• 제목/요약/키워드: Crown Roll

검색결과 37건 처리시간 0.036초

냉연 작업인자와 edge drop의 상관관계 (The Relaion between Cold Rolling Factors and the Edge Drop)

  • 여원구;황상무;정제숙;김종근
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2001년도 추계학술대회 논문집
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    • pp.142-146
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    • 2001
  • In this study, it was investigated the influence of cold rolling factors on the edge drop. Edge drop was highly affected by the shape of work roll, the amount of work roll shift and the crown of hot strip, but the effect of bending force at the front stand was relatively small. The used numerical model was examined by comparing to the result of measured field data, and it showed a qualitative agreement with each other.

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HDD용 에어베어링 슬라이더의 강건설계에 관한 연구 (A Robust Design Study of Air Bearing Slider for HDD)

  • 전규찬;장동섭;좌성훈
    • Tribology and Lubricants
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    • 제16권4호
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    • pp.247-252
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    • 2000
  • As the demand for higher areal recording densities requires a lower flying height of the slider, the variation of the flying height of the slider during drive operation becomes of great concern. The variation of the flying height is closely related with the slider design parameters such as air bearing shape, cavity depth, shallow step depth, crown, camber, pitch offset, roll offset, gram load, and so on. The objective of this work is to optimize the cavity depth and the shallow step depth, which are the control factors in air bearing design, using Robust Design method. It was found that the shallow step depth was statistically significant in affecting the variation of flying height, therefore the level of the shallow step depth should be chosen to minimize the variation of flying height.

강판 열간압연의 기술개발 동향 (Recent Trend in Hot Rolling Technology of Steels)

  • 신수철
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 1999년도 제3회 압연심포지엄 논문집 압연기술의 미래개척 (Exploitation of Future Rolling Technologies)
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    • pp.3-9
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    • 1999
  • The recent technical trend in hot rolling of steel can be described as process and product technologies which have been progressed with modern mill equipment and computers. Precise gauge and width control can be achieved by up-to-date control methods such as AGC and AWC systems. Roll benders and various shape control systems enabled high quality flatness and crown control. Mills can produce higher tensile materials by new process based on process metallurgy. The use of high speed steel rolls and on line roll grinders make the schedule free rolling easier which results in cost saving. Process itself goes toward continuous and simple flow type which has lower operation. Endless rolling and strip casting are examples of the trend. Materials with higher tensile strength and various functions have been developed in last years to meet the customer's needs and this trend will continue.

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압연판의 두께 정밀도에 관한 연구 (Study on the thickness precision of rolled sheets)

  • 김동원;윤상건
    • 대한기계학회논문집
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    • 제11권5호
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    • pp.837-845
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    • 1987
  • 본 연구에서는 Tozawa의 이와 같은 근사적 3차원 해석법을 검토하여 그 특징 을 살피고 판나비, 판두께, 압하율의 변화가 삼차원변형역과 평면변형역의 최적 경계 면 위치에 미치는 영향을 고찰하고자 한다.

Development of The New Shape Control Algorithm with The Strip Thickness Decoupling in Hot Strip Mill

  • Dukbum Shin;Kim, Jongcheol;Sangchul Won
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2001년도 ICCAS
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    • pp.175.2-175
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    • 2001
  • The strip profile and shape control is one of the most important technologies in Hot Rolling Mill System. Because the unbalance of strip´s shape and wave appearance between stands has a bad effect on Hot Rolling Mill System by making the inferior thickness, strip´s damage and so forth in factories. Many competition Plate Mill introduced shape control system, for example, pair cross-mill, work roll bender, which includes shape measuring instruments and shape control mathematical models. Shape meter, which is equipped for flatness, only does feedback control at the top of coil. And, for crown, we depend on initial setup value and there is no feedback control. Therefore we predict the shape of strip using rolling pressure, bender force and tension of inter-stand in ...

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아까시잎혹파리, Obolodiplosis robiniae (Diptera: Cecidomyiidae) 연간 밀도변동과 아까시나무 수관 내 분포 (Seasonal Fluctuation and Distribution of Obolodiplosis robiniae (Diptera: Cecidomyiidae) Within Crown of Robinia pseudoacacia (Fabaceae))

  • 이정수;정유미;최광식;김일권;권영대;전문장;신상철;최원일
    • 한국응용곤충학회지
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    • 제48권4호
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    • pp.447-451
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    • 2009
  • 아까시잎혹파리(Obolodiplosis robiniae(Haldeman))는 아까시나무(Robinia pseudoacacia Linnaeus(Fabaceae)) 잎 가장자리에 혹을 형성하는 혹파리과 해충으로 북미대륙 동부가 원산으로 국내와 일본에 2002년 유입되었음이 보고되었다. 본 연구는 아까시잎혹파리의 계절별 밀도변동과 수관 내 분포를 구명하기 위하여 수행되었다. 밀도조사는 경기도 오산시 수청동과 시흥시 대야동의 아까시숲에서 5월부터 8월까지 조사되었으며 아까시잎혹파리 밀도는 잎당 유충수를 기준으로 추정되었다. 아까시잎혹파리 세대 수는 지역별로 차이가 있어, 오산에서는 3세대, 시흥에서는 2세대가 관찰되어 국내에서는 최대 3세대가 발생할 수 있음을 보여주었다. 오산지역 아까시나무내 아까시잎혹파리 유충 밀도분포는 수관 상부가 수관 중간 부분과 하부보다 높았다. 시흥지역 아까시나무의 수관 하부 바깥쪽 밀도가 안쪽보다 높았다. 아까시잎혹파리의 혹 당 유충수는 오산, 시흥에서 각각 $3.3{\pm}0.1$, $2.8{\pm}0.1$ 마리였다.

고대 로마 신화에 등장한 신들의 복식 연구 (A Study on the Costume of the Gods in the Ancient Roman Myths)

  • 임상임;추미경
    • 한국의류학회지
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    • 제25권5호
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    • pp.945-956
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    • 2001
  • The costume for gods in the Ancient Roman myth was studied by examining in the embossed-carving, sculptures, mural-painting and various documents of the period. The clothes item, hairstyle, symbol & ornaments and shoes of the gods in the Roman myths were analyzed to understand the formative process in the religious costumes, and results are as follows. First, the costumes for male gods are the same as those for ordinary men lived in ages, including toga, paludamentum, tebenna, tunica. The costumes for female gods are also the same as those for ordinary women lived in ages, including stola, palla, tunica. Second, the hairstyle of male gods is short curled-hair, twisty roll-up hair and braid long-hair due to the influence of Etrurian in the early days. Another hairstyle is appeared in form of the laurelled-crown. The hairstyle of female gods is curled long-hair, chignon style and braid roll-up hair decorated with hairband. Third, the symbol & ornaments which represent the responsible possession of male gods, are appeared in beard, a stick of the message, arrow-case, offering-dish, antlered-glass, shield, spear-handle, as the superhuman forms, such as the lightning shape. For female gods they are is appeared plastron, a stick of the message, flower. some female gods wear necklace, foot-ring, bracelet. Fourth, male gods wear shoes in forms of sandal, buskin, boots, but all female gods are in barefoot. It could be explained by the fact that a man-centered society in the ancient roman is reflected in the world of gods. As mentioned, Gods costume in Roman myths was very similar to or nothing different from the ordinary peoples in Rome. However, they used corps, sacrifices or sepcific symbols depending on the fields that they were responsible for in order to be distinguished from the ordinary people. This is the result from the peoples expression that they should keep a close relationship with Gods hoping to be protected, and rely on them under whatever circumstances.

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