• Title/Summary/Keyword: sizing mill

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Finite Element Analysis of Slab Deformation under the Width Reduction in Hot Strip Mill (열간압연 폭압하시 슬래브 변형거동의 유한요소해석)

  • 천명식;정제숙;안익태;문영훈
    • Transactions of Materials Processing
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    • v.12 no.7
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    • pp.668-674
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    • 2003
  • Rigid-plastic finite element analyses on the deformation of slabs at various width reductions have been performed. By using commercial finite element code, dog-bone profile, crop profile and the longitudinal width profile after edging and Horizontal rolling have been analysed. The deformation behavior of slab for the heavy edger mill has also been compared with that for the sizing press. From the deformation analyses, it was found that the sizing press-horizontal rolling method is more efficient in width reduction than that of heavy edger mill-horizontal rolling. The results of finite element analyses fer the deformation of slab were well confirmed by the actual operational data. It was found that the amount of width variation after sizing and rolling is about 5∼10mm.

Plastic characteristic analysis of width reduction process in hot roughing mill (열간조압연 공정에서의 폭 압하 공정시 슬래브의 변형 특성)

  • Heo, Su-Jin;Lee, Sang-Ho;Byun, Sang-Min;Park, Hae-Do;Lee, Jong-Bin;Kim, Byung-Min
    • Proceedings of the KSME Conference
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    • 2007.05a
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    • pp.544-548
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    • 2007
  • In general, final width of hot strip should be accomplished in this stage because width reduction of strip hardly appears during typical finishing mill. However, it is difficult to control the width of strip in the roughing mill process as the horizontal rolling of strip is subsequently performed after the vertical rolling. It is therefore important to obtain the deformation rolling direction on strip width to minimize the width spread of strip during horizontal rolling after vertical rolling. Generally there is Sizing press type and Edger-roll type. The width reduction process in sizing press has small amount of width spread compared with the edger. However, productivity by the sizing press process is much lower than those of the edger. In this study, sizing press and Edger-roll process parameters in a sheet rolling mill were set at specified values and the effect of the change in these parameters on product quality and process performance were evaluated.

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Design of the Anvil Shape in Sizing Press for Decrease of the Defect Generated Width Reduction (사이징 프레스에서 폭 압하 공정중 결함 저감을 위한 엔빌의 형상설계)

  • Lee, S.H.;Lee, S.J.;Lee, J.B.;Kim, B.M.
    • Transactions of Materials Processing
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    • v.18 no.1
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    • pp.52-58
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    • 2009
  • Generally, a vertical rolling process is used to achieve extensive width reduction in hot strip mill. However, it is impossible to avoid the defects such as dog-bone and edge-seam defect. The sizing press process has been developed in response to the defects mentioned above. Especially, this study is carried out to investigate the deformation of slab by two-step sizing press. The deformation behavior of slab in the sizing press process is more favorable than that in conventional vertical rolling edger. The FE-simulation is applied to predict the deformation behavior of the slab. In this paper, the several causes of the asymmetrical deformation are mentioned for the purpose of understanding of the anvil shape. Load, dog-bone and edge-seam defect are discussed in width sizing process considering the anvil shape. And to reduce the problems generated at rougher mill just after sizing press, these are studied in this paper. The deformation behavior of slabs and optimum anvil shape are obtained by rigid-plastic finite element analyses and neural network.

Minimization of Crop Length by Sizing Press in Hot Rolling Mill (열간 조압연 공정에서 2단 사이징 프레스에 의한 크롭 최소화)

  • Heo, S.J.;Lee, S.H.;Lee, S.J.;Lee, J.B.;Kim, B.M.
    • Transactions of Materials Processing
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    • v.17 no.8
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    • pp.619-626
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    • 2008
  • In this study, design methodology to determine optimal shape of the anvil in sizing press process has been proposed to minimize crop length of the AISI 1010 slab in horizontal rolling after width reduction. Shape of anvil were selected to 12 cases by design of experiment, and the dog-bone shapes and the crop length were determined by FE-analysis. Also, the anvil shape, which has minimum crop length, were determined by artificial neural network(ANN). As a result of FE-analysis, it can be seen that the crop length was increased with increasing center thickness in the dog-bone shape after width reduction. The anvil shape which has minimum crop length, was estimated to ${\theta}_{1}=21^{\circ}{\theta}_{2}=14^{\circ}$ by FE-analysis and ANN.

