Global Patent Index - EP 0153495 B1

EP 0153495 B1 19880803 - METHOD OF DRAWING A SEAMLESS METAL TUBE

Title (en)

METHOD OF DRAWING A SEAMLESS METAL TUBE

Publication

EP 0153495 B1 19880803 (DE)

Application

EP 84116298 A 19841224

Priority

DE 3405641 A 19840217

Abstract (en)

[origin: EP0153495A2] 1. Method of drawing a seamless metal tube (1) in which a pressed and/or rolled metal tube (1) is reduced both in diameter and also in wall thickness by means of a plurality of successively arranged drawing dies (5, 9), floating mandrels (2a-2f) arranged within the tube (1) in the region of the drawing dies (5, 9) and driven traction members (6) positioned following the drawing dies (5, 9) in which the mandrels, which are arranged in sequence correlated to the dies (5, 9), are introduced together into the end of the length of tube to be drawn and are set to function in succession by the formation of depressions (21) in the metal tube, and the length of tube is provided with a necked-down region, characterised in that the necked-down region (4) is stepped, the number of steps (4a-4f) corresponds to the number of successively arranged drawing dies, and the diameters of the steps (4a-4f) in the same way decrease in accordance with the internal width of the successively arranged drawing dies (5, 9).

IPC 1-7

B21C 1/24

IPC 8 full level

B21C 1/24 (2006.01); B21C 5/00 (2006.01)

CPC (source: EP)

B21C 1/24 (2013.01); B21C 5/00 (2013.01); B21C 5/003 (2013.01)

Designated contracting state (EPC)

AT DE FR GB IT

DOCDB simple family (publication)

EP 0153495 A2 19850904; EP 0153495 A3 19860212; EP 0153495 B1 19880803; AT E36127 T1 19880815; DE 3405641 A1 19850822; DE 3405641 C2 19910725; DE 3473123 D1 19880908

DOCDB simple family (application)

EP 84116298 A 19841224; AT 84116298 T 19841224; DE 3405641 A 19840217; DE 3473123 T 19841224