• 제목/요약/키워드: Roll Bending

검색결과 116건 처리시간 0.024초

물리적 처리가 잉크젯 코팅지 생산 과정 중에 발생되는 컬에 미치는 영향 (Effect of Physical Treatments on Curl in Inkjet Coated Paper During Papermaking)

  • 임연주;남원석;백기현
    • 펄프종이기술
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    • 제36권2호
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    • pp.39-46
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    • 2004
  • In this paper, the effects of roll diameter and storage time in roll form, bending method and relative humidity on curl in copy paper and inkjet coated papers are investigated. In copy paper, more MD curl is showed at smaller roll diameter and the extension of bending time. However CD curl is hardly influenced by roll diameter and bending time. At high relative humidity, especially CD curl largely reduces. All inkjet coated papers without the primary or the secondary back coating during papermaking show the increase in MD curl and slight decrease in CD curl by MD bending regardless of the winding methods(TSO, TSI). The water spray as back coating results in the remarkable reduction of CD curl regardless of the winding methods. Drying on flat dryer after spraying the moisture on back side display the most excellent effect on the reduction of CD curl.

자동차 연료탱크용 링 플레이트의 신 제조공법 (A New Manufacturing Process for the Ring Plate of Automotive Fuel Tank)

  • 채명수;임용희;서영성;박춘달;김영석
    • 소성∙가공
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    • 제17권5호
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    • pp.350-355
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    • 2008
  • Currently, in the automotive industry, the efforts to reduce the manufacturing cost by changing the manufacturing process are continually performed. In this paper, we proposed a new manufacturing process, the roll bending process of a ring plate of automotive fuel tank instead of conventional press blanking process to reduce material loss and manufacturing cost. Finite element analysis was used to optimize the roll bending process to assure rectangular cross-section of the ring plate. Also, spring-back analysis after the roll bending process was performed and dimension of the bending die considering spring-back was analyzed. Finally, we verified a possibility for realization of the proposed method with prototypes.

고강도 차체부품 제작 기술에 대한 연구 (The Study of Manufacturing Technology for Front Side Member Lower)

  • 박상언;김동규;이규현;김광희;이문용
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2009년도 추계학술대회 논문집
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    • pp.293-296
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    • 2009
  • In roll forming process, a sheet metal is continuously progressively formed into a product with required cross-section and longitudinal shape, such as a circular tube with required diameter, wall-thickness and straightness, by passing through a series of forming rolls in arranged in tandem. In recent years, that process is often applied to the bumper rail in the automotive industries. In this study, a optimal front side member manufacturing technology, model deign and proper roll-pass sequences can be suggested by forming number of roll-pass and bending angle. And also effects of the process parameters on the final shape formed by roll forming defects were evaluated.

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선체 곡판의 롤 굽힘 공정 변수 결정을 위한 가공 형상의 최적 근사 알고리즘 (An Algorithm on Determination of Process Parameters for Roller Bending of Curved Shell Plates)

  • 유철호;이장현;윤종성
    • 대한조선학회논문집
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    • 제44권5호
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    • pp.517-525
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    • 2007
  • This paper presents how to approximate an optimal shape of roll bending process in the fabrication of a curved shell plate. The roll bending process usually makes the cylindrical or conic shape from an initial flat plate. It means that the final shape is developable or its surface representation has zero Gaussian curvature. The fabrication shape is important in order to find process parameters of roil bending. An optimal concept is used to determine the developable fabrication shape which is in the closest proximity to the design surface or the given shell plate and is subject to developability. The results and the efficiency of this algorithm are evaluated by applying to some shell plates. Furthermore, the fabrication shape will be fundamental information for other process parameters of roll bending such as the vertical displacement of the center roller and the rolling directions.

후판 압연공정에서 선단부 굽힘 예측을 위한 롤 바이트 형상맵 기법에 관한 연구 (A Roll-Bite Profile Map Approach for the Prediction of Front End Bending in Plate Rolling)

  • 변상민;이재현;김상록
    • 소성∙가공
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    • 제20권4호
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    • pp.284-290
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    • 2011
  • The front end bending(FEB) behavior of material that usually occurs in plate rolling is investigated. In this paper, a rollbite profile map approach that systematically predicts the FEB slope is presented. It is based on the concurrent use of shape factors and reduction ratios to ensure an accurate value of the FEB and its slope. In order to obtain the unit roll-bite profile map, the FEB slope model was decomposed into a temperature deviation component and a roll-velocity deviation component. By mapping the results of a series of finite element analyses to the unit functions of the roll-bite profile map, it was possible to obtain a realistic prediction of the FEB slope applicable to an actual plate rolling process. Thereby, the usefulness of the present approach is clearly demonstrated.

