Process and equipment for treating crude iron outside the furnace

摘要

The invention relates to metallurgy and to the foundry field. The process comprises the treatment of molten crude iron, fed to a ladle, with a vacuum and modifying additives. The vacuum treatment of the melt is here carried out before the start of the interaction of the melt with the modifying additives and during this interaction, without interruption for 15 to 120 s. The equipment for carrying out the process according to the invention comprises a receiving vessel (1) with an outlet port (1b) closed by an insert (4), a ladle (2) arranged underneath the receiving vessel (1) and having a charging spigot (2a), and a vacuum chamber (3). The vacuum chamber (3) contains a branch (3a) for connecting the plant for evacuation of the air and is connected to the receiving vessel (1) and to the ladle (2) in such a way that a closed space, bounded by the walls of the vacuum chamber (3), is formed between these. The diameter of the outlet port (1b) is determined from the condition D = KV, where D is the diameter of the outlet port in mm, V is the volume of the melt to be treated in dm<3> and K is a proportionality factor amounting to 1.5 to 5. Modifications of the process and equipment are described. The process and equipment can be used for producing crude iron with a modified form of graphite - in the spheroidal form and vermiculite form. <IMAGE>