Aktiengesellschaft

Peter Kalkenings

Horst Stinnertz

Erling Roller

Karl H Hausler

Herbert Berendes

Method of producing welded Cu and Cu alloy pipes

A cold pilger rolling tool for producing internally ribbed tubes uses a cold pilger step rolling process in a rolling stand that is movable back and forth in a direction of rolling and has rolls of a tapered design. The rolls of the stand roll along a material with an alternating direction of rotation. The tool includes a cold pilger rolling mandrel which tapers. The tool further comprises an extension plug mounted coaxially and rotatably at a free end of the cold pilger rolling mandrel and in which a negative of the helical internal ribbing which is to be produced is machined.

Cold pilger rolling tool for producing internally ribbed tubes

A process for drawing stretched metal workpieces, especially tubes, for the purpose of cross-sectional reduction in more than one drawing step using at least two sequential drawing aggregates. The aggregates grip the workpiece on the outer periphery, with two alternately-moved clamping carriages, which draw the workpiece continuously through respective drawing rings associated with the respective aggregates and arranged in respective drawing-ring holders. The drawing aggregates can be driven independently of one another in a power-regulated and/or moment-regulated manner. Furthermore, during the drawing process, a defined prestress force, which prevents deflection of the workpieces from a straight line, is maintained at all times in the section of the workpiece located between the drawing aggregates.

Process and device for straight-drawing long drawing material in

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Aachen, Germany

Peter Kalkenings