점진적 롤 성형공정을 이용한 이중곡률의 금속판재 제작 및 정밀성형을 위한 형상 예측 (Manufacture of Doubly Curved Sheet Metals Using the Incremental Roll Forming Process and Prediction of Formed Shapes for Precision Forming)

  • 윤석준;양동열
    • 한국정밀공학회지
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    • 제21권9호
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    • pp.95-102
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    • 2004
  • A flexible incremental roll forming process has been developed by adopting the advantages of the incremental forming process and the roll forming process: i.e., inherent flexibility of the incremental forming process and continuous bending deformation of the roll forming process. It has an adjustable roll set as a forming tool composed of one upper center roll and two pairs of lower support rolls, which plays a key role during forming process. Through the experiments based on the various combinations of process parameters, it is shown that the incremental roll forming process is so effective as to manufacture various doubly curved sheet metals including concave-convex combination shapes in which there exists a line of inflection. The proposed relationship of the experimental parameters and the radius of curvature of the formed sheet boundary is found to be useful in prediction and control of the final shape.

비틀림 진동감쇠기용 슬리브 스프링의 제조 공정 해석 (A Process Analysis for Manufacturing the Sleeve Spring of the Torsional Vibration Damper)

  • 황범철;배원병;김철
    • 한국정밀공학회지
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    • 제26권12호
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    • pp.94-101
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    • 2009
  • In diesel engines, it is inevitable that the torsional vibration is produced by the fluctuation of engine torque. Therefore, it is necessary to establish preventive measures to diminish the torsional vibration. The sleeve spring type damper is one of the preventive measures for reducing the torsional vibration. In this study, 2-roll bending process was proposed to manufacture sleeve spring; The program to calculate the initial radius including springback effect was developed and the FEA method to analyze elasto-plastic problem was verified through analysis of 90 degree bending process. The elasto-plastic analysis of 2-roll bending process was carried out by the FEA method verified to set a new criterion, and the new process design parameter(contact angle) in the 2-roll bending process was proposed.

롤 포밍 공법을 이용한 고강도 차체 부품 제작 기술 개발 (Development of Manufacturing Technology for Center Floor Cross Member with Roll Forming Process)

  • 김동규;박상언;조국래;이규현;김광희;이문용
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2009년도 추계학술대회 논문집
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    • pp.297-300
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    • 2009
  • The roll forming process is often used to manufacture long, thin-walled products such as a pipe. The final cross-section is a comparatively simple open-channel, a closed tube section or a complex profile with several bends. In recent years, that process is often applied to the bumper beam in the automotive industries. In this study, a optimal Center Floor Cross Member manufacturing technology, model deign and proper roll-pass sequences can be suggested by forming number of roll-pass and bending angle, and also effects of the process parameters on the final shape formed by roll forming defects were evaluated.

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판재의 편평도 향상을 위한 교차압연에 관한 연구 (A Study on the Cross Rolling for Improvement of Flatness of Plate)

  • 남경오;서기석;노병래;홍성인
    • 소성∙가공
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    • 제14권1호
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    • pp.43-48
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    • 2005
  • The production of metal strip with uniform thickness and flatness are two important problems associated thin strip rolling. The thickness and flatness of strip are affected by the flattening of contact surface between strip and roll, the elastic recovery and the bending of roll. Especially, the flatness of the strip is greatly affected by bending deflection of roll. The roll must be designed considered the elastic deformation of roll. This study describes the measurement of thickness and flatness of strip and shows the crown roll for producing flat strip. But it is difficult to produce the crown roller. The cross rolling that is a simple method which can produce the flat strip is introduced and it is found the optimal cross angle for improvement of flatness of plate. These problems are solved by the MARC code on the basis of elastic-plastic material and the updated Lagrangian formulation.