The nitrogen belongs to elements which have significant impact in steel mechanical properties. The influences of individual elements on the properties of solution of nitrogen in the metal bath, on ...the process of nitrogen dissolution in connection with decarburisation process and also influences of some important factors on the possibilities of nitrogen regulation during the refining period were investigated in this work. The path for production of steel with regulated nitrogen content relies on the combination of knowledge of nitrogen thermodynamics, mechanism and kinetics of nitrogen sorption and desorption, together with possibilities of steel melt properties prediction and also with metallurgical actions leading to the control of required chemical composition.
The steel desulphurization in ladle furnace depends on temperature, oxygen and sulphur content in the steel, but mainly on chemical composition and physical properties of slag. Necessary requirement ...for effective desulphurization is also minimum content of easily reducible oxides in the slag. There are many correlations for expression of slag desulphurization capability, where their functional dependency on each other can be found, mainly between sulphur distribution coefficient, optical basicity, basicity, sulphide capacity, desulphurisation potential of slag and also calcium - aluminate ratio of oxides in slag or content of easily reducible oxides in slag. This work presents statistical and graphical correlation between manganese and slag parameters using the set of approximately 768 heats and based on these, the optimal parameters for slag desulphurization capability are expressed especially for steel grades internally marked as OR1, OR3 in Železiarne Podbrezová, a.s. Steel grades OR1 and OR3 were chosen because of difference in manganese content with similar chemical composition of other elements. The MnO content in the slag is one of the most important parameters. Despite the higher scatter of obtained values, the distribution coefficient of sulphur (Ls) is one of the wide range of parameters for whom exists very close dependence on MnO content in slag.
Odsiarczanie stali zależy od temperatury, zawartości tlenu i siarki w stali, ale przede wszystkim od składu chemicznego i właściwości fizycznych żużla. Dla skutecznego odsiarczania konieczna jest również minimalna zawartość łatwo redukowalnych tlenków w żużlu. Istnieje wiele zależności do wyrażenia zdolności żużla do odsiarczania, dla których można znaleźć funkcyjną zależność pomiędzy współczynnikiem podziału siarki, optyczną zasadowością, zasadowością, zawartością siarczków, potencjałem odsiarczania żużla, a także stosunkiem tlenków wapnia do glinu w żużlu lub zawartością łatwo redukowalnych tlenków w żużlu. W pracy przedstawiono statystyczną i graficzną korelację pomiędzy zawartością manganu i parametrami żużla uzyskaną z około 768 wytopów, i na ich podstawie optymalne parametry zdolności żużla do odsiarczania przedstawione zostały dla stali wewnętrznie oznaczonych jako OR1, OR3 w Železiarne Podbrezová, a.s. Gatunki stali OR1 i OR3 zostały wybrane ze względu na różnice w zawartości manganu przy podobnej zawartości innych składników. Zawartość MnO w żużlu jest jednym z najważniejszych parametrów. Mimo większego rozrzutu uzyskanych wartości, współczynnik podziału siarki (Ls) jest jednym z wielu parametrów, dla których istnieje bardzo ścisła zależność od zawartości MnO w żużlu.
The metal properties upgrading applying its alloying with the simultaneous limitation of the impurities represents a prospective possibility of the metallurgical production further development. The ...interaction of the alloying substance active element with oxygen in metal and adjacent multiphase environment occurs under the actual conditions. Present paper is oriented particularly to the thermodynamic aspects of deoxygenation by titan in process of production of micro alloyed low carbon steel in two plants (oxygen converter 1-OC1 and 2-OC2) with the different effect of micro-alloy exploitation. Analysis of the effect of the metallurgical factors on the titan smelting loss in micro-alloyed steel production points at the need to master the metal preparation for the alloying and especially has got the decisive effect upon the oxidizing ability and rate of the slag phase availability. When comparing the micro-alloying matter yield among the individual production units, disclosed have been better results obtained in plant OC 2. Confirmed has been the effect of the slag amount (average amount of 7,3 t at OC 1 and 5,83 t at OC 2) and its quality during the steel tapping as one among the most significant factors affecting the alloying process and which also represent its oxidizing potential.
