Abstract: A filler sand for a ladle tap hole valve contains 45 to 55 mass % of zircon sand, 30 to 40 mass % of chromite sand and 10 to 20 mass % of silica sand and is blended externally with 0.05 to 5 mass % of carbon black calculated based on the total amount of the sands; or contains 30 to 90 mass % of chromite sand and 10 to 70 mass % of silica sand and is optionally blended externally with 0.05 to 5 mass % of carbon black, wherein 95 mass % or more of the chromite sand consists of particles having diameters falling within a range of 150 to 850 &mgr;m, 60 mass % or more of the chromite sand consists of particles having diameters falling within a range of 212 to 600 &mgr;m, 95 mass % or more of the silica sand consists of particles having diameters falling within a range of 300 to 1180 &mgr;m, and 90 mass % or more of the silica sand consists of particles having diameters falling within a range of 600 to 1180 &mgr;m.

Abstract: A filler sand for a ladle tap hole valve contains 70 to 90 wt % of chromite sand and 10 to 30 wt % of silica sand and is blended externally with 0.05 to 5 wt % of carbon black calculated based on the total amount of the chromite sand and the silica sand; or contains 70 to 90 wt % of chromite sand and 10 to 30 wt % of silica sand, wherein the chromite sand has a particle diameter distribution such that 99% or more of the chromite sand consists of particles having diameters ranging from 150 to 850 &mgr;m and that 95% or more of the chromite sand consists of particles having diameters ranging from 200 to 600 &mgr;m, and the silica sand has a particle diameter distribution such that 95% or more of the silica sand consists of particles having diameters ranging from 150 to 850 &mgr;m and that 80% or more of the silica sand consists of particles having diameters ranging from 200 to 600 &mgr;m.

Abstract: A filler for a sliding gate containing 70 to 90 wt % of chromite sand and 10 to 30 wt % of silica sand in which the particle size distribution of the chromite sand is substantially from 500 to 1,000 .mu.m, which is not melted, sintered or penetrated by molten metal (molten steel) poured in a ladle in a steel works, and therefore is easily discharged to let the gate through.

Abstract: A method for continuous casting of a slab comprises feeding molten steel into a mold through exit ports of an immersion nozzle and controlling a stream of the molten steel by means of an electromagnetic stirrer having a linearly shifting magnetic field. The direction of the linearly shifting magnetic field is toward the immersion nozzle, which is positioned at the center of the mold from a pair of narrow sides of the mold. A first frequency control step controls a frequency of a wave of the shifting magnetic field to be higher than a threshold frequency, wherein the wave has a period equal to the time during which the stream of the molten steel poured from the immersion nozzle passes through an area to which the linearly shifting magnetic field is introduced, said area having an upper limit and a lower limit.

Abstract: A claw crane well suited for loading and unloading, transporting and stacking steel products such as blooms, includes a mast suspended from the crane proper to be moved vertically, a beam tiltably attached to the lower end of the mast, and a plurality of load carrying claw shifters and load unloading pusher means which are movably arranged on the beam.