Gfm Gesellschaft Fur Fertigungstechnik Und Maschinenbau

Gfm Gesellschaft Fur Fertigungstechnik Und Maschinenbau Gesellschaft

Hans Hojas

Bruno Kralowetz

Alois Leutgob

Johann Braunwieser

Johann Gsottbauer

The rolls of each rolling mill stand of a rolling mill train are driven by a hydraulic turbine. A variable displacement pump is operated to apply hydraulic pressure to each of said turbines to operate the same at an infinitely variable speed. Any change of said hydraulic pressure applied to the turbine which drives a preceding one of said stands in response to the initial passing of the stock through a succeeding one of said stands is detected. The displacement of the variable displacement pump which operates the turbine which drives said succeeding stand is adjusted to correct the speed of the turbine which drives said succeeding stand to compensate the change of the hydraulic pressure which has thus been detected.

Method of controlling the continuous movement of stock being rolled in a

First and second gripping heads consisting of a manipulator and a holder-up, respectively, are disposed on opposite sides of a swaging box. First and second sleeves are rotatably mounted in said first and second gripping heads, respectively and aligned on a horizontal axis which extends through said swaging box. A mandrel is non-rotatably and axially immovably mounted in said first sleeve and adapted to carry a tubular workpiece surrounding said mandrel. First and second abutments are carried by said first and second gripping sleeves, respectively, and have first and second annular gripping surfaces, respectively. Axial drive means serve to move said first gripping head along said horizontal axis toward said swaging box and to simultaneously move said second gripping head in the same direction. Control means serve to sense the magnitude of said gripping force exerted by said abutments with said first and second annular gripping surfaces and to detect any deviation of said magnitude from a set value and for controlling the movement of said second gripping head relative to said first gripping head along said horizontal axis in dependence on such deviation as said first and second gripping heads are simultaneously moved along said horizontal axis in said direction.

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Steyr, Austria

Hans Hojas