Experience of application of calcium-containing cored wire with various fillers at steel ladle treatment

2021 ◽  
Vol 77 (4) ◽  
pp. 432-444
Author(s):  
A. D. Khoroshilov ◽  
P. A. Salikhanov ◽  
D. P. Byzov ◽  
M. V. Zhironkin ◽  
K. B. Bikin
Keyword(s):  
Ladle Treatment ◽  
Steel Ladle ◽  
Cored Wire

Experience of thick-walled calcium-containing cored wire application at steel ladle treatment

2021 ◽  
Vol 77 (9) ◽  
pp. 1020-1023
Author(s):  
M. K. Isaev ◽  
V. A. Bigeev ◽  
A. B. Sychkov ◽  
A. M/ Stolyarov
Keyword(s):  
Liquid Steel ◽  
Calcium Content ◽  
Efficiency Index ◽  
Ladle Treatment ◽  
Steel Shell ◽  
Steel Ladle ◽  
Recovery Coefficient ◽  
Cored Wire ◽  
Wire Feeding ◽  
Cored Wires

Metal processing in ladle by calcium-containing cored wires is one of the most spread methods of ladle treatment and modifying. Results of analysis of efficiency induces of existing cored wires application depending on their diameter, wall thickness and filling coefficient presented. It was shown that the basic efficiency index of a cored wire application – recovery coefficient – depending on wire quality (homogeneity of filling by calcium along the wire length), wire grade, conditions of its injection into liquid steel and other parameters can vary within a range from 50 to 95%. Reasons of unsatisfactory calcium recovery at usage of calcium-containing wires of 14–15 mm diameter with steel shell 0.4 mm thick and filling of mechanical mixture of steel shots and metallic calcium in various proportions was considered. Advantages of the modern calcium-containing cored wire with thicker wall were highlighted, including their higher wire rigidity and stability of its supply by a wire feeder into liquid steel. It was established that calcium content in a cored wire at the level of 100 g/m was the most effective composition. It was noted that increase of speed of cored wire feeding into steel will result in an increase of calcium recovery and in a decrease of probability of metal splashing out the steel ladle.

Study of effect of wheel steel microalloying by calcium and barium on nonmetallic inclusions modification

2020 ◽  
Vol 76 (6) ◽  
pp. 564-572
Author(s):  
A. V. Gaivoronoskii ◽  
N. V. Pavlova
Keyword(s):  
Service Life ◽  
High Speed ◽  
Nonmetallic Inclusions ◽  
Ladle Treatment ◽  
Wheel Steel ◽  
Rolling Stock ◽  
Steel Ladle ◽  
Treatment Technology ◽  
Cored Wire ◽  
Globular Form

The increase in freight cars axis loads, dynamic loads and heat impact on the wheels, change of other factors, stipulated by railway transport traffic intensification lead to considerable decrease of service life of solid-rolled wheels. To increase the service life of them, provision of the transport metal purity in non-deformed oxide nonmetallic inclusions with high content of Al2O3, decrease of general steel pollution by nonmetallic inclusions by micro-alloying and modification is an actual task. The purpose of the study was elaboration of wheel steel ladle treatment technology, including the steel micro-alloying and modification by barium-containing alloys to create material, which could meet high operation requirements, made to the railway wheels of new generation, intended to operate under increased axis loads conditions at the modern high-speed rolling-stock. It was shown, that replacement of everywhere applied silicocalcium by barium-based alloys is one of perspective ways of modification mechanism perfection. Results of industrial tests of micro-alloying of wheel steel by barium during ladle treatment presented. It was shown, that application for modification of cored wire with silicobarium filler instead of cored wire with silicocalsium filler СК-30, enabled to transform the nonmetallic inclusions into globular form practically completely, to raise the steel purity for all kinds of inclusions in both middle and maximum points range and to refine to some extent the grain size by 1-2 points. In the pilot metal at the depth of 40 mm from the surface, the gain was somewhat finer and more uniform (number 7), comparing with the existing technology (number 5-6). The pollution of the pilot metal by nonmetallic inclusions meets requirements of GOST 10791—2011 for category A and those of the standard EN 13262: 2004+А2:2011 for category 1.

scholarly journals Technical and economic aspects of development and running ladle treatment aggregates

2019 ◽  
Vol 75 (8) ◽  
pp. 985-990
Author(s):  
A. V. Protasov
Keyword(s):  
Production Capacity ◽  
Ladle Treatment ◽  
Steel Ladle ◽  
Cored Wire ◽  
Refining Operation ◽  
Narrow Temperature Interval ◽  
Steel Grades ◽  
Steel Refining ◽  
Metal Products ◽  
Globular Form

Modern ladle treatment of liquid steel represents a wide set of technological processes and aggregates, as well as units and systems, many of them having significant cost and need expensive maintenance. Technical and economic advantages, obtained at various variants of steel ladle treatment considered, the advantages being at both metal products producers and consumers. Factors of production expenses saving at the stage of steel smelting due to transferring of the steel refining operation from melting aggregates to the stage of ladle treatment considered. It was noted, that in the process of continuous casting of metal, subjected to ladle refining, the steel casting improves considerably due to keeping the narrow temperature interval, decreased content and globular form of nonmetallic inclusions. In its turn it results in a decrease of rejects, an increase of billet drawing speed possibility and correspondent increase of production capacity, reduction of the number of the casted billet shell breaks. Technical and economic advantages of melt treatment by cored wire or by all-metal injection wire with stuff shown. Decrease of rejects is an important factor for cost decreasing. For example, application of calcium-aluminum cored wire at a steel-works enabled to decrease the rejects of well-casings made of 20ГЮ steel by a factor of 1.5–2. In many cases production of state-of-the-art steel grades, for example IF-steels, being the base of the modern motor-car construction, is not possible without ladle treatment. Therefore, absence of ladle treatment elements at a big steelworks can lead to considerable losses.

scholarly journals Effective Materials from Recycled Aluminum Waste for Steel Ladle Treatment

2020 ◽  
Vol 718 ◽  
pp. 012019
Author(s):  
L V Tribushevskiy ◽  
G A Rumyantseva ◽  
B M Nemenenok
Keyword(s):  
Ladle Treatment ◽  
Steel Ladle

scholarly journals Efficiency evaluation of physical and chemical methods of steel quality improvement

2019 ◽  
Vol 75 (6) ◽  
pp. 695-705
Author(s):  
V. A. Golubtsov ◽  
I. V. Bakin ◽  
A. A. Tokarev ◽  
I. V. Ryabchikov ◽  
G. G. Mikhailov
Keyword(s):  
Quality Improvement ◽  
Liquid Metal ◽  
Ladle Treatment ◽  
Steel Ladle ◽  
Chemical Methods ◽  
Steel Quality ◽  
Wide Range ◽  
Metal Treatment ◽  
Metal Products ◽  
Physical And Chemical

To achieve a high quality of steel a wide range of liquid metal treatment methods applied. The choice of method is often determined by technological possibilities of the metal products manufacturer. An analysis of various physical and chemical methods of steel quality improvement accomplished, which allowed making a choice of liquid metal treatment method, depending on existing tasks and technological possibilities. It was shown, that physical and chemical methods of metal products quality improvement apart from other methods of ladle treatment have additional possibilities to effect steel quality. In some cases, those methods allow to exclude a complicated technological equipment, to reduce considerably expenses for liquid metal ladle treatment and to improve the products quality. A comparative analysis of methods of steel ladle treatment accomplished. Data on the active elements behavior in the iron based melts quoted. The mechanism of modification, inoculation and steel micro-alloying processes described. Data on industrial application those processes to obtain quality metal products quoted. It was shown, that melt modification process allows changing the metal structure, decreasing its impurity by nonmetallic inclusions, to change the nature, form and character of their distribution in the metal. Effect of the micro-alloying has a long-term and stable character of alloying elements impact and allows effecting the steel quality, changing steel chemical and phase compositions. Inoculation allows considerable increasing the ability of nuclei formation and effect the metal crystallization parameters due to formation of ready crystallization centers in the solidifying alloy. Base on analysis results a conclusion made, that physical and chemical methods of impact on steel allow purposefully effecting the metal products properties, reduce the cost of metal treatment and increase its quality.

scholarly journals Peculiarities of electric arcs heat recovery at semi-product heating in the EAF working space during finishing period

