Abstract: In a method of producing heavy plate of steel, a prematerial is hot-rolled in several passes. As the prematerial at least two slabs of the same steel quality are superposed so as to form a pack and are welded by roll-bonding and reduced in thickness.

Abstract: In a method of producing heavy plate of steel, a prematerial is hot-rolled in several passes. As the prematerial at least two slabs of the same steel quality are superposed so as to form a pack and are welded by roll-bonding and reduced in thickness.

Abstract: In a method of and an apparatus for treating metal melts with flush gas during continuous casting, the molten metal is led from a tundish having an outflow opening into a mold, while inert flush gas is supplied above the outflow opening of the tundish at a rate of between 30 and 300 Nl per minute, so that the upwardly rising gas bubbles prevent slag particles present on the surface of the metal bath in the tundish from being sucked into the metal stream.

Abstract: In a method of continuously casting steel strands in continuous casting plants, casting powder admixed with at least one alloying component is continuously supplied to the casting level in the mould so that the alloying component is taken up by the strand surface.

Abstract: A process and an apparatus for continuously casting strands of unkilled or semi-killed steel having a product of [%C] .times. [%O] that is less than 0.002, preferably less than 0.0015 due to deoxidizing prior to casting, a carbon content of between 0.02 and 0.20%, an Al content not exceeding 0.01% and a Si content not exceeding 0.05%, wherein the steel is cast from a tundish through a casting tube that is immersed in the mould and flush gas is introduced into the casting tube and moved on together with the steel which leaves said casting tube via two lateral, upwardly inclined openings. The ascending gas bubbles are deflected by means of a guiding plate and move through a gap formed between said guiding plate and the walls of said mould, flushing out CO-bubbles forming at the front of solidification and thus providing for an edge zone that is free from blow-holes.

Abstract: A casting tube with a bottom opening for continuously casting steel strands, in particular billets with dimensions of 300 .times. 150 to 500 .times. 300 mm, comprising a converging-diverging end part forming a necking and at least two upwardly inclined lateral outlet openings thus providing for a controlled braking of the flow of steel in the mould. Advantageously, the cross-sectional reduction in the converging part to the necking is 30 to 70 %. The casting tube may be constructed in one piece and have, at its inflow-side, an opening for supplying flush gas.

Abstract: A method of continuously casting steel strands, in particular slabs in a continuous casting plant, involves the withdrawal of the strand from a cooled, oscillating mold and the further cooling of it in a secondary cooling zone arranged to follow the mold. The oscillation frequency of the mold and the lowering speed of the strand are coordinated with each other so that the distance between the oscillation marks, defined as the quotient of the lowering speed in m/min to the mold frequency in strokes/min, amounts to maximumly 0.018 m. The oscillation marks that occur on the strand surface constitute dangerous points of weakness which ultimately lead to the formation of cracks. By the method of the present invention it is possible to eliminate the crack formation altogether or at least to reduce said risk to a minimum.

Abstract: A method of determining the suitability of continuously cast slabs of Al- or Al-Si-killed soft steel for producing cold rolled sheets to be tinned, wherein from the cast strand a transverse sample of a length of 50 to 150 mm, preferably 100 mm, is taken by making parallel cuts perpendicular to the thickness of the strand, and a slanting cut is made from the one end of the sample starting from the surface thereof, which at the other end of the sample is 30 mm deep, whereupon a Baumann print is made of this cut area, which shows inclusion clouds as brown spots; upon this the whole area of the inclusion clouds is planimetered and the planimetered area in mm.sup.2 is put in relationship to the slanting cut area in dm.sup.2 ; a use of such steels having a characteristic value thus determined of maximally 5 mm.sup.2 /dm.sup.2.

Abstract: The present invention relates to a continuous steel casting method for a casting capacity of more than 1.5 metric tons of steel per minute. In this method a vertically arranged, substantially rectangular mold is used, into which at least one steel stream containing inert gas is passed through a casting tube below the surface of the casting level in the mold. The casting tube is provided with lateral downwardly inclined outlet openings, whose axes lie in a vertical plane running through the larger transverse axis of the mold. The axes of the lateral outlet openings run at an angle which depends upon the perpendicular distance of the axes from the narrow side of the mold. The inert gas is supplied in an amount of 1 to 15 Ncm.sup.3 /kg steel, preferably 3 to 8 Ncm.sup.3 /kg steel, to the steel stream over its entire cross section at the place of origin above the mold. The invention is of particular advantage for slabs wider than 800 mm of aluminum-containing steel.