An alumina-based filling sand for sliding nozzle comprising at least 50 wt % of mixed sand including 20 to 90 vol % of alumina sand and 80 to 10 vol % of silica sand, wherein the alumina sand has surface irregularities of 1.3 or less and comprises 50 wt % or more of an Al.sub.2O.sub.3 component.

A tap hole filling device for an electric arc furnace (1) includes a pivot arm (30) pivotable between a parking position and an operating position, a pivot arm actuator (40), an actuator link mechanism (50), and a refractory filling material dispenser (60) attached to an end portion (31) of the pivot arm to dispense refractory filling material (S) from a dispensing opening thereof while the pivot arm is in the operating position. The actuator link mechanism includes a connector (51) that is moveable between a connecting position, where the connector connects the pivot arm and the pivot arm actuator such that the pivot arm actuator (40) can pivot the pivot arm between the parking position and the operating position in an automatic operation mode, and a disconnected position, where the connector does not connect the pivot arm and the pivot arm actuator, to enable a manual operation mode.

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.

An apparatus for shaving a tap hole surface of a blast furnace or the like wherein efficiency can be improved, and a worker can be freed from physically burdensome work in the vicinity of the lower furnace wall of a blast furnace under high temperature. The apparatus includes a surface shaving unit having smoothing bits, and a rotating mechanism unit that, when the surface shaving unit is pressed against the tap hole surface, rotates the surface shaving unit, by utilizing the pressing force, by a predetermined angle in a predetermined direction substantially parallel to the surface, and holds the surface shaving unit at the rotated position. The rotating mechanism unit eliminates the need for work such that every time a conventional surface shaving unit is separated from the tap hole surface after being pressed against the surface, a worker manually rotates the surface shaving unit by a predetermined angle.

An alumina-based filling sand for sliding nozzle comprising at least 50 wt % of mixed sand including 20 to 90 vol % of alumina sand and 80 to 10 vol % of silica sand, wherein the alumina sand has surface irregularities of 1.3 or less and comprises 50 wt % or more of an Al.sub.2O.sub.3 component.

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.

An ignitor cap for a thermal lance including a proximal end adapted to receive the thermal lance, a distal end, a housing having a sidewall extending from the proximal end to the distal end and defining a passageway, and primary fuel and secondary fuel disposed within the passageway. At least a portion of the primary fuel is in contact with the secondary fuel and/or the distal end is substantially sealed and the proximal end includes at least one opening such that, when the thermal lance is received in the proximal end of the ignitor cap, gas flows axially through the primary fuel and the secondary fuel, and is then redirected by the sealed distal end back through the primary fuel and the secondary fuel and out through the at least one opening and along an exterior surface of the thermal lance. Also, thermal lances including such an ignitor cap.

A system and method for robotic tapping of rotating furnaces is provided.

The present invention attains the above-described objective by a robot that uses a coarse positioning system to align roughly with the tap hole and a fine positioning system using optical alignment for fine positioning before operating a tool for opening, maintaining or plugging the tap hole.

The present disclosure provides a cutting device. The cutting device includes a shaft, two or more gussets, two or more radial cutting members, and a circumferential cutting member. The shaft extends from a first end to a second end. The two or more gussets include at least a first gusset and a second gusset extending radially away from the shaft. The two or more radial cutting members include at least a first radial cutting member axially supported by the first gusset and a second radial cutting member axially supported by the second gusset. The circumferential cutting member is axially supported by each of the first gusset and the second gusset.

A method for manufacturing pig iron in an electrical smelting furnace including a vessel, the method including the following successive steps: loading DRI product in the vessel, melting the DRI product to form a pig iron layer topped by a slag layer, and injecting a desulphurizing reagent directly in the pig iron layer. It also deals with the manufacturing of steel from the pig iron and the associated electrical smelting furnace.