EP 0300262 B1 19920415 - METHOD OF DRAWING-OFF WORK FROM A BAR OR TUBE EXTRUSION PRESS, AND CONTROL SYSTEM OF A DRAWING-OFF DEVICE THEREFOR
Title (en)
METHOD OF DRAWING-OFF WORK FROM A BAR OR TUBE EXTRUSION PRESS, AND CONTROL SYSTEM OF A DRAWING-OFF DEVICE THEREFOR
Publication
Application
Priority
DE 3723824 A 19870718
Abstract (en)
[origin: EP0300262A1] The strand produced in a bar or tube extrusion press is drawn off with a controlled tensile force which keeps the emerging strand taut but should not influence the formation of the said strand. In order to keep constant the tensile force acting on the strand in the die zone, the procedure according to the invention is as follows: superimposed on this tensile force (draw-off force) matched to the cross-section and flow behaviour in the die is a tensile force (tractive force) which increases in proportion to the length of strand extruded and takes account of the weight per unit length and the coefficient of friction between the strand and the run-out table. The particular method adopted for this purpose is as follows: after a strand has been cut off and removed from the die, the tractive force and the length of the strand delivered are measured and the tractive force divided by the strand length is input as the specific profile friction force to be multiplied by the strand length, the latter being determined by displacement measurement, when a subsequent strand of the same desired cross-section is extruded. Control is carried out as follows: the desired value determined and input for the tensile force exerted on the tip of the strand is, in addition to a value taking into account the resistance to motion of the carriage of the drawing-off device, as the first summand, and a strand cross-section-dependent base value of the draw-off force, as the second summand, an increasing value, the respective product of the result of continuous delivery path measurement and predetermined specific profile friction force between the emerging strand and the run-out table, as third summand, beginning with the grasping of the tip of the strand by the grippers of the drawing-off device. <IMAGE>
IPC 1-7
IPC 8 full level
B21C 35/02 (2006.01)
CPC (source: EP US)
B21C 35/02 (2013.01 - EP US)
Designated contracting state (EPC)
AT BE CH DE ES FR GB IT LI NL SE
DOCDB simple family (publication)
EP 0300262 A1 19890125; EP 0300262 B1 19920415; AT E74803 T1 19920515; DE 3723824 A1 19890126; DE 3870068 D1 19920521; JP H0323244 B2 19910328; JP S6431521 A 19890201; NO 883135 D0 19880714; NO 883135 L 19890119; US 4995253 A 19910226; WO 9313885 A1 19930722
DOCDB simple family (application)
EP 88110678 A 19880705; AT 88110678 T 19880705; DE 3723824 A 19870718; DE 3870068 T 19880705; DE 8800439 W 19880718; JP 17282588 A 19880713; NO 883135 A 19880714; US 32780989 A 19890317