• 한국철도학회:학술대회논문집
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• 한국철도학회 2009년도 춘계학술대회 논문집
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• pp.1618-1623
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• 2009

In this paper, we describe the design method of carbody structure with side-buffer. Recently railroad industry has a new interest with stability, fixed time, low environment pollution and mass transportation. Accidents have little on the railroad but railroad industry is trying to minimize carbody damage and passenger injury in case of accidents. So a side-buffer having anti-climber is applied to meet each special needs. Carbody with side-buffer is assembled with aluminum(6005A-T6) parts that are extruded. As the results of the study, it is showed that carbody with side-buffer has sufficient energy absorbtion about crashworthiness.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 춘계학술대회 논문집
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• pp.748-753
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• 2004

Aluminum alloy is very useful material for high speed transportations due to its high strength and light weight characteristics. Especially because of a weight reduction a large extrustion of aluminum alloy carbody has been manufactured. This aluminum extruded panel is a hallow extruded panel. This shape and thickness is various by designer's sense and experience and VAW's profiles. So it is important to find an optimized shape and thickness of AEP. In this study we get the AEP's thickness to minimize a weight by applying an applying an optimization algorithm. The results of the study can be used as basic guidelines double-deck trains in the future.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 춘계학술대회 논문집
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• pp.980-985
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• 2008

Since its invention at TWI in 1991, Friction Stir Welding (FSW) has become a major joining process in the aerospace, railway and ship building industries especially in the fabrication of aluminium alloys. In an attempt to optimize the friction stir welding process of Al alloys for extrusion Aluminium carbody of HEMU-400X (Extrusion Aluminum 6xxx series), effects of joining parameters such as tool rotating speed, plunging depth and dwelling time on the weld joints properties were evaluated. Experimental tests were carried out for butt joined Al plates. A wide range of joining conditions could be applied to join Al alloys for Extrusion Aluminum 6xxx series without defects in the weld zone except for certain welding conditions with an insufficient heat input. The microstructures of welds have dynamic-recrystallized grain similar to stir zone in FSW weld. For sound joints without defects, at the rotation speed of 700 rpm with different welding speeds, the tensile strengths of the Stir Zone(SZ) were almost the same, 80% of those of the base metal. (JIS Z 2201)

• 대한기계학회논문집A
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• 제36권11호
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• pp.1335-1343
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• 2012

논문은 위상최적화와 치수최적화 해석기법을 이용한 샌드위치 복합재와 알루미늄 압출재로 구성되는 하이브리드 철도차량 차체 구조물의 경량 모듈화 설계에 관한 연구이다. 위상최적설계는 초기설계단계에 차체 구조물의 최적의 재료적용부위를 선정하기 위해 사용되었으며, 치수최적화설계는 하이브리드 차체 구조물의 최적 설계 변수를 찾기 위해 사용되었다. 이때, 최적화해석은 일계법과 부분문제근사법을 사용하였다. 위상최적설계해석을 통해 차체 구조물의 강성 및 제작성을 향상시키기 위한 언더프레임, 로우 사이드 패널 모듈에 1차 부재인 알루미늄 압출재의 적용이 적절하고, 샌드위치 복합재는 무게를 최소화하기 위한 2차 부재로서 루프 및 미들 사이드 패널 모듈에 적용이 적합하다는 결론을 얻었다. 또한, 알루미늄 압출재와 샌드위치 복합재로 구성되는 하이브리드 차체 구조물의 무게는 샌드위치 복합재로만 만들어진 차체 구조물과 비교하여 최대 17.7%까지의 경량화 효과를 얻을 수 있음을 확인하였다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2005년도 춘계학술대회 논문집
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• pp.453-458
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• 2005

Weight minimization of double-deck train carbody is imperative to reduce cost and extend life-time of train. It is required to decide 36 thickness of aluminum extruded panels. However, the design variables are two many to tract. moreover, one execution of structural analysis of double-deck carbody is time-consuming. Therefore, we adopt approximation technique to save computational cost of optimization process. Response surface model is used to apporximate static response of double-deck carbody. To obtain plausible response surface model, orthogonal array is empolyed as design of experiment(DOE). Design improvement by approximate model-based optimization is described. Accuracy and efficiency of optimization by using response surface model are discussed.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2002년도 춘계학술대회 논문집
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• pp.364-369
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• 2002

