摘要:
Disclosed is a continuous casting nozzle having a refractory portion formed to contain a dolomite clinker and arranged to define a surface region adapted to be in contact with molten steel, which is capable of protecting a working surface of the nozzle from alumina build-up due to alumina in molten steel, while improving corrosion resistance, even during long-term continuous casting of molten steel. The refractory portion is prepared by adding a binder to a mixed material and subjecting the obtained mixture to kneading, forming and heat treatment. The mixed material comprises a dolomite clinker which has an average particle size of 0.8 mm or less and a CaO content of 50 mass % or less. The mixed material has a ratio W1/W2 of 0.33 or more, wherein W1 is a content by mass of CaO, and W2 is a content by mass of MgO. The mixed material comprises a dolomite clinker and a magnesia clinker. Alternatively, the mixed material comprises a dolomite clinker and a magnesia clinker. The mixed material has a ratio WD/WM in the range of 0.5 to 15, wherein WD is a mass % of dolomite clinker particles having a particle size of 1 mm or less in a particle size distribution of the dolomite clinker, and WM is a mass % of magnesia clinker particles having a particle size of 1 mm or less in a particle size distribution of the magnesia clinker. Further, the mixed material has a ratio W1/W2 in the range of 0.33 to 3.0, wherein W1 is a content by mass % of a CaO component in the dolomite clinker, and W2 is a content by mass % of an MgO component in the magnesia clinker.
摘要:
A device for adjustably positioning a structural element in a dust-laden environment, such as for positioning impact casing elements in a metallurgical blast furnace, consists of a motion rod connected between a drive member and the elements to be positioned and a shield through which the motion rod extends, the shield is constructed of plates which form a slot and of a slide movably positioned in the slot and having a bore through which the motion rod extends. The slide covers an opening through the plates and forms a closure against the passage of dust into the drive member. Further, the bore surface through the slide is shaped to afford not only longitudinal movement of the motion rod but also limited pivotal movement and, in addition, the slide affords transverse movement.
摘要:
A forged copper burner enclosure capable of being mounted within the side wall of a steel melting furnace for the purpose of providing an improved cooling characteristic to a burner lance. The burner enclosure is provided with a central passage adapted to receive a burner lance for injecting oxygen into the batch of molten metal of an electric arc furnace. The forged burner enclosure is positioned such that only a solid forged copper face is on the furnace side when installed. The burner enclosure has an optional through hole which can be used for the purpose of treating the metal melt with particulate supply ranging from slag forming materials to metallurgical materials. The burner enclosure further has a number of coolant holes and tubes which provide a unique bidirectional flow of cooling fluid through each hole and increases cooling fluid velocity while reducing stalling and hot spots of the cooling fluid thereby providing better heat transfer and physical characteristics over cast or weld-assembled burner enclosures.
摘要:
A forged copper burner enclosure capable of being mounted within the side wall of a steel melting furnace for the purpose of providing an improved cooling characteristic to a burner lance. The burner enclosure is provided with a central passage adapted to receive a burner lance for injecting oxygen into the batch of molten metal of an electric arc furnace. The forged burner enclosure is positioned such that only a solid forged copper face is on the furnace side when installed. The burner enclosure has an optional through hole which can be used for the purpose of treating the metal melt with particulate supply ranging from slag forming materials to metallurgical materials. The burner enclosure further has a number of coolant holes and tubes which provide a unique bidirectional flow of cooling fluid through each hole and increases cooling fluid velocity while reducing stalling and hot spots of the cooling fluid thereby providing better heat transfer and physical characteristics over cast or weld-assembled burner enclosures.
摘要:
A rigid ceramic refractory base for a single-stack annealing furnace is assembled atop a base support structure utilizing a novel set of cast refractory segments, including a pair of C-shaped inner segments and four arcuate outer segments. Defined between the assembled inner and outer segments is a circular inner seal positioning trough that opens upwardly, and that has a tapered cross section that narrows with depth. A resilient but reinforced inner seal of novel form is installed in the trough utilizing upper and lower blankets of refractory fiber material that sandwich a plurality of elongate refractory fiber modules arranged end-to-end to circumferentially fill the trough. Each of the modules includes a serial array of compressed, cube-shaped blocks of fiber refractory material that are interspersed with thin, perforated metal members, with each of the arrays of fiber blocks and metal members being held together to form a module by metal rods that extend centrally therethrough and are welded to perforated metal members that cap opposite module ends. Arcuate steel structures that are assemblable to define an outer seal positioning trough are anchored to the cast refractory outer segments during their fabrication, and have end flanges that enable the cast refractory outer segments to be securely bolted together during assembly of the base. Associated methods of fabrication, assembly, use, maintenance, repair and replacement are disclosed.
摘要:
In a metallurgical furnace having a shaft heating section for use with sized material, an improvement wherein a plurality of projections is formed on the interior wall of the preheat zone of the furnace. The length of the projections is equal to 5 to 15% of the diameter of the shaft and the projections are spaced from each other a distance equal to two to ten times the length thereof. The projections may be formed as concentric rings around the interior wall of the preheat zone of the furnace or as a continuous helix formed on the interior wall. If desired, cooling tubes may be placed within the projections.