Metallurgical slag qualities must be defined by the whole complex of physico - chemical characteristics, such as an oxidative ability, optical basicity, sulphide capacity up to slag fluidity, its ...surface tension etc. The understanding of regulation of basic physico - chemical qualities of molten metals and slag depending on a chemical structure and a temperature has its importance at the level of the metallurgical process control. Presented paper deals with the possibilities how to exploit the sulphidic capacity for the desulphurisation evaluation in course of the metal reafining in the oxygen converter based on the set of the operational data. The integral part of the work is the process of the pig iron desulphurisation.
Present paper is oriented particularly to the thermodynamic aspects of deoxygenation by titan in process of production of micro alloyed low carbon steel in two plants (oxygen converter 1-OC1 and ...2-OC2) with the different effect of micro-alloy exploitation. Analysis of the effect of the metallurgical factors on the titan smelting loss in micro-alloyed steel production points at the need to master the metal preparation for the alloying and especially has got the decisive effect upon the oxidizing ability and rate of the slag phase availability. When comparing the micro-alloying matter yield among the individual production units, disclosed have been better results obtained in plant OC2. Confirmed has been the effect of the slag amount (average amount of 7,3t at OC1 and 5,83t at OC2) and its quality during the steel tapping as one among the most significant factors affecting the alloying process and which also represent its oxidizing potential.
Tundish metallurgy development, which has been focused on steel cleanliness improvement in last few years, affected also tundish slag systems. Molten slags are the most suitable for both absorbing ...and refining functions of tundish cover slags, while a system of extremely low density does satisfy their isolating functions in the best way. Hence it is obvious, that it is not possible to assure the main functions using one sort of tundish covering slags. In addition, traditional acid slags, are being replaced with basic covering slags, or combination of both types. In this work, we have tried to investigate the operation of tundish covering slag under the condition of slab continuous casting. A genesis of covering slag from applied cover powders its refining functions have been investigated, as well as the changes of covering slag chemical composition during one tundish casting sequence.
In continuous casting process, liquid steel flows through the tundish, which is supposed to operate as a continuous refining finisher. To provide a functionality of such a device, a pack of tundish ...metallurgy techniques must be applied, whose efficiency is conditioned especially with optimal symmetrical and dynamical melt flow. Flow optimizing can be achieved through the shaping of inside tundish configuration, using flow control devices such as turbulence inhibitors, impact pads, baffles, weirs, dams, etc. The theme of the present paper is the precise employment of a turbulence inhibitor, commercially known as TURBOSTOP, together with a pair of baffles & a flat impact pad in slab custer to improve steel cleanliness and a fluid flow phenomenon in a two strands tundish.
The result of the dynamic growth of the continuously cast steel ratio is the significant decrease in the waste from production in the metallurgical plants. The increasing significance of the metallic ...waste in the steel production under the conditions of 100% continuous casting in plant U.S. Steel Kosice and Iron works of Podbrezova, a.s., is not the typical case only for the Slovak metallurgical industry. It has the common feature which is the consequence of the scientific development of the metallurgical production in all industrially developed countries of the world.
The main characteristics of the casting powders for the continuous casting - their chemical composition, melting temperature, dynamic viscosity and specific consumption. Decisive factors of casting ...powders effect CC course. Effect of the casting powders properties on the cast products surface quality. Same field experiment results obtained with variety of casting powders application based on the domestic production (MOLDCAST). Evaluation of assimilation ability. Change of chemical composition of the CC casting powder in course of the casting. Ability of casting powders to absorb the alumina inclusions. Change of the physical and chemical parameters of the formed slag in course of casting. Analysis of the obtained information.
The metal properties upgrading applying it’s alloying with the simultaneous limitation of the impurities represents a prospective possibility of the metallurgical production further development. The ...interaction of the alloying substance active element with oxygen in metal and adjacent multiphase environment occurs under the actual conditions. Present paper is oriented particularly to the thermodynamic aspects of deoxygenation by titan in process of production of micro alloyed low carbon steel in two plants (oxygen converter 1-OC1 and 2-OC2) with the different effect of micro-alloy exploitation. Analysis of the effect of the metallurgical factors on the titan smelting loss in micro-alloyed steel production points at the need to master the metal preparation for the alloying and especially has got the decisive effect upon the oxidizing ability and rate of the slag phase availability. When comparing the micro-alloying matter yield among the individual production units, disclosed have been better results obtained in plant OC 2. Confirmed has been the effect of the slag amount (average amount of 7,3 t at OC 1 and 5,83 t at OC 2) and its quality during the steel tapping as one among the most significant factors affecting the alloying process and which also represent its oxidizing potential.
