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Steelmaking 2019 Vol.35 Please wait a minute... For Selected: Download Citations EndNote Ris BibTeX Toggle Thumbnails Select Outlook on progress of steelmaking technology in transition period of Chinese steel industry Steelmaking    Accepted: 01 January 1900 Select Physical simulation on molten steel flow characteristics in the RH reactor with arched snorkels Steelmaking    Accepted: 01 January 1900 Select Mg treatment process for high carbon steel 82B Steelmaking    Accepted: 01 January 1900 Select Emission status and reduction measures of dioxins in EAF steelmaking Steelmaking    Accepted: 01 January 1900 Select Optimization of dual-purpose tundish flow control device Steelmaking    Accepted: 01 January 1900 Select Effects of containing calcined forsterite tundish materials on steel cleanliness Steelmaking    Accepted: 01 January 1900 Select Three dimensional thermo mechanical coupling analysis of billet continuous casting mould Steelmaking    Accepted: 01 January 1900 Select Physical and mathematical simulation of mold flow field in slab continuous casting Steelmaking    Accepted: 01 January 1900 Select Research on control technology of inclusions in case hardening steel Steelmaking    Accepted: 01 January 1900 Select Corner crack control technology for continuous casting strand Steelmaking    Accepted: 01 January 1900 Select Development and application of online quality determination system for continuous casting slab Steelmaking    Accepted: 01 January 1900 Select 38CrMoAl steel production practice with BOF→LF→VD→CC process Steelmaking    Accepted: 01 January 1900 Select Effect of high Mach number oxygen gun position on flow rate of 100t converter automatic steelmaking molten pool Steelmaking    2019, 35 (2): 1-10.   Abstract （95）            Knowledge map    Save A three-dimensional model of four-hole Laval lance nozzle and converter body was established by using numerical simulation and cold water simulation to verify each other, taking a 100 t steelmaking converter in a northern steel plant as a prototype. The influence of the change of lance level on molten steel flow velocity in molten pool and the impact effect of jet flow were simulated and studied. The results show that with the increase of lance position from 1.7 m to 2.5 m, the impact capacity of molten steel in molten pool decreases and the impact depth decreases. However, with the increase of gun position, the action area of oxygen jet on molten steel is increasing. The lance position of the high Mach number lance is between 1.6 m and 2.2 m, and the impact depth of the lance is moderate. The pool mixing effect is the best. At this time, the distribution of molten steel flow velocity in the radial direction of the pool is more uniform, and the high-speed zone accounts for a larger proportion, the mixing time is shorter, and the stirring effect of molten steel at the bottom of the pool is the best. Related Articles | Metrics Select Design and application of high efficiency and energy saving swirl oxygen lance nozzle Steelmaking    2019, 35 (2): 11-19.   Abstract （85）            Knowledge map    Save The design parameters of swirl oxygen lance nozzle are evaluated by cold gas jet experiment, which also provides a reasonable reference for the operation of converter oxygen lance. Based on the industrial test, the parameters of swirl oxygen lance nozzle are revised, and the optimum holes of swirl oxygen lance nozzle for 120 t and 150 t converter at Laigang are finally determined. The optimum nozzle angle is 13° and the swirl angle is 6.5°～7°. While giving full play to the superiority of the swirl oxygen lance in slagging and slag splashing, the serious problem of corrosion in molten pool is solved, which makes the swirl oxygen lance widely used in medium and large converters. Using this swirl lance nozzle, especially in the case of large scrap steel ratio, the slagging effect of converter process is obviously improved, the oxygen utilization rate is improved, and the blowing time can be effectively shortened by more than one minute. When slag splashing, the slag accumulation effect in the molten pool is remarkable, the slag splashing effect is obviously improved, and the converter service life is obviously promoted. Related Articles | Metrics Select End-point static prediction of BOF steelmaking based on unconstrained wavelet weightedtwin support vector regression Steelmaking    2019, 35 (2): 20-24.   Abstract （126）            Knowledge map    Save Converter steelmaking is an extremely complex physical and chemical reaction process，and the research on prediction model with intelligent method is a hot spot in recent years. Aiming at the end-point hit rate of carbon content and temperature，a new modeling method of static predictionwas proposed. Based on the traditional twin support vector regression，the wavelet weight matrix was introduced into the objective function. Then，the objective function was transformed to the unconstrained optimization problem，which improved the performance andcomputational efficiency of the algorithm.Finally，the datasets of 260t BOF were collected from some steel plant to establish the static prediction model. The experimental results showed that the end point carbon mass fraction (error±0.005%) and temperature (error±10℃) of the prediction model achieved a hit rate of 94% and 96%，respectively，and the double hit rate was 90%. Compared with the existing methods，the proposed prediction model achieved the optimal results，which could not only guide the actual production，but also was used for the mathematical modeling of other application background in metallurgical industry. Related Articles | Metrics Select Bottom argon blowing system optimization and industrial tests Steelmaking    2019, 35 (2): 25-29.   