Stopper control device

An apparatus comprising:

• a vessel for molten, steel including a drain hole for, an outflow of said molten steel,
• a stopper working on said drain hole to adjust said outflow,
• a control device for said stopper comprising:
• a frame,
• a control rod sliding through said frame, and rigidly attachable to said stopper,
• a hydraulic circuit including a double-acting hydraulic cylinder and a reversible hydraulic pump, said double-acting hydraulic cylinder having a first chamber and a second chamber between which a piston slides, said reversible hydraulic, pump being connected to said first chamber and second chamber in such a way that a rotation of the reversible pump in one sense of rotation sends fluid directly to the first chamber, thus determining a movement of the piston in a first direction and a rotation of the reversible pump in the other sense of rotation sends fluid directly to the second chamber, thus determining a movement of the piston in a second direction opposite the first direction, said piston being attached to said control rod,
• a control circuit connected, to said hydraulic circuit to control a position of said piston, characterized in that said reversible hydraulic pump is directly connected to said first chamber and second chamber of said doable-acting hydraulic cylinder, respectively by means of a first branch and a second branch of said hydraulic circuit wherein said hydraulic circuit and pump are entirely housed in said containing frame.