• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.11
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• pp.1437-1443
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• 2011

Thick plates produced by the rolling process are used as the basic elements of ship structures. In this paper, we present a setup model for controlling the asymmetric factors causing plate bending in the width direction during plate rolling. A series of three-dimensional finite element analyses is conducted to predict the relationship between various asymmetric factors and plate bending. The setup model is developed by performing regression on the relationship to produce linear equations with several nondimensional parameters. The setup model is verified with a pilot rolling test in which variations in thickness and temperature differences in the width direction exist. The results show that the bending curvatures predicted by the model are in fairly good agreement with the measured results for those asymmetric factors.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.37 no.9
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• pp.1117-1125
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• 2013

A finite element based approach that can be used to investigate the plane-view shape and crop loss of a material during plate rolling is presented. We employed a three-dimensional finite element model to continuously simulate the shape change of the head and tail of a plate as the number of rolling passes increases. The main feature of the proposed model lies in the fact that the multistage rolling can be simulated without a break because the rolling direction of the material is reversibly controlled as the roll gap sequentially decreases. The material constants required in the finite element analysis were experimentally obtained by hot tensile tests. We also performed a pilot hot plate rolling test to verify the usefulness of the proposed finite element model. Results reveal that the computed plane-view shapes as well as crop losses by the proposed finite element model were in good agreement with the measured ones. The crop losses predicted by the proposed model were within 5% of those measured from the pilot hot plate rolling test.

• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.7
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• pp.1278-1284
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• 1992

In plate rolling, it is desired to reduce the trimming loss by controlling the formation of defective end shapes. For this reason, edge rolling is frequently performed in the plate mill. In this paper, the effect of various process variables on the deformation of plate ends in edge rolling is examined by conducting experiments and finite element computer simulation. A focus is given to investigating the effect of edging on the width of the deformed plate trimming-free plate rolling.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.10 no.2
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• pp.124-129
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• 2011

The thick plate produced by rolling process is used as the basic members of a ship structure. In this paper, we present a setup model to control the asymmetric factors causing plate bending in the upper or lower direction during rolling. A series of finite element analysis are conducted to predict the relationship between various asymmetric factors and plate bending. The setup model is developed by regressing the relationship to the linear equations with several non-dimensional parameters. The setup model is verified by a pilot rolling test and applied to actual rolling conditions. Results show that the model is substantial to predict the asymmetric deformation in the plate rolling process.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2006.05a
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• pp.137-142
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• 2006

제철소 후판공장에서는 두꺼운 슬라브(Slab)를 압연하여 사각형태의 철판인 날판(Mother Plate)을 생산하고, 이를 주문(Plate) 사이즈에 맞게 다시 절단을 하게 된다. 이때 동일 슬라브라 하더라도 압연방법에 따라 다양한 사이즈의 날판을 생산할 수 있다. 여기에서 다루고 있는 후판 날판설계 문제는 주어진 주문을 대상으로 최소 개수의 슬라브를 사용하여 생산하는 문제를 말한다. 이를 위해 최적의 날판 사이즈를 결정하고, 각 날판에 주문들을 배치하게 된다. 본 논문에서는 후판 날판설계문제를 two-stage guillotine cutting problem의 변이로 모델을 세우고, 이를 위한 효율적인 휴리스틱을 제시하였다. 그리고 실 데이터를 대상으로 컴퓨터 실험을 통해 휴리스틱을 효율성을 검정하였다.

• Journal of the Korean Society for Precision Engineering
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• v.12 no.3
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• pp.73-81
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• 1995

To find a way for establishing work roll initial crown according to roll conditions, computer simutation for predicting plate crown in plate mill is done and effects of roll conditions on plate crown is analyzed. Toll gap rorfile and plate crown are measured to be compared to the calculated values. As a result, regression equation to establish work roll initial crown according to roll conditions such as backup roll diameter, backup roll crown and work roll diameter is obtained.

• Journal of Korean Society of Steel Construction
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• v.15 no.3
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• pp.331-339
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• 2003

The study discussed in this paper investigated the material characteristics for the Thermo-Mechanical Control Process(TMCP) plates, which are controlled by several factors such as rolling, cold-stripping, cooling rate, and fixed carbon quantity. The suitability of thick TMCP steel plates as structural steel was also estimated through several experiments and with the us of a statistical method to analyze mill certificate sheets provided by the manufacturer. The results of this study are as follows: the TMCP steel plates showed stable values of the composition parameter ($P_cm$) and the carbon equivalents ($C_eq$ ) with satisfied yield strength, ultimate strength, and low-yield ratio.

• Transactions of the Korean Society of Mechanical Engineers
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• v.15 no.1
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• pp.376-385
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• 1991

For manufacturing trimming-free plates which have rectangular shaped edges and straight edges in as-rolled state, it is necessary to investigate rolling characteristics of overlap, bulge and width deviation etc. in a standardized plate rolling process. The present wok is for preventing edge overlap as the first approach to develop trimming-free plate rolling technique. An experimental study on overlap control was done with plasticine material in order to examine influence factors and find a control method by use of a laboratory mill scaled down to one tenth of actual production mill. It was found that edge overlapping was increased with the increase of slab thickness and of broadside rolling ratio, but decreased with the increase of chamfered amount on slab edges. In the simulated rolling experiment with edge chamfered slabs of various chamfered angles, the chamfered angle of 60.deg. was the most effective one for reducing overlapping irrespective of slab thickness and of broadside rolling ratio.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1993.10a
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• pp.499-504
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• 1993

To find a way for establishing work roll initial crown according to roll conditions, computer simulation for predicting plate crown in plate mill is done and effects of roll conditions on plate crown is analysed. Roll gap profile and plate crown are measured to be compared to the calculated values. As a result,a regression equation to establish work roll initial crown according to roll cooditions such as backup roll diameter, backup roll crown and work roll crown is obtained.

• Transactions of Materials Processing
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• v.8 no.2
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• pp.208-215
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• 1999

To increase rolling yields by minimizing trimming losses of hot-rolled plate, optimization logic for the edger model has been developed. The logic to determine optimum edging amount model has been formulated on the basis of actual production rolling data. In case of broadside rolling, the fish tail shape at the sides of plate was better for reducing the crop loss and this could be achieved when the edging amount of broadside rolling was increased. At a given broadside rolling ratio, methodology to determine optimum edging amount for the finish rolling which could minimize the width deviation of plate were systematically derived. Therefore, for a given broadside rolling condition and the permissible tolerance in width deviation of plate, it was possible to optimize the edging amount in finish rolling to maximize rolling yields. The application of optimization logic in this study increased rolling yields from approximately 10% to 30% at various longitudinal eding raitos.