Abstract （158）            Knowledge map    Save A similar ratio of 1∶2 water model was used to study the influence of bottom argon blowing position and flow on mixing time in 100 t ladle. Machine oil was simulated as top slag to compare the area of steel exposed under different blowing position and flow, and numerical simulation was used to compare flow field behavior of molten steel under different blowing position, and find the optimal argon bottom blowing control mode for ladle. Furthermore, the test of optimized ladle was carried out in the steel plant. The results show that retaining a reasonable argon bottom blowing position and control technology have important influence on the floating removal of inclusion in the ladle. When argon blow holes are at the angle of 135, 0.6R far to center of ladle, the mixing time is shorter and steel exposed is smaller. Meanwhile, after ladle bottom argon blowing for a certain time, the T.O content in the ladle was decreased obviously and the nitrogen content was not increased. The T.O mass fraction in slabs ranged from (7～9)×10-6, which was significantly lower than that in slabs before optimization (average 13×10-6). The control of T.O content has improved significantly. Related Articles | Metrics Cited: Baidu(1) Select Industrial practice of new calcium wire in 120 t LF Steelmaking    2019, 35 (2): 30-33.   Abstract （123）            Knowledge map    Save A new seamless pure calcium wire was boldly used to replace solid core pure calcium wire in 120 t LF of Masteel, in order to solve the problems of unstable yield and serious slag spattering in calcium treatment. It was found that the melting time of the new calcium wire could be prolonged and penetrated into the depth of molten steel due to the coating of nano-silica powder as the intermediate layer through theoretical exploration, and the theoretical feeding speed of the new calcium wire was 1.65 m/s through theoretical calculation. It was found that the highest yield of the new calcium wire was 34.6 % when the feeding speed was 1.5 m/s, while the average yield of the original calcium wire was only 20.7 % through field tests. And the large size inclusions could be greatly reduced and the CaO-Al2O3 composite inclusions could be transformed into C12A7 with low melting point by feeding new calcium wire into molten steel, which could better guarantee the pourability of molten steel. Related Articles | Metrics Select Effect of RH desulphurization on inclusions in non oriented electrical steel Steelmaking    2019, 35 (2): 34-38.   Abstract （125）            Knowledge map    Save The effect of RH desulphurization on inclusions in non oriented electrical steel through conventional process (continuous casting + hot rolling) and CSP process has been studied in this paper. When the amount of CaO-CaF2 desulfurizer is 1～4 kg/t， the RH desulfurization rate is about 25 %. The high oxidation of final slag and low MI value are one of the reasons for the desulfurization effect. The RH of CSP process is deoxidized by “aluminium followed by silicon”. The inclusions are mainly AlN, MnS, CaS and a small amount of calcium aluminate. At this time, the total amount of inclusions is mainly affected by nitrogen content, and the sulfur content is proportional to the density of sulfide inclusions. The RH of conventional process is deoxidized by “silicon followed by aluminium”. The content of oxide inclusions and AlN inclusions in the sample is equal, and the amount of Ca inclusions only accounts for about 12 % of the total inclusions. The corrosion of CaF2 from desulfurizer to refractories results in the amount of Mg inclusions in RH desulfurization sample twice as much as that in non-desulfurization. Related Articles | Metrics Select Influence of electromagnetic field on molten steel flow and heat transfer in slab continuous casting tundish Steelmaking    2019, 35 (2): 39-45.   Abstract （120）            Knowledge map    Save Channel type induction heating tundishis developed by utilizing the thermal effect and force effect of electromagnetic field. Its purpose is to achieve low superheat and constant temperature pouring and thus promoting the removal of non-metallic inclusions in molten steel. In this study, a three-dimensional mathematical model of electromagnetic induction heating tundish for channel slab continuous casting was carried out.The molten steel flow and heat transfer in slab continuous casting tundish with or without electromagnetic field were investigated under current technological conditions. The results show that the molten steel in the channels of the slab continuous casting tundish is subjected to eccentric electromagnetic force pointing to the center of the tundish under the action of electromagnetic field. The distribution of electromagnetic force is larger near the wall and smaller in the center. The eccentric electromagnetic force causes the centripetal rotational flow of molten steel in the channel. Joule heat generated by electromagnetic field mainly distributes in the latter half of the two channels. After 145 seconds of heating, the temperature of molten steel in the channels increases by 31.8 K. Related Articles | Metrics Select Quality control of QP980 slab for ultra-high strength automotive steel Steelmaking    2019, 35 (2): 46-50.   