Abstract: A control device for a twin-roll continuous caster, comprising a plurality of maps, each of which teaches a relationship between a thickness of a cast strip and a roll separating force under a fixed casting speed, and teaches stable casting conditions under which bulging and surface cracks do not occur. The device detects a cast thickness and a height of the molten pool and selects an appropriate map from among the plurality of maps, by the detected height, and controls the casting conditions such that a target thickness of the cast strip is obtained under stable casting conditions by using the selected map.

Abstract: A cooling drum for continuous-casting machines, for manufacturing thin metallic strips, and having a surface composing part of a casting mold wall in contact with molten metal, wherein the surface has numerous dimples disposed uniformly thereon and not in contact with each other, and each of the dimples has an opening portion in the form of a circle or an oval with a diameter of from 0.1 to 1.2 mm and a depth of from 5 to 100 .mu.m.

Abstract: There is provided a process for producing a high-manganese iron alloy from a manganese ore and/or a pre-reduced product thereof in a top and bottom blown converter type reaction vessel holding molten iron or a molten manganese iron alloy, together with a molten slag, said molten iron or alloy and said molten slag being the products of a separate smelting furnace, gas being blown into said vessel through a bottom blowing nozzle, said process comprising charging said vessel with a supply of raw materials including at least one source of manganese and iron selected from a manganese ore containing manganese oxide and iron oxide and a pre-reduced product thereof, a solid carbonaceous substance and a slag forming agent, while simultaneously blowing gas selected from oxygen and a gas containing oxygen into said vessel through a top blowing lance to burn said carbonaceous substance so as to heat, melt and reduce said raw materials to form a melt containing manganese oxide and iron oxide; supplying an additional carbo

Abstract: A carbon-unsaturated molten metal or molten alloy containing elements more oxidizable than iron such as chromium and silicon is dephosphorized by addition of a flux composition comprising calcium carbide and a halide of alkali earth metal such as calcium fluoride in a non-oxidizing atmosphere, and thereafter the slag as a by-product is stabilized against formation of undesirable gases. This method when employed in refining ferrochromium or crude stainless steel makes feasible dephosphorization, and it is particularly suited for economical production of low phosphorus stainless steel.

Abstract: A quicklime is treated by CO.sub.2 gas so as to form a CaCO.sub.3 film on the surface of the particle thereof. It serves to prevent moisture absorption so that a steel making process, especially for the production of low hydrogen steel, can be done very effectively with low cost by the use of this CO.sub.2 -treated lime.