Control Technology of Internal Quality for CC Billet

2011 ◽  
Vol 415-417 ◽  
pp. 1729-1734 ◽  
Author(s):  
Hong Pan
Keyword(s):  
Quality Control ◽  
Casting Process ◽  
Electromagnetic Stirring ◽  
Internal Quality ◽  
Control Technology ◽  
Secondary Cooling ◽  
Continuous Casting Process ◽  
Segregation Index ◽  
Round Billet

The effect of process parameters of secondary cooling and electromagnetic stirring (EMS) on internal quality for CC billet is investigated. With these studies, the continuous casting process is optimized, and the internal quality of square/round billet is improved as well. Comprehensive technologies for internal quality control of square/round billet in Panzhihua Steel have been proposed. The results of industrial tests show that the comprehensive rate below level 1.0 of internal defects of center porosity, center segregation and center cracks is more than 97%, and carbon segregation index is in the range of 0.93~1.09. The quality of square/round billet can meet the requirement of consumers absolutely.

Study on Quality Control Technology for Square/Round Billet in Panzhihua Steel

2011 ◽  
Vol 396-398 ◽  
pp. 1138-1144 ◽  
Author(s):  
Hong Pan ◽  
Guo Rong Wu ◽  
Zhi Qiang Li
Keyword(s):  
Quality Control ◽  
Continuous Casting ◽  
Continuous Caster ◽  
Casting Process ◽  
Secondary Cooling ◽  
Mold Powder ◽  
Segregation Index ◽  
Round Billet ◽  
Billet Quality

The continuous casting technologies of the new square/round billet continuous caster in Panzhihua Steel have been studied. And on this basis, the effect of process parameters of primary cooling, mold powder, secondary cooling and electromagnetic stirring (EMS) on billet quality is investigated. With these studies, the continuous casting process is optimized, and the quality of square/round billet is improved as well. Comprehensive technologies for quality control of square/round billet in Panzhihua Steel have been proposed. The results of industrial tests show that the accept rate of surface quality for square billet is 98.44%, and that is 97.42% for round billet; the comprehensive rate below level 1.0 of internal defects of center porosity, center segregation and center cracks is more than 97%, and carbon segregation index is in the range of 0.93~1.09. The quality of square/round billet can meet the requirement of consumers absolutely.

Research of Transverse Corner Crack and Optimization of Concasting Process for Bloom of Peritectic Steel Q235D

2011 ◽  
Vol 284-286 ◽  
pp. 1115-1119
Author(s):  
Cheng Gong Yao ◽  
Shou Qian Yuan ◽  
Lie Chen ◽  
Zhi Jun Wang ◽  
Hai Long Wang ◽  
...  
Keyword(s):  
Crack Formation ◽  
Cooling Water ◽  
Casting Process ◽  
Electromagnetic Stirring ◽  
Continuous Casting Process ◽  
Steel Composition ◽  
Corner Crack ◽  
Peritectic Steel ◽  
Casting Production

Q235D is one kind of peritectic steel, so the casting production inevitably encounter the universality defects of peritectic steel casting. The bloom(250mm×280mm) of Q235D is produced by 60t consteel EBT—LF(VD)—CC process at Xining Special Steel. The main problem in the production is the transverse corner crack, finally lead to occur the cracks and “triangular gaps” at surface of round bar（Φ130mm）after rolled. In order to eliminate the defects caused by transverse corner crack of bloom, the morphology and microstructure and principle of crack formation is researched. The results showed that the crack is caused by stress along the intergranular, and no obvious segregation and particles founded around the defects. The following parameters on the continuous casting process are optimized: steel composition, superheat, the choice of a various slag, the cooling water of different section, casting speed and the electromagnetic stirring parameters. Finally the cracking defects of the bloom is eliminated, and the quality of the bar is optimized.

Study on Internal Quality of Billets for 20CrMnTiH Steel

2014 ◽  
Vol 941-944 ◽  
pp. 132-137
Author(s):  
Hong Guang Li ◽  
Tian Ming Chen ◽  
Liang Chen ◽  
Jia Qi Wang ◽  
Wen Zhong Yang
Keyword(s):  
Quality Control ◽  
Quality Improvement ◽  
Casting Speed ◽  
Cooling System ◽  
Current Intensity ◽  
Internal Quality Control ◽  
Internal Quality ◽  
Secondary Cooling ◽  
Carbon Segregation

According to the requirement of 20CrMnTiH steel, the effects of casting peed, EMS current intensity and secondary cooling system on internal quality of billets are studied. The results show that, it is beneficial to internal quality control of 20CrMnTiH billets when the casting speed is in the range of 1.2~1.4m/min, and when the current intensity of EMS is 380A, the level of center porosity can be controlled in 1.0, the index of carbon segregation can be controlled in 1.08 and equiax crystal ratio reaches 34.9%. Furthermore, it is beneficial to internal quality improvement when weak secondary cooling system is adopted. With the application of the studies, the quality of billet macrostructure and hardenability can meet the requirement of 20CrMnTiH steel.

