• Transactions of Materials Processing
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• v.3 no.4
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• pp.440-453
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• 1994

The multi-stage deep-drawing processes including normal-drawing, reverse-drawing, and re-drawing are analyzed by use of the rigid-plastic finite element method. Computational results on the punch/die loads and thickness distributions were compared with the experiments of the current drawing processes. Deep-drawing processes of the redesigned shell to improve the specific strength and stiffness were simulated with the numerical method developed. With varying several process parameters such as blank size, corner radii of tools, and clearances, the simulation results showed the improvements in reducing the forming loads. Also forming defects were found during simulation and appropriate blank size could be verified.

• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.12
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• pp.2936-2948
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• 1993

Multi-stage deep drawing is an important sheet metal forming process. The deformation mechanisms of sheet metals during forming processes are complicated mainly due to the geometry and the lubrication of tools involved, the formability and the anisotropic behaviour of the material. The multi-stage deep-drawing processes including normal-drawing, reverse-drawing, and re-drawing are analyzed by use of the rigid-plastic finite element method. The anisotropic behaviour represented by r-value can be incorporated into the formulation. Punch/die loads and thickness distributions were obtained as results of simulating axisymmetric deep drawing processes. The computed results showed good agreements with experiments.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.04a
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• pp.630-634
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• 1997

In this paper,we will discuss in the forming process design of the making engine pulleys for automobiles. These pulleys are required to be made by precision deep drawing process because these are to be combined with bearings and engine timing belts. These pulleys are used of cold rolled steel plates starting with the initial blanking size of 115.2mm and the initial thickness of 1.2mm. Our deep drawing process is designed the continuous 5-steps process, that is, 1'st deep drawing, 2'nd reverse redrawing, 3'rd trimming, 4'th drawing-ironing and 5'yh piercing. This process need no in-process annealing.

• Journal of Industrial Technology
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• v.19
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• pp.67-74
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• 1999

The mechanical properties including forming limit and deep-drawability of commercially-used sheet metals were experimentally estimated in this study. Uniaxial tensile test to obtain basic mechanical properties was carried out, followed by limiting dome height (LDH) test and forming limit diagram (FLD) test to quantitatively evaluate the sheet-formability. Deep drawing and reverse drawing tests were also performed to find out the critical values of the blank holding force and the gap between the die and the blank holder which enabled the deep drawing and reverse drawing of a successful cop without any wrinkle or fracture. The thickness of the cup wall along the rolling-, transeverse- and $45^{\circ}$-directions was measured and compared with one another. And the punch force-stroke curve and the critical punch force expected from the theory coincided with the experimental result very well for mild steel while not for aluminium alloy.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1996.11a
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• pp.943-948
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• 1996

In this paper. we will discuss in making large size cylindrical shells with multithickness wall sections such as straight, stepped, tapered sides. These shells are constructed of type 6061 O temper aluminum starting with a blanking size of 877 mm plate. Its diameter to length ratio of 1 to 2.78 and a 36.7％ wall reduction is achieved by our continuous deep drawing process. This process required no in-process annealing. But after cold working, these shells is performed heat treatment to T6 condition. These shells are used for the making of seamless LPG pressure vessels after the spinning process. This process is composed of deep drawing, reverse redrawing, drawing-ironing and several ironing processes. In the verification of forming process design, we used DEFORM code.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2000.04a
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• pp.721-723
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• 2000

Deep Drawing공정은 2차원 박판(Sheet Metal)에 그림이나 글자를 인쇄한 다음, 박판을 다이에 고정하고 펀치로 눌러서 3차원의 제품을 생산하는 소성가공의 한 방법이다. 그러므로, 2차원 평면인 박판에 어떻게 적절히 인쇄하여, 가공 후의 3차원 제품에 원하는 그림과 글자가 나타나게 할 수 있는지가 문제가 되고 있다. 본 논문에서는 Deep Drawing공정을 거쳐 완성된 제품을 측정한 후, 형상 역공학(Reverse Engineering) 기술을 이용하여 측정 데이터(Measured Points Data)를 입력으로 하는 매개변수 곡면 (Parametric Surface)을 만들고, Deep Drawing공정 전의 박판에 대한 매개변수 곡면을 만든 다음 두 곡면간의 매핑을 통해 위의 문제점을 해결하고자 한다.

• Korean Journal of Construction Engineering and Management
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• v.15 no.3
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• pp.3-11
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• 2014

Recently, remodeling construction project has been prevalently conducted in major city areas in Korea. However, remodeling construction project has a difficulty in conducting a construction because of non-existing drawing or lack of drawing information. To solve these problems, modeling techniques by using reverse engineering have been widely studied in other industries such as aerospace and automobile industry. But reverse engineering techniques have not been used in remodeling construction projects because those technology haven't supplied less accuracy during required time for surveying. So, this study suggests optimal method of acquiring accurate 3D laser scanner information for reverse engineering at interior remodeling project.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.20 no.12
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• pp.3728-3740
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• 1996

High-quality cups of deep drawing ratio of more than four cannot be simply drawn by conventional drawing and redrawing processes. In the present study, after the first deep drawing process, subsequent hydromechanical reverse redrawing with controlled radial pressure is employed. In order to increase the deep drawing ratio up to muchmore than four, the radial pressure should be controlled independently of the chamber pressure and thus an optimum forming condition can be found easily by varying the radial pressure. The process has been subjected to finite element analysis by using the rigid-platic material modeling considering all the frictional conditions induced by the hydrostatic pressure. In order to consider the pressure effect on the sheet, the pressure distributions on the flange part and the side wall part are calculated mumerically from simplified Navier-stokes equation. The comparison of the computation with the experiment has shown that the finite element modeling can be conveniently emplyed for the design of the process with reliability from the viewpoint of formability.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2007.11a
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• pp.183-184
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• 2007

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2003.10a
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• pp.412-419
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• 2003

The most product is manufactured by mould in usual life. From drawing to manufacturing is to be automatically. But inspection is handwork usually. An alternative idea of this problem is reverse engineering. In this study, press forming is measured by 3D non-contact coordinate measuring machine and problem will be analyzed by comparing with 3D data Through the study, it will achieve improvement of press mould process.