METHOD AND INSTALLATION FOR MANUFACTURE OF LARGE DIAMETER INGOTS Russian patent published in 2018 - IPC B22D11/04 

FIELD: metallurgy.

SUBSTANCE: invention relates to metallurgy. When casting metal ingots longer than 5 meters in short crystallizer (4), after reaching a predetermined length, the non-solidified part of the metal is heated. For heating, the metal melt is added in an amount that compensates, at least, the shrinkage of the metallic melt that occurs when ingot solidifies (6). In this case, the melt is introduced at a rate lower than the casting speed by a factor of 10, which is incrementally or continuously reduced to the end of the solidification of the ingot to 10 % of the initial refilling speed. Either the liquid metal mirror in the crystallizer is covered with a layer of liquid slag and heated by an electroslag method until the entire cross-section of the ingot solidifies. In this case, the melting rate of the consumable electrode (18) at the beginning of the heating process is set at a value of 0.5–2.5 of the ingot diameter or side length of the square ingots or half the sum of the narrow and wide sides of the rectangular ingots. Rate of melting of the consumable electrode at the end of refilling is continuously or step by step reduced to 10–15 % of the initial value.

EFFECT: quality of the ingot is improved.

10 cl, 5 dwg