Optimization and Application of Secondary Cooling on 37Mn5 Steel ø210mm Round Billet

2013 ◽  
Vol 706-708 ◽  
pp. 163-166
Author(s):  
Wei Chen ◽  
Bao Xiang Wang ◽  
Yong Ping Feng ◽  
Na Zheng ◽  
Ying Chen
Keyword(s):  
Heat Transfer ◽  
Mathematical Model ◽  
Computing Time ◽  
Shrinkage Cavity ◽  
Internal Quality ◽  
Two Dimensional ◽  
Shell Formation ◽  
Secondary Cooling ◽  
Round Billet

Aiming at enhancing the internal quality of 37Mn5 steel, a two-dimensional heat transfer mathematical model is established based on Finite Element Method. The synchronization between computing time and casting time is implemented by use of slice moving method. The reasonable of the model is verified by tested temperature. The process of solidification and shell formation is simulated for 37Mn5 steel ∅210mm round billet. The studied results indicate that: after optimization, the internal quality of billet is improved significantly; the defects such as center porosity, shrinkage cavity, intermedium cracks and center cracks were decreased obviously; defects above grade 1 were basically avoided.

Development of Electromagnetic Swirling Flow in Immersion Nozzle in Continuous Casting Process of Steel

2011 ◽  
Vol 295-297 ◽  
pp. 1284-1288 ◽  
Author(s):  
De Wei Li ◽  
Zhi Jian Su ◽  
Li Wei Sun ◽  
Katsukiyo Marukawa ◽  
Ji Cheng He
Keyword(s):  
Continuous Casting ◽  
Swirling Flow ◽  
Casting Process ◽  
Continuous Casting Process ◽  
New Process ◽  
Electromagnetic Generator ◽  
Set Up ◽  
The Magnetic Field ◽  
Immersion Nozzle

Swirling flow in an immersion nozzle is effective on improving quality of casting block and casting speed in continuous casting process of steel. However, a refractory swirl blade installed in the nozzle is liable to cause clogging, which limit the application of the process. In this study a new process is proposed, that is a rotating electromagnetic field is set up around an immersion nozzle to induce a swirling flow in it by Lorentz force. New types of swirling flow electromagnetic generator are proposed and the effects of the structure of the generator, the coil current intensity and frequency on the magnetic field and on the flow field in the immersion nozzle are numerically analyzed.

scholarly journals Study of the Effect of Carbon on the Contraction of Hypo-Peritectic Steels during Initial Solidification by Surface Roughness

Metals ◽  
2018 ◽  
Vol 8 (12) ◽  
pp. 982 ◽  
Author(s):  
Dazhi Pu ◽  
Guanghua Wen ◽  
Dachao Fu ◽  
Ping Tang ◽  
Junli Guo
Keyword(s):  
Surface Roughness ◽  
Cooling Rate ◽  
Solidification Process ◽  
Casting Process ◽  
Continuous Casting Process ◽  
Peritectic Steel ◽  
Laser Confocal Microscope ◽  
Initial Solidification

In the continuous casting process, the shrinkage of the peritectic phase transition during the initial solidification process has an important influence on the surface quality of peritectic steel. The initial solidification process of 0.10C%, 0.14C%, and 0.16C% peritectic steels was observed in situ by a high temperature laser confocal microscope, and the contraction degree during initial solidification was characterized by surface roughness. The results showed that under the cooling rate of 20 °C/s, the surface roughness value Ra(δ/γ) of 0.10C% peritectic steel was 32 μm, the Ra(δ/γ) value of 0.14C% peritectic steel was 25 μm, and the Ra(δ/γ) value of 0.16C% peritectic steel was 17 μm. With increasing carbon content, the contraction degree of the δ→γ transformation decreased, and the value of the surface roughness Ra(δ/γ) declined. Therefore, surface roughness can characterize the contraction degree of the δ→γ transformation in the initial solidification process of peritectic steel under the condition of a large cooling rate.

Quality control as a fundamental institute of medical activities (review of literary sources)

2021 ◽  
pp. 39-48
Author(s):  
Larisa Arkadyevna Karaseva ◽  
Tatyana Vladimirovna Bessonova
Keyword(s):  
Quality Of Life ◽  
Quality Control ◽  
Medical Care ◽  
Internal Quality Control ◽  
Internal Quality ◽  
Quality And Safety ◽  
Professional Activities ◽  
Literary Sources ◽  
High Level

The aim of the study, analyze and evaluate the quality control and safety of medical activities carried out in medical organizations. Results: the essence of the concept of quality control in the field of medical care was determined, criteria for assessing the quality of medical activities were identified, the main aspects of developing a program for internal quality control and safety of medical activities were characterized, key risks existing in medical activities were identified, directions for improving the quality and safety of professional activities of medical workers. Conclusion: modern approaches to the organization of quality control and safety of medical activities make it possible to ensure a high level of medical care provided to the population and improve the quality of life of the population as a whole.

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