EP 0317905 A2 19890531 - Method of drawing weldless tubes.
Title (en)
Method of drawing weldless tubes.
Title (de)
Verfahren zum Ziehen von nahtlosen Metallrohren.
Title (fr)
Procédé d'étirage des tuyaux métalliques sans soudure.
Publication
Application
Priority
- DE 3739730 A 19871124
- DE 3805838 A 19880225
Abstract (en)
[origin: JPH01202310A] PURPOSE: To automatically transport the next tubing to a die and to improve the efficiency of drawing by mutually fixing plural tubing, shifting a mandrel outside the action zone of the die during a joint is passed through the die and, after the joint is passed through the die, making the mandrel reach within range of the die. CONSTITUTION: The plural tubing are mutually connected before a drawing stage or in the midst of the stage. Then, the tubing 7a having the same dimension of cross section are supported above a bundle 7 of rings, the beginning and end of the bundle 7, 7a of the rings are connected. At the time of drawing, when the connected place 9 reaches within the range of the die 3, the mandrel 8 is shifted in the opposite direction to the drawing direction and does not act on the tube wall together with the die 3. Only the hollow drawing of the tubing 1 is executed and the reduction of wall thickness is not generated. The shift of the mandrel 8 is executed by providing ejecting parts 10, 11 at the front and rear ends of the tubing 1 and the mandrel 8 is automatically released. Next, after the connected place 9 is passed through the die, the mandrel 8 reaches within the action zone of the die 3 and the tubing is drawn.
Abstract (de)
Bei einem Verfahren zum Ziehen von Metallrohren (1) mit einem fliegenden Dorn (8) und einer Matrize (3) werden zwei oder mehr Rohrlängen vor dem Ziehen miteinander verbunden. Während des Durchtrittes der Verbindungsstelle (9) durch die Matrize wird der Dorn aus dem Wirkbereich der Matrize verlagert, so daß über eine bestimmte Länge des Rohr ohne Wanddickenverringerung gezogen wird. Der Dorn gelangt wieder in den Wirkbereich der Matrize, wenn die Ziehkraft an dem Rohr hinter der Verbindungsstelle angreift.
IPC 1-7
IPC 8 full level
B21C 1/00 (2006.01); B21C 1/22 (2006.01); B21C 1/24 (2006.01); B21C 1/30 (2006.01); B21C 1/32 (2006.01); B21C 3/16 (2006.01)
CPC (source: EP US)
B21C 1/24 (2013.01 - EP US)
Designated contracting state (EPC)
AT BE ES FR GB IT NL SE
DOCDB simple family (publication)
EP 0317905 A2 19890531; EP 0317905 A3 19891025; EP 0317905 B1 19920805; DE 3805838 A1 19890907; DE 3805838 C2 19970313; ES 2034123 T3 19930401; FI 885335 A0 19881117; FI 885335 A 19890525; FI 95542 B 19951115; FI 95542 C 19960226; JP 2672355 B2 19971105; JP H01202310 A 19890815; US 4856703 A 19890815
DOCDB simple family (application)
EP 88119170 A 19881118; DE 3805838 A 19880225; ES 88119170 T 19881118; FI 885335 A 19881117; JP 29482388 A 19881124; US 27558588 A 19881123