Abstract （118）            Knowledge map    Save In view of the deep oscilation mark, longitudinal crack and transverse brittle fracture of the surface of QP980 continuous casting slab for high strength automobile, by measuring the high temperature plasticity and thermal conductivity of QP980 steel, it is clear that the serious peritectic reaction is the cause of the quality defect. By optimizing the mold flux, secondary cooling and hot charging process, the quality defects of the slab are eliminated and the quality of hot rolled coils is good. Related Articles | Metrics Select Study on influence of factors on castability of ultra-low-carbon P-added high-strength steel Steelmaking    2019, 35 (2): 51-56.   Abstract （171）            Knowledge map    Save Ultra-low-carbon P-added high-strength steel has IF steel characteristics and is characterized by adding a certain amount of alloying elements such as P, Mn and Nb to achieve solid solution strengthening and increasing the strength of the steel without affecting the plasticity of the steel, but the high P content of molten steel is likely to cause nozzle clogging. By investigating the direct key influence factors of the formation and removal of oxide inclusions (Al2O3 mainly) in steel, analyzing the internal mechanism, conducts relevant theoretical research and production test, optimizing the selection by process, controlling the high temperature and high P content of molten steel at converter end-point, optimizing RH refining microalloying process and full process time matching, reducing the formation of inclusions in steel, and promoting the accumulation of inclusions, the castability of molten steel was improved. The average value of T.O mass fraction leaving RH station is 2510-6, and the average value of T.O mass fraction in continuous casting tundish is 1910-6. Finally, the problem of castability of P-added high-strength ultra-low carbon steel has been solved, and large-scale stable production with100t LD→RH→CC process flow and stable 4 furnace sequence continuous casting have been realized. Related Articles | Metrics Select Research and practice of low hot metal consumption technology Steelmaking    2019, 35 (2): 57-62.   Abstract （185）            Knowledge map    Save With scrap adding in multiple steps and BOF compensation heating at 210 t converter in Hunan Valin Lianyuan Iron &Steel Co.,Ltd, the hot metal consumption can be greatly reduced. Meanwhile, with denitrification capacity improved, over-blowing and reblowing reduced, and power system at low temperature in the early stage of IF station optimized, the calcium treatment eliminated, deoxidization process optimized, nitrogen pickup can be effectively reduced. With optimized ladle slag modification, TFe in the slag can be reduced, thus RH treatment time can be prolonged according to Al addition and oxygen blowing, and T.O content in tundish can be stabilized. Ultimately, the comprehensive hot metal consumption of high value added steel can be reduced to 820 kg/t, in addition, high value added steel with LF treatment can have 99.8 % of liquid steel with w(N)≤60×10-6, after RH treatment , liquid steel in tundish with w(T.O)≤28×10-6 can reach up to 95 %. Therefore, the steel output has been greatly increased, resulting in huge economic benefit. Related Articles | Metrics Select Cause analysis and control measures of 20CrMnTiH steel hard spots Steelmaking    2019, 35 (2): 63-65.   Abstract （79）            Knowledge map    Save The hard points in 20CrMnTiH gear steel can cause difficulty in sawing, this kind of difficult sawing quality problem is more intuitive, and saw blade fatigue life is greatly reduced under the same cutting speed. Through the LF refining furnace submerged arc operation, reasonable bottom blowing argon stirring system, use high aluminum preslug system, implementation of such measures as tundish sealing, control the oxygen content and nitrogen mass fraction in 20CrMnTiH gear steel under 14×10-6 and 60×10-6 respectively, the hard-point defects in 20CrMnTiH gear steel can be effectively solved. Related Articles | Metrics Select Study on CO2 adsorption reaction of converter slag Steelmaking    2019, 35 (2): 66-69.   Abstract （115）            Knowledge map    Save The adsorption capacity of converter slag for pure CO2 and CO2 in simulated blast furnace gas was detected by PCA-2200 chemical adsorption analyzer. Regardless of the influence of other gases in the blast furnace gas,the simulated blast furnace gas was consisted of 19.89% (volume fraction) CO2, 25.00 % CO, and 55.11% N2. The results show that the temperature has a notable effect on the CO2 adsorption reaction of converter slag. Increasing temperature improves the adsorption capacity of converter slag for CO2. At 400 ℃,the amount of CO2 adsorbed by converter slag per kilogram of pure CO2 and simulated blast furnace gas is 3.448 g and 5.575 g, respectively. However, when the reaction temperature rises to 500 ℃ and 550 ℃, the adsorption capacity of converter slag for pure CO2 is higher than that for CO2 in simulated blast furnace gas. At 550 ℃, the uptake for pure CO2 and CO2 in simulated blast furnace gas by the per kilogram converter slag reached the highest, which are 9.339 g and 7.062 g, respectively. Related Articles | Metrics Select Kinetic model of carbonation of steel slag Steelmaking    2019, 35 (2): 70-74.   