The features of refractory lining’s wear of “ladle – furnace” unit at work on metallurgical mini-plant with intensive stirring of liquid metal by gas and electromagnetic field is studied. It was established that the most affected areas are slag zone, ladle’s bottom, as well as side wall, near which the electromagnetic stirrer is located. The stability of these areas determines the duration of the ladle working between repairs. Recommendations for recovery of the lining’s working layer have been developed. Also, there are formulated the requirements for rationalization of melt stirring modes. Theoretical studying of influence of electromagnetic stirring on heat & mass transfer processes in liquid metal bath of metallurgical aggregates (in particular, during homogenization of alloy in free turbulence mode at input of additives) was investigated. New electromagnetic stirrer was designed in the PTIMA NASU, and it is proposed for technologies of melting and finishing of alloys. The stirrer creates the pulsating magnetic field, and its force lines spread equally intensively both in the horizontal and vertical planes. It is shown that design of developed stirrer, its power supply by industrial frequency 50 Hz, and physical nature of the generated field’s action provide the simplicity of its making and operation. So, new stirrer has essential technical, economic and technological advantages in comparison with known stirrers of travelling magnetic field at the same parameters of electromagnetic systems. Joint research performed by specialists of the PTIMA NASU and IED NASU with using mathematical modeling and experiments on aluminum melt showed the following. It is possible to realize a wide range of stirring modes, both intensity and melt movement directions. Thus, the application of developed electromagnetic stirrer in the “ladle – furnace” units will allow to significantly expand the possibilities for finishing liquid alloys on chemical composition and temperature, especially at small metallurgical plants.

Based on the global trends in the metallurgy, the features of the further development of technologies for the cast metal productions are predicted. At the same time, there is considered the constant tightening of requirements for energy and resource saving, environmental and work safety, with the simultaneous need to improve the quality of casting, widening the range of obtained alloys and products from them. Also, ensuring reliable operation and expanding the functional capabilities of “ladle – furnace” units has particular importance, since they provide the complex out-of-furnace processing of melts, including averaging on temperature and chemical composition (at alloying and modifying too), removal gases and non-metallic inclusions, etc. It is noted that for the successful implementation of the listed technological operations, “ladle – furnace” units are equipped with additional devices and systems for heating the melt, vacuuming, blowing with inert gas (argon) and electromagnetic stirring. A comparative analysis of different methods of liquid metal stirring (by gas blowing and under the action of an external alternating electromagnetic field) showed that electromagnetic stirring is more effective and appropriate, especially at manufacturing relatively small batches of high-quality and special alloys on metallurgical mini- mills. At that, the most common at metallurgical enterprises and among research developments are electromagnetic stirrers of travelling magnetic field.There are indicated that applications of such stirrers have certain limitations due to physical characteristics. It relates to the need (in most cases) to supply them with a low frequency, making changes to the design of operating metallurgical aggregates for installation of the stirrer, as well as with not always rational hydrodynamic modes of melt stirring.The requirements concerning the development and application of electromagnetic stirrers for “ladle – furnace” units were formulated. Such devices should be simpler in design and operation, ensuring their long-term reliable working at obtaining a wide range of high-quality alloys. Keywords: “ladle – furnace” unit, metallic melt, gas blowing, electromagnetic stirring.

The using of the system of plasma heating of metal directly in the tundish is quite promising in terms of improving the technology of continuous casting of steel. At the same time, the efficiency of this technology is significantly influenced by the design of the tundish, the location of the plasmatron, the direction of movement of the circulation flows and their speed, the presence of forced mixing of the liquid metal bath, etc. In terms of design, the main technical solutions proposed for plasma heating of steel in a ladle are based on the creation of two-chamber tundish. Moreover, steel is heated in a special receiving chamber. Such heating devices are compact enough to be built into tundish without any significant modifications. Moreover, such heating devices practically do not reduce the useful volume of the tundish. The widespread use of the technology of plasma heating of metal in the tundish of the continuous casting machine (CCM) at a few metallurgical plants in the world is due to the need to increase the stability of the parameters of the casting process and improve the quality of the workpiece while simultaneously reducing specific energy costs. At the same time, additional prerequisites are created for the transformation of the tundish into a multifunctional unit for adjusting the steel temperature and the possibility of its refining. The using of plasma heating in the tundish is especially relevant in the conditions of mini-mills operating technological units of small capacity, for which the implementation of traditional highly efficient solutions for out-of-furnace processing, as well as processing on tundish-furnace units, is not always possible due to the complexity of organizing the heating process, large heat losses and high specific costs of refractories. In addition, such tundish can be quite effective when pouring high-quality grades of steel into billets of small cross-sections, which are produced, as a rule, in relatively small mixer-batches, which makes it difficult to prove them in small steel pouring ladles.