Reducing Surface Cracks and Improving Cleanliness of H-Beam Blanks in Continuous Casting — Improving continuous casting of H-beam blanks

AbstractA beam blank is ideal for H-beam production, but there are more defects in/on beam blanks than other common blanks. The study of the H-beam blank quality assurance system has great significance for production to determine the key factors causing defects and optimise the casting process parameters. Experimental analysis and numerical simulation, based on an actual production process, were used as research methods. The former was used to test and analyse the cracks, inclusions, and the flux in the mould to determine the preliminary factors causing defects in a beam blank. The latter was used to simulate the flow and temperature fields and the movement of inclusions to determine the key factor leading to defects and to optimize the casting process parameters. Online implementation of the recommendations of this project was developed, which proved that it is very useful and efficient to control surface cracks on the web and enhance cleanliness of an H-beam blank.

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Mold taper optimization for continuous casting of H-beam blanks

Metallurgical Research & Technology ◽

10.1051/metal/2019033 ◽

2019 ◽

Vol 116 (5) ◽

pp. 505

Author(s):

Wei Chen ◽

Gaiyan Yang ◽

Liguang Zhu ◽

Gaoxiang Guo ◽

Jiaqi Wang ◽

...

Keyword(s):

Continuous Casting ◽

Casting Process ◽

Air Gap ◽

Surface Cracks ◽

Load Step ◽

Narrow Face ◽

Continuous Casting Process ◽

Step Method ◽

H Beam ◽

Multiple Load

The objective of this study is to optimize the mold taper for continuous casting of H-beam blanks. A thermo-mechanical coupled mathematical model was established to analyze the heat transfer, solidification, and shrinkage of the strand in the mold based on the multiple load step method. Based on the simulation results of the air gap distribution in the mold, the mold taper was optimized at selected points on the surface of H-beam blank mold by minimizing the air gap thickness and the best taper scheme was proposed. The results show that the original mold tapers are relatively larger and the optimum mold tapers are as follows: (1) taper at the flange surface: 0.81%/m; (2) taper at the narrow face: 0.68%/m; (3) taper at the fillet: −1.44%/m. The optimum mold size obtained from taper optimization was used in the actual continuous casting process and based on the results, it can be concluded that the optimum mold taper scheme proposed in this study reduced the formation of surface cracks in H-beam blanks.

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The Effect of Temperature Fluctuation on the Formation of Billet Surface Defect in the Initial Solidification Area

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.148-149.163 ◽

2010 ◽

Vol 148-149 ◽

pp. 163-167

Author(s):

Xiao Li Jin ◽

Zuo Sheng Lei ◽

Kang Deng ◽

Zhong Ming Ren

Keyword(s):

Continuous Casting ◽

Temperature Fluctuation ◽

Surface Defects ◽

Casting Process ◽

Effect Of Temperature ◽

Billet Surface ◽

Maximum Value ◽

Key Factor ◽

Oscillation Marks ◽

Initial Solidification

The heat transfer in steel continuous casting process under mold oscillation was calculated, and temperature fluctuation phenomena was found in the initial solidification area, the maximum value was approximate 16 °C. The effect of different continuous casting parameters on temperature fluctuation were analyzed, and the temperature fluctuation was considered to be a key factor to the formation of oscillation marks. The Index of Temperature Fluctuation(ITF) was proposed to predict the effect of temperature fluctuation on the formation of billet surface defects.

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Acquiring High-Quality Oil Casing Steel 26CrMoVTiB under Optimal Continuous Casting Process Conditions

Metals ◽

10.3390/met9090993 ◽

2019 ◽

Vol 9 (9) ◽

pp. 993

Author(s):

Yingying Zhai ◽

Kefeng Pan ◽

Dapeng Wu

Keyword(s):

