Bleeder valve for pressurized furnace

The bleeder valve as claimed in claim l, wherein said closure member is dimensioned for sealing a conduit having an inner diameter of 400-1000 mm.

A shaft furnace, in particular a blast furnace, comprising a bleeder valve for controlling a gas outflow from the interior of said furnace to the ambient atmosphere through an exhaust conduit, said bleeder valve comprising:

• a valve seat associated with an exhaust conduit on said furnace;
• a movable closure member having a central closure surface and a peripheral sealing surface cooperating with said valve seat, said closure surface comprising a convex surface at least in proximity to said sealing surface;
• said closure member comprising a recurved deflection portion arranged at the periphery of said peripheral sealing surface, said recurved deflection portion comprising a deflection surface that is inclined against a tangent to said convex surface at the periphery of said convex surface by an angle in the range of 30° to 70° so as to impart to a gas outflow passing between said valve seat and said closure member a velocity component which is opposite to the initial opening movement of said closure member.

The furnace as claimed in 15, wherein said closure member is dimensioned for sealing a conduit having an inner diameter of 400-1000 mm.