Device for inserting a lance into a pressurized container, in particular a blast furnace

A device for equipping an opening in a pressurized container for the axial insertion of a lance, the device comprising:

• a leaktight casing including:
• a first plate intended to be connected to a pressurized container and a second plate spaced from said first plate;
• a first through opening in said first plate and a second through opening in said second plate, each of said openings intended for passing therethrough a lance;
• sealing means attached to said second plate for establishing axial leaktightness around a lance when a lance is inserted therein;
• passage means in said leaktight casing between said first and second through openings for establishing a passage for a lance between said first and second through openings, said passage means having an axis and including;
• a first seat connected in a leaktight manner to said second through opening;
• a second seat being connected in a leaktight manner to said first through opening, said second seat being arranged opposite said first seat along said axis and being movable along said axis with respect to said first seat;
• closure means mounted in the leaktight casing for opening and closing said passage means between said first and second seats, said closure means being movable between a first position in which said closure means is aligned between said first seat and said second seat and a second position in which said closure means is outside of said first and second seats;
• means for moving said closure means between said first and second positions;
• first spring means for urging said closure means toward said second seat when said closure element is in its first position;
• second spring means connected to said second seat to move said second seat towards said first seat whereby said second seat can urge said closure element, against the action of said first spring means, toward said first seat when said closure means is in its first position;
• and
• actuator means connected to said second seat to move said second seat, against the action of said second spring means, away from said first seat into a retracted position in which said second seat is axially spaced from said closure element.