Continuous Casting ◽

Water Flow ◽

Process Parameters ◽

Casting Speed ◽

Casting Process ◽

Solidification Structure ◽

Process Conditions ◽

Equiaxed Crystal ◽

Continuous Casting Process ◽

Simulation Results

While the solidification macrostructure of continuous cast billets is an important factor influencing the final performance and rolling yield of oil casing steel, the continuous casting process parameters have a direct influence on the solidification structure. This study simulated the solidification process of the continuous casting round billets of oil casing steel using a cellular automaton–finite element (CAFE) model. According to the simulation results, at a superheat degree of 20–35 K, a casting speed of 1.9–2.1 m/min, and a secondary cooling specific water flow of 0.34–0.45 L/Kg, the solidification structure had a relatively high equiaxed crystal ratio and small average grain radius. Guided by the simulation results, this paper establishes optimal process schemes for producing 26CrMoVTiB steel round billets, comparatively analyzes the equiaxed crystal ratio and central shrinkage of round billets produced according to these schemes, and defines the optimal continuous casting process conditions, which are: superheat degree = 25 K, casting speed = 2.1 m/min, and specific water flow = 0.35 L/Kg. When adopting these process parameters, the 26CrMoVTiB steel round billets demonstrate a tiny central shrinkage and an equiaxed crystal ratio of 45.2%.

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Optimisation of continuous casting process parameters based on coupled heat and stress model

Ironmaking & Steelmaking ◽

10.1179/174328108x378206 ◽

2010 ◽

Vol 37 (2) ◽

pp. 147-154 ◽

Cited By ~ 4

Author(s):

W. Chen ◽

Y.-Z. Zhang ◽

B.-X. Wang

Keyword(s):

Continuous Casting ◽

Process Parameters ◽

Casting Process ◽

Stress Model ◽

Continuous Casting Process

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Numerical Simulation on Optimization of Center Segregation for 50CrMo Structural Alloy Steel

High Temperature Materials and Processes ◽

10.1515/htmp-2015-0026 ◽

2016 ◽

Vol 35 (6) ◽

pp. 583-589 ◽

Cited By ~ 2

Author(s):

Xiangzhou Gao ◽

Shufeng Yang ◽

Jingshe Li ◽

Hang Liao

Keyword(s):

Continuous Casting ◽

Alloy Steel ◽

Process Parameters ◽

Casting Process ◽

Heat Transfer Process ◽

Equiaxed Crystal ◽

Secondary Cooling ◽

Structural Alloy ◽

Continuous Casting Process ◽

Cooling Intensity

AbstractTo improve the center segregation of billet for 50CrMo structural alloy steel, a 3D numerical model of solidification and heat transfer process for continuous casting had been established. The influence law of continuous casting process parameters on the secondary dendrite arm spacing (SDAS) and equiaxed crystal ratio had been obtained. It was shown that reducing superheat and casting speed and increasing the secondary cooling intensity could decrease SDAS. Reducing any one of the three parameters could increase the equiaxed crystal ratio. Adjusting only secondary cooling intensity could not make the SDAS and equiaxed crystal ratio change in the desired direction, but regulating the other two parameters could supply this gap. After optimizing the continuous casting process parameters of 50CrMo billet, the defect of center segregation was solved basically.

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Research and Application of a Rolling Gap Prediction Model in Continuous Casting

Metals ◽

10.3390/met9030380 ◽

2019 ◽

Vol 9 (3) ◽

pp. 380 ◽

Cited By ~ 1

Author(s):

Zhufeng Lei ◽

Wenbin Su

Keyword(s):

Continuous Casting ◽

Process Parameters ◽

Principal Component ◽

Casting Process ◽

Support Vector ◽

New Approach ◽

Value Prediction ◽

Svm Model ◽

Roll Gap

Control of the roll gap of the caster segment is one of the key parameters for ensuring the quality of a slab in continuous casting. In order to improve the precision and timeliness of the roll gap value control, we proposed a rolling gap value prediction (RGVP) method based on the continuous casting process parameters. The process parameters collected from the continuous casting production site were first dimension-reduced using principal component analysis (PCA); 15 process parameters were chosen for reduction. Second, a support vector machine (SVM) model using particle swarm optimization (PSO) was proposed to optimize the parameters and perform roll gap prediction. The experimental results and practical application of the models has indicated that the method proposed in this paper provides a new approach for the prediction of roll gap value.

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