The purpose of this paper is to introduce the concept design and the structural strength of the double-deck rolling stock vehicle. Aluminum is very useful material for the carbody structure due to its characteristic of light weight. Large alumillum extrusion profiles(panels) have toe of merits such as easy production of complicated shapes, reduction of welding and cutting lines, and cutting down the labor cost. AED type is being applied to the standard EMUs and the EMUs Kwangju subway in Korea. Light material recommended the double-deck rolling stock vehicle because the center of gravity of the train is higher and its weight is heavier than those of the normal vehicle. So we applied the technology of the large aluminum extrusion profiles(panels) to the double-deck vehicle. We performed the structural strength analysis and examined its safety.

• 한국철도학회:학술대회논문집
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• 한국철도학회 1998년도 창립기념 춘계학술대회 논문집
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• pp.401-407
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• 1998

Recently, as the railway vehicles become speedy and massive, the collision is being regarded as an important factor for the assessment of safety for passenger. And the study of collision is being in progress more actively in advanced nations. In this study, the collision analysis is performed by using non-linear dynamic finite element program PAM-CRASH. The carbody used in analysis is made of Aluminum AL6005A to realize lightweight, and designed and manufactured by DHI (Daewoo Heavy Industry) lately. For the accuracy of the result in the practical collision, the experiment of material properties has been performed. The result of the analysis shows the underframe of rolling stock is the most important part as a collision energy absorbing structure. Further study is needed for optimal design which enables the carbody shell structure to disperse absorbing energy adequately.

• 한국철도학회논문집
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• 제2권3호
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• pp.54-60
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• 1999

In this paper, design and construction process for the standardized electric motor car according to standard specification is described. Aluminum extrusion profiles and power and control system made domestically are used in the electric motor car. Also, plug-sliding door system for noise reduction and automatic train control system are developed and applied. Through the development of the electric motor car, most electric and control systems can be substituted by domestic standard systems, and safety and reliability of electric motor cars can be secured.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2002년도 추계학술대회 논문집(II)
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• pp.870-875
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• 2002

The weight saving that results from the substitution of aluminum alloy for steel may be used to provide reduced energy consumption and labor cost due to simplified manufacturing process and improved vehicle performance. Because of these advantages, foreign advanced rolling stock manufacturing companies have been using aluminum alloy for bodyshell manufacturing. In this research, the comparison between FE analysis and actual load test results is performed for aluminum extrusion bodyshell, which is manufactured by Rotem Company. And the results show that the aluminum carbody structure satisfies the strength and stiffness requirements. Commercial FE analysis code and specially designed test equipment are utilized for the structural analysis and the static load test of bodyshell respectively.

• 대한기계학회논문집A
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• 제35권2호
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• pp.213-221
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• 2011

알루미늄 재질의 도시철도차량 차체의 경량화를 위해 이중 판재구조로 이루어진 철도차량용 알루미늄 압출재의 최적설계를 수행하였다. 위상최적설계 기법을 이용하여 알루미늄 차체에서 가장 큰 중량을 차지하는 하부 프레임 베이스 플레이트의 경량화된 위상을 도출하였고, 이를 기반으로 압출재 부재별 치수 최적화를 수행하였다. 하부 프레임 다음으로 큰 중량을 차지하는 측면 프레임 압출재에 대해서는 치수 최적화를 통하여 경량설계를 수행하였다. 최적설계안과 현재 설계의 최대발생응력과 최대 변형량을 비교하여 최적설계결과의 타당성을 검증하였다. 이 과정을 통하여 언더프레임과 사이드프레임의 중량을 현재보다 평균 12% 줄일 수 있었고, 차체 전체로는 8.5%의 경량화 효과를 얻었다.