A tap hole plug gun comprising a material chamber for receiving a plugging compound and a mouthpiece for being placed on a tap hole, the mouthpiece being connected to a nozzle part disposed on the material chamber by means of an unlockable connection device. The connection device is realized as a hinged joint arrangement, the hinged joint arrangement having two opposite hinged joints each having a joint bolt which can be removed from the connection to a joint plate arrangement.

A tap hole plug gun comprising a material chamber for receiving a plugging compound and a mouthpiece for being placed on a tap hole, the mouthpiece being connected to a nozzle part disposed on the material chamber by means of an unlockable connection device. The connection device is realized as a hinged joint arrangement, the hinged joint arrangement having two opposite hinged joints each having a joint bolt which can be removed from the connection to a joint plate arrangement.

A smelting vessel includes a plurality of heat pipes (21) positioned in a refractory lining of at least a part of the hearth (9) for cooling at least a part of the refractory lining. At least one of the heat pipes includes (a) a liquid phase of a heat transfer fluid, typically water, in a lower section of the heat pipe and (b) a vapor phase of the heat transfer fluid, typically steam, in an upper section of the heat pipe. The heat pipe also includes a vent to allow vapour phase to escape from the heat pipe to reduce the pressure or the temperature within the heat pipe when the vapour pressure or the temperature in the heat pipe exceeds a predetermined threshold pressure or temperature.

A smelting vessel includes a plurality of heat pipes (21) positioned in a refractory lining of at least a part of the hearth (9) for cooling at least a part of the refractory lining. At least one of the heat pipes includes (a) a liquid phase of a heat transfer fluid, typically water, in a lower section of the heat pipe and (b) a vapor phase of the heat transfer fluid, typically steam, in an upper section of the heat pipe. The heat pipe also includes a vent to allow vapour phase to escape from the heat pipe to reduce the pressure or the temperature within the heat pipe when the vapour pressure or the temperature in the heat pipe exceeds a predetermined threshold pressure or temperature.

A tap hole plug gun comprising a material chamber for receiving a plugging compound, a mouthpiece for being introduced into a tap hole, and a nozzle part tapered in the direction of the mouthpiece and connected to the material chamber by means of an unlockable connection device. For realizing the connection device, the material chamber and the nozzle part have complementary axial connecting projections on two opposite axial connecting edges of a chamber wall of the material chamber and of a nozzle wall of the nozzle part.

A tap hole plug gun comprising a material chamber for receiving a plugging compound, a mouthpiece for being introduced into a tap hole, and a nozzle part tapered in the direction of the mouthpiece and connected to the material chamber by means of an unlockable connection device. For realizing the connection device, the material chamber and the nozzle part have complementary axial connecting projections on two opposite axial connecting edges of a chamber wall of the material chamber and of a nozzle wall of the nozzle part.

A method of heating up a furnace bottom and a burner lance used in the method are proposed. The method of heating up the furnace bottom includes a step of opening, in the tap hole, a burner lance insertion hole having a diameter larger than a diameter of the burner lance so as to penetrate into the furnace, a step of installing the burner lance in the opened burner lance insertion hole, a step of filling a gap between the installed burner lance and a furnace exterior side of the tap hole with a refractory, and a step of blowing in gas for heating into the furnace from the burner lance to heat up the furnace bottom.

A method of heating up a furnace bottom and a burner lance used in the method are proposed. The method of heating up the furnace bottom includes a step of opening, in the tap hole, a burner lance insertion hole having a diameter larger than a diameter of the burner lance so as to penetrate into the furnace, a step of installing the burner lance in the opened burner lance insertion hole, a step of filling a gap between the installed burner lance and a furnace exterior side of the tap hole with a refractory, and a step of blowing in gas for heating into the furnace from the burner lance to heat up the furnace bottom.

A hole-opening bit that can simplify an operation for opening a tap hole for installing a burner lance for raising the temperature of a furnace bottom of a blast furnace, which allows the blast furnace to be started up in a relatively short time after long-time blast stoppage or after a furnace cooling accident, by efficiently heating the furnace bottom, and a tap hole opening method using the hole-opening bit. A hole-opening bit used to open the tap hole in the furnace bottom of the blast furnace including chips on rear surfaces of a furnace drilling surface of the hole-opening bit such that outermost ends of the chips are located inside of an outermost end of the hole-opening bit.

A hole-opening bit that can simplify an operation for opening a tap hole for installing a burner lance for raising the temperature of a furnace bottom of a blast furnace, which allows the blast furnace to be started up in a relatively short time after long-time blast stoppage or after a furnace cooling accident, by efficiently heating the furnace bottom, and a tap hole opening method using the hole-opening bit. A hole-opening bit used to open the tap hole in the furnace bottom of the blast furnace including chips on rear surfaces of a furnace drilling surface of the hole-opening bit such that outermost ends of the chips are located inside of an outermost end of the hole-opening bit.