• 제목/요약/키워드: Heavy machinery

검색결과 317건 처리시간 0.03초

Recent Advances in Dry-bag CIP Equipment

  • Kishi, Yoshikazu;Miyashita, Yasuhide;Manabe, Yasuo;Fujikawa, Takao
    • 한국분말야금학회:학술대회논문집
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    • 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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    • pp.1259-1260
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    • 2006
  • Intensive technological research on the Dry-bag CIP equipment was carried out to improve the dimensional accuracy and the productivity. The rubber mold design technology using FEM simulation during pressing was introduced, in order to achieve higher dimensional preciseness, and criteria for the selection of the In-line type or Off-line type, were established based on the powder flowability index proposed by Carr. Based on these research results, high productivity Off-line Dry-bag CIP equipment, which can realize good dimensional accuracy with high productivity, was developed even for non-granulated powders with poor packing density.

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건설기계용 유압실린더 위치 제어시스템의 성능개선에 관한 연구 (A study on performance improvement of position control system in hydraulic cylinder for heavy construction machinery)

  • 한석재;박성환;이진걸
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
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    • pp.1450-1454
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    • 1996
  • Even though digital control type high speed solenoid valve is a little inferior to analog control type servo valve and proportional control valve in performance, it is cheap and has secure performance against pollutant and simple control circuit. But high speed solenoid valve is hardly used for heavy machinery instead of servo valve or proportional control valve that is used in severe condition because the valve itself is small capacity and it shows wide dead zone during on-off control and chattering of hydraulic cylinder by chattering of pressure. It is desirable to use low-priced and strong pollutant resistant high speed solenoid valve for obtaining reliability of operation from severe working condition because it isn't necessary to acquire response characteristic of high frequency when we consider the characteristic of heavy machinery operation. In this study, PWM control algorithm for pilot pressure control of large capacity pilot operating valve will be used for precision position control of heavy machinery hydraulic cylinder. Not only cost reduction of main control valve but also high reliability of heavy machinery in severe condition can be obtained by using this pilot operating spool valve with high speed solenoid valve.

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JAVA-BASED SIMULATION FOR DEVS

  • Bai, Tao;Zeng, Jianchao;Wang, Meng
    • 한국시뮬레이션학회:학술대회논문집
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    • 한국시뮬레이션학회 2001년도 The Seoul International Simulation Conference
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    • pