Effect of Refining Slag Phase Composition on Ladle Furnace Unit Lining Life1

FreeCutting Austenite Stainless Steel 303CuS2(%:≤0.08C,8.00~10.00Ni, 17.00~19.00Cr, 1.50~3.50Cu,0.24~0.35S) is smelted by 60t Electric Arc Furnace~60t Argon Oxygen Decarburization~60t Ladle Furnace~3 Flow continuous casting machine. With decreasing basicity of AOD refining slag from 2.0 to 1.6, controlling AOD tapping slag amount and tapping temperature, the [S] in AOD tapping steel increases to 0.008%~0.012% from original 0.004%~0.006%, after feeding S-wire containing 50% S and controlling the end temperature, the yield of S increases to 60%~70% from original 30%~50%, the qualified ratio of raises from 85% to 100%.

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Fundamental Research on Fluorine-Free Ladle Furnace Slag for Axle Steel of Electric Multiple Unit Vehicles

Metals ◽

10.3390/met11121973 ◽

2021 ◽

Vol 11 (12) ◽

pp. 1973

Author(s):

Qing Zhao ◽

Xiaohui Mei ◽

Lei Gao ◽

Jinwen Zhang ◽

Zhixiang Wang ◽

...

Keyword(s):

Laboratory Tests ◽

Composition Range ◽

Ladle Furnace ◽

Test Results ◽

Refining Slag ◽

Fundamental Research ◽

Multiple Unit ◽

Scale Test ◽

Main Components ◽

Furnace Slag

Fluorine-bearing refining slag (FBS) is used to produce axle steel for electric multiple unit vehicles. To avoid environmental pollution caused by fluorine, a fluorine-free ladle furnace slag (FFS) was designed based on an industrial FBS. The effects of main components on the physical and metallurgical properties of slag were investigated via theoretical analysis and laboratory tests. The composition range of components of the designed FFS are w(CaO) = 40–55 wt.%, w(SiO2) = 2–6 wt.%, w(Al2O3) = 30–40 wt.%, w(MgO) = 6–8 wt.%, and w(CaO)/w(Al2O3) = 1.25–1.50. Industrial-scale test results indicate that the FFS has similar deoxidation and desulfurization capabilities to industrial FBS.

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Effect of Na2O and Rb2O on Inclusion Removal in C96V Saw Wire Steels Using Low-Basicity LF (Ladle Furnace) Refining Slags

Metals ◽

10.3390/met8090691 ◽

2018 ◽

Vol 8 (9) ◽

pp. 691 ◽

Cited By ~ 4

Author(s):

Changyong Chen ◽

Zhouhua Jiang ◽

Yang Li ◽

Meng Sun ◽

Kui Chen ◽

...

Keyword(s):

Melting Zone ◽

Refining Process ◽

Ladle Furnace ◽

Refining Slag ◽

Dramatic Decrease ◽

Inclusion Removal ◽

Wire Steel ◽

Al2o3 Inclusion ◽

Lf Refining ◽

Slag Entrapment

Inclusion removal and modification of C96V saw wire steel using Na2O- and Rb2O- containing novel low-basicity LF (ladle furnace) Refining Slags have been researched. The results indicated that the addition of Na2O deteriorates inclusion removal; by contrast, the addition of Rb2O seems to significantly enhance inclusion removal. In detail, Rb2O can improve the cleanliness in the as-quenched C96V saw wire steel melts compared to preexisting synthetic LF refining slag compositions: (i) The average inclusion diameter experienced a remarkable decrease after reaction between the liquid steel and the synthetic LF refining slag; (ii) In addition, the number of inclusions also suffered from a dramatic decrease, with the reaction time increasing from 900 to 2700 s (15 to 45 min); (iii) Furthermore, both of the MnO-SiO2-Al2O3 and CaO-SiO2-Al2O3 inclusion system mainly concentrated in the low melting zone when the composition of Rb2O in synthetic refining slag was ≥5.0 wt%. This is mainly because Na2O significantly reduces the viscosity of refining slag, while Rb2O increases it. Then, there are two remarkable influences causing the increase of viscosity of refining slag with the addition of Rb2O: the inclusions can be sufficiently entrained within the slag once absorbed due to the significant increase in the viscosity; and the slag entrapment during refining process weakened dramatically.

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Study Results of the Electrical Parameters of the High-Power "Ladle-Furnace" Unit and its Impact on the Power Supply Network

Elektrichestvo ◽

10.24160/0013-5380-2021-3-33-43 ◽

2021 ◽

Vol 3 (3) ◽

pp. 33-43

Author(s):

Ivan N. APRELKOV ◽

Keyword(s):

Electric Power ◽

Power Quality ◽

Power Supply ◽

Electric Arc ◽

Furnace Unit ◽

Operating Conditions ◽

Ladle Furnace ◽

Supply Network ◽

Study Results ◽

Electric Power Quality

The steel refinement and its chemical composition and temperature finalization processes in a pouring ladle carried out by heating the metal with electric arc have received wide use at modern metallurgical enterprises. The article considers the electrical operating conditions of the ladle furnace unit (LFU) equipped with a 40 MVA electric furnace transformer. It was expected that the LFU load would vary insignificantly, because the electric arc burns between the electrodes and the surface of already molten metal, without the occurrence of short circuits. However, the accomplished studies testify that the LFU load is abruptly variable and nonlinear in nature, and gives rise to significant voltage fluctuations and harmonic distortions in the power supply network. The flicker intensity (severity) factor has been estimated, and the level of current harmonic components generated due to LFU operation has been determined. By using the obtained results, it becomes possible to predict the influence of LFU electric operating conditions on the levels of electric power quality indicators in changing the power supply network parameters, and to adopt circuit engineering solutions for assuring the electric power quality in the plant electric power supply system.

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