Effect of White Water Quality on AKD Sizing of Linerboard (백수의 수질에 따른 라이너지의 AKD 사이징)

  • Lee, Hak-Lae;Seo, Man-Seok;Shin, Jong-Ho;Youn, Hye-Jung
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.38 no.2 s.115
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    • pp.9-15
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    • 2006
  • Neutral sizing is required for linerboard to solve the troubles in strength and process caused by recycled raw materials. AKD sizing efficiency can be influenced by process condition like white water quality, fines retention and so on. Therefore, this study was aimed to evaluate sizing performance of general and fast cure type AKDs using process water obtained from linerboard mill. To evaluate effect of process water quality on AKD sizing, white water was diluted with tap water at the different dilution ratios and UKP slurry was sized using the prepared water. Also, effects of inorganic and organic ion material on sizing were examined. When white water was used for stock forming, UKP sheet showed very low sizing degree. Sizing degree of sheet was increased with increase of dilution ratio because water quality was improved. Especially anionic organic material had a greater influence on AKD sizing than inorganic material. When white water quality was deteriorated, fast cure type AKD showed superior sizing performance to general type AKD.

Sizing Efficiency of AKD in Causticizing Calcium Carbonate Filled Paper

  • Wang, Jian;Liu, Ling;Xu, Yong-Jian
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.46 no.2
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    • pp.1-7
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    • 2014
  • Causticizing calcium carbonate (CCC) is produced as a by-product in the causticization step of the kraft pulping process. It is often calcined in a rotary lime kiln after being dewatered and reused in the causticizing process. But for the China mill, the conventional recycled way is difficult because the CCC is mainly obtained from non-wood pulping materials, which higher silicon content led to serious silicon obstacle. So it is often discarded as solid waste or used in landfill after dewatering and secondary pollution is brought. In order to prevent its secondary pollution, recent years, the CCC is used as a filler in China papermaking industry. In mill trials, the CCC can be used to replace an amount of precipitated calcium carbonate (PCC). Unfortunately, the application scope and dosage of CCC have been limited due to its lower sizing efficiency than PCC. In this study, the reason for the lower sizing efficiency of alkyl ketene dimer (AKD) when CCC was used as a filler was investigated. The results showed that the materials in green liquid, such as insoluble matter in green liquid, silicon and metal ions, were a little influence on the sizing efficiency of AKD. The higher BET and BJH pore volume of the CCC were the main reason for lower sizing efficiency of AKD when it was used as filler.

Effects of Inorganic Coagulants on Sizing and Contamination in Newsprint Mill (무기 응결제가 신문용지의 사이즈도와 공정오염에 미치는 영향)

  • Lee, Tai Ju;Seo, Jin Ho;Lee, Kwang Seob;Jeong, Sung Hyun;Ryu, Jeong Yong
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.47 no.3
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    • pp.40-46
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    • 2015
  • For some Korean newsprint mill, addition level of aluminum sulfate has been reduced because sulfur from aluminum sulfate has detrimental effect on the efficiency of anaerobic water treatment. At this moment, an unexpected decrease in sizing degree of TMP mixed newspaper was occurred. The phenomena means that hydrophobic substance usually originated from TMP cannot be fixed on the paper. This study focused on effect of alum and PAC on sizing of paper and contamination. Also, substitutability of PAC was discussed as a possible alternatives of aluminum sulfate under anaerobic condition of water treatment. Evaluation of sizing degree and pitch deposit potential were performed at the varied addition level of PAC and aluminum sulfate. Hydrophobic substance mainly derived from TMP could be fixed on the surface of fiber by PAC. Fines retention was not changed by replacing aluminum sulfate with PAC. Additionally, fixing of hydrophobic substance without excessive agglomeration can be enhanced by PAC with low molecular weight. Consequently, sizing degree of newspaper and contamination of recycling process of ONP can be controlled by low molecular weighted PAC.

Deformation Behavior of Slab by Two-Step Sizing Press in a Hot Strip Mill (열간 압연에서 2단 사이징 프레스 금형에 의한 슬래브의 변형거동 예측)

  • Lee S. H.;Kim D. H.;Byon S. M.;Park H. D.;Kim B. M.
    • Transactions of Materials Processing
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    • v.14 no.9 s.81
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    • pp.791-797
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    • 2005
  • Extensive width reduction of slabs is an important technology for achieving continuous production between the steelmaking and hot rolling processes. However, the vertical horizontal rolling process has many disadvantages, e.g., large width deviations and less efficient width reduction. This study was carried out to investigate the deformation of slab by sizing press with two steps die. To do it, dog-bone and camber are discussed in width sizing process considering the deformation behavior according to the deviation of anvil velocity and the deviation of initial slab temperature. In this paper, the various causes of the sizing press phenomena are mentioned for the purpose of understanding of rolling conditions. As a result, the optimal anvil shape having a minimum-forming load is obtained by FE-simulation and ANN.