2019 ◽  
Vol 75 (6) ◽  
pp. 706-710
Author(s):  
A. V. Sazonov ◽  
E. E. Merker ◽  
A. A. Kozhukhov
Keyword(s):  
Heat Recovery ◽  
Ladle Treatment ◽  
Steel Ladle ◽  
Electric Arcs ◽  
Working Space ◽  
Automation Systems ◽  
Minimum Residual ◽  
Process Documentation ◽  
The One ◽  
Furnace Slag

Analytical calculations carried out to determine the degree of heat recovery by a liquid melt depending on the electric mode and the residual height of the furnace slag. It was shown that despite the use of automation systems, the temperature semiproduct tapping does not always correspond to the one specified in the process documentation. In this regard, there is a period of “finishing”, which is carried out at lower voltage steps and with a minimum residual mass of slag on the surface of the melt. An increase in slag mass leads to a decrease in the “freeboard” value in the steel ladle after tapping, which, in consequence, can lead to its downloading during ladle treatment procedure, with the loss of expensive additional materials. Based on the analysis of the data obtained, options proposed for improving the degree of heat recovery of electric arcs during the “finishing” period by changing the electrical parameters at a fixed height of residual slag in the furnace.

Application of microcrystalline complex modifiers for steel ladle treatment. Part 1. The role of nonmetallic inclusions in steel quality forming

2021 ◽  
Vol 77 (3) ◽  
pp. 295-309
Author(s):  
V. A. Golubtsov ◽  
I. V. Ryabchikov ◽  
I. V. Bakin ◽  
A. Ya. Dynin ◽  
O. N. Romanov ◽  
...  
Keyword(s):  
Liquid Metal ◽  
Nonmetallic Inclusions ◽  
Steel Production ◽  
Good Alternative ◽  
Ladle Treatment ◽  
Steel Ladle ◽  
Long Time ◽  
Negative Effect ◽  
Favorable Conditions ◽  
Inclusions In Steel

Contamination of steel by nonmetallic inclusions (NI) has a negative effect on mechanical characteristics of metal used under no favorable conditions. Conditions of NI forming in the process of steel smelting, ladle treatment and casting considered. It was shown that it is impossible to get rid of many NI. However, the task of forming less “harmful” NI having minimal effect on the decrease of finished products indices is quite practicable. To refine steel of NI it is reasonable to accomplish operations in a melt to modify NI morphology from dangerous acute-angled aluminous to globular oxide-sulphide. This task can be solved by introduction into metal complex modifiers comprising calcium, barium, strontium and rare earth metals. Addition of complex modifiers is a good alternative to complicative and long-time operations to decrease NI general content to lower levels, for example, by long-time metal ladle treatment. Application of the method enables in some situation to avoid expensive operations related to deep metal desulphuri zation and its dehydronization. Clean steel production becomes considerably easier at application of multicomponent alloys, obtained by a technology of accelerated crystallization. Application of such compositions results in forming globular oxide and oxide-sulphide compounds, as well as eutectics with low-melting point, which are comparatively quickly removed out of liquid metal. At that due to decreasing of liquation processes forming in the liquid metal, higher quality of large ingots and work-pieces, obtained from 420 t mass ingots can be reached.

A review of domestic and foreign experience of steel treatment in CCM tundishes

2020 ◽  
Vol 76 (12) ◽  
pp. 1230-1242
Author(s):  
A. V. Protasov ◽  
B. A. Sivak ◽  
L. A. Smirnov
Keyword(s):  
Nonmetallic Inclusions ◽  
Plasma Heating ◽  
Additional Treatment ◽  
Inert Gas ◽  
Steel Ladle ◽  
Cored Wire ◽  
Chemical Heating ◽  
Metal Treatment ◽  
Steel Treatment ◽  
Gas Supply

