EP 0283484 B1 19901122 - EXPANDIBLE MANDREL FOR TUBE-DRAWING MACHINE
Title (en)
EXPANDIBLE MANDREL FOR TUBE-DRAWING MACHINE
Publication
Application
Priority
EP 8600531 W 19860916
Abstract (en)
[origin: WO8801915A1] This expandible mandrel can grip unformed tubes (1) upstream of the drawing die (2) in order to draw them through the latter. A drawing train consisting of two draw-bars (37) is inserted in the closed position, into the end of the tube passing through the drawing die. The draw-bars are then opened out until expanding jaws (38) inside grip the tube wall by force. The expansion is effected by means of double wedges (35) which are pushed between the draw-bars by means of an axial rod (34). Said bars are mounted in an exchangeable and a pivoting manner in a housing by means of axial bolts (40). The bars are prolonged on the housing side by plates, on which are fixed jacks (41) facing said bars. In the rear position of the rod, i.e. when the double wedges are expanded, wedges (42) press on the rod side against the jacks, which causes the return movement of the expansion elements. In order to support, on the outside, the tube to be drawn, an axially movable ring (43) is envisaged in the expansion region, said ring being provided with a tapered support surface.
IPC 1-7
IPC 8 full level
CPC (source: EP)
Designated contracting state (EPC)
AT DE FR GB SE
DOCDB simple family (publication)
WO 8801915 A1 19880324; EP 0283484 A1 19880928; EP 0283484 B1 19901122
DOCDB simple family (application)
EP 8700502 W 19870905; EP 87905749 A 19870905