Abstract （96）            Knowledge map    Save Steel slag carbonate reaction can effectively transform free calcium oxide in steel slag into the carbonates and achieve the purpose of volume stabilization. The carbonation process of steel slag and the kinetics were studied with unreacted core model in this paper. The variation of the particle pore mechanism during the reaction process was found outaccording to the literatures, the diffusion coefficient was corrected then the relationship between the diffusion coefficient and the conversion ratio was obtained. According to this model, the controlling process of the reaction of different particle size was judged. It was found that theparticle size of steel slagshould be controlled within 180 μm. Related Articles | Metrics Select Pollution analysis and treatment methods of stainless steel slag Steelmaking    2019, 35 (2): 75-78.   Abstract （89）            Knowledge map    Save Stainless steel slag is a solid waste in stainless steel company with containing a large amount of chromium, and it is harmful because of the leaching risk of chromium in the environment. In this paper, based on the chemical composition, phase composition and existing state in stainless steel slag, the contamination of stainless steel slag was mainly studied. Furthermore, treatment methods of stainless steel slag for harmless at home and abroad were mainly introduced. Related Articles | Metrics Select Discussion on the index of steel cleanliness Steelmaking    Accepted: 01 January 1900 Select The practice of dephosphorization and demanganization in the process of producing industrial iron SYTB in Qiangang Steelmaking    Accepted: 01 January 1900 Select Research and practice of nitrogen control technology for converter smelting ER50-6 welding wire steel Steelmaking    Accepted: 01 January 1900 Select Improving melting position of calcium core wire during wire-feeding process Steelmaking    Accepted: 01 January 1900 Select Numerical simulation of effect of channel tilt angle on induction heating tundish Steelmaking    Accepted: 01 January 1900 Select Calibration of drainage sand parameter and numerical simulation of the service process based on PFC Steelmaking    Accepted: 01 January 1900 Select Research on control of central segregation of 16MnCr5 steel continuous casting slab Steelmaking    Accepted: 01 January 1900 Select Ultrasonic nondestructive testing and characterization for internal defects in the slab Steelmaking    Accepted: 01 January 1900 Select Steelmaking    Accepted: 01 January 1900 Select Development of 17CrNiMo6 heavy forgings of high strength carburized gear steel Steelmaking    Accepted: 01 January 1900 Select Analysis of the reasons for the inconsistent detection of the length of the extra-thick plate Steelmaking    Accepted: 01 January 1900 Select Study on control of B-type inclusion in high grade pipeline steel Steelmaking    Accepted: 01 January 1900 Select Progress and prospects of steelmaking technology in Hesteel Steelmaking    2019, 35 (4): 1-7.   Abstract （118）            Knowledge map    Save The technological progress of steelmaking process in Hesteel was briefly introduced in this paper. And the key economic and technical indicators of Hesteel were comparative analyzed simultaneously. The following techniques were described in detail, and it include precise and clean steel control technology, dry dust removal in converter, automatic steelmaking technology based on flue gas analysis, continuous casting slab heavy pressure technology, steel slag quenching and waste heat recovery,and big data quality control system. All of above techniques have been applied in Hesteel production line which provided favorable support for low costing green steelmaking and high grade, high value-added product development. In addition, the direction of development would be point out in the paper. And the intelligent steelmaking, jet metallurgy for big scrap radio and process flow control technology being developed and applied in the further to show innovative ability of Hesteel were also introduced in the paper. Related Articles | Metrics Select Experimental study on optimization of molten iron pre-desulfurization process by KR Steelmaking    2019, 35 (4): 8-11.   Abstract （104）            Knowledge map    Save Through the experiments of KR desulfurization operation and process parameters, the influencing factors of KR molten iron pre-desulfurization are analyzed and studied. The results show that, amount of blast furnace slag in ladle, insertion depth of stirring paddle, stirring time, stirring speed and quality of stirring paddle have a great influence on desulfurization rate of molten iron. Improvement measures such as the slag is removed before desulfurization, and controlling the insertion depth of the stirring paddle at about 1.0 m, the stirring time is 10–14 min, and the stirring speed is 80 r/min are formulated, and the application effect of improving desulfurization rate is achieved. Related Articles | Metrics page Page 1 of 2 Total 80 records First page Prev page Next page Last page