The modern steelmaking facilities melt as a rule a semi product, which is further subjected to various processes of refining in steel ladle. Recently an additional treatment of the metal in CCM tundish became widespread in the domestic and foreign practice. A tendency of transforming tundish into a multifunctional metallurgical reactor was noted, since more and more technological operations are transferred in it, including alloying, stirring, various methods of heating, modifying and removal of nonmetallic inclusions. Examples of comprehensive utilization of a bloom CCM tundish at some Japanese plants of Kobe Steel in Kakagava presnted, at which the metal is filtered when going through holes in the two partitions thus effectively removing nonmetallic inclusions. New variants of metal blowing off in the tundish by inert gas developed by domestic specialists considered, including a technology for metal blowing off by an inert gas and a facility for the inert gas supply through the stopper of the tundish. Supply of inert gas through the stopper results in efficiency increasing of degassing and nonmetallic inclusions removal as well as submerged nuzzles service time increase, which is particularly important at casting of steels with high content of aluminum. Examples of solutions of metal treatment in tundish by cored and aluminum wire given. Schemes of cored wire introduction into tundish and liquid steel treatment in a CCM mold considered. Considerable attention was given to the problem of metal temperature control in tundish, including by an electric arc, induction and plasma heating. List of domestic and foreign plants presented, implemented facilities of steel plasma heating in the CCM tundish. It was noted, that steel chemical heating in tundish can be applied at unforeseen problems arising at casting.

scholarly journals An alternative lining of steel ladles: technical and economic aspects

2018 ◽  
pp. 72-80
Author(s):  
L. M. Akselrod ◽  
V. Garten
Keyword(s):  
Phenol Formaldehyde ◽  
High Heat ◽  
Ladle Treatment ◽  
Ladle Lining ◽  
Concrete Lining ◽  
Steel Ladle ◽  
Refractory Materials ◽  
Metal Quality ◽  
Gaseous Hydrocarbon ◽  
Steel Making

Quality of steel ladles lining to a big extent determine the economic efficiency of steel-making operation. Direct costs on the refractory lining of them can reach 30–50 % of the costs of lining of a steel-making complex. Experience of utilization of refractory materials of different composition considered with the purpose of efficiency increase of refractory materials application in the steel ladles lining under conditions of steel ladle treatment. Considerable abilities shown to make the lining of steel ladle walls and bottom by both carbon-containing and carbon-free refractory materials taking into account the economic aspect. Lining base of steel-making facilities — BOFs, EAFs and steel ladles — is composed by periclase-carbon (MgO–C) refractories. However those refractories have a high heat conductivity, that effects on the heat operation of steel ladles. When using MgO–С materials, vertical fractures can appear in the ladle walls lining as its residual thickness becomes small. Under definite conditions a working lining chipping takes place, problems appear with lining destruction in the pieces angles with cavities formation at the pieces joining. To level the MgO–С drawbacks, periclase-alumo-carbon (MgO–Al2O3–С) and alumo-periclase-carbon (Al2O3–MgO–С) refractory products are used. Al2O3–MgO–C refractories are widely used in most erosion-intensive lining zone — in the combatting place of steel ladle bottom lining. In Russia monolithic lining of steel ladle bottom is successfully displacing the lining by piece products, including alumo-periclase-carbon ones. Such a replace enables to decrease specific refractory consumption and specific costs of them. At present the technology of concrete application to bottom is implemented for ladles of BOF- and steel-making shops. A technology of concrete ladle walls and bottom is intensively implemented for 120–180-ton ladles. The concrete lining of steel ladles has the following advantages: high withstandability against impregnation by metal-slag melt; absence of metal carbonization by the carbon from ladle lining; increase of running duration of safety lining layer by 2–2.5 times; absence of necessity to use nest blocks in both steel outlet unit and for bottom blow-off lance; absence of cracks in lining, wash-outs in seams, angles and edges of pieces; decrease of gaseous hydrocarbon emissions(phenol, formaldehyde, benzapilene) during lining drying, heating-up and operation (only slag belt remains, where pieces have organic binders); saving of materials, working time and manpower while making and maintain the lining; decrease of specific consumption and specific costs for lining per 1t of steel. For lining of steel ladles of big volumes (more 250 t) alumo-periclase (alumo-spinel) products are widely used in China, Europe and Japan. For such a lining the thermo-mechanical tension, arising in monolithic ladle lining, has a less importance, including at its replacing with metal by using crane. It is easier for the products to compensate the ladle geometry change, resulted in metal shall geometry change in time. A positive influence of carbon-free lining, as well as a lining with low content of magnesium oxide, on metal quality noted, first of all for low- and ultralow carbon grades, and pipe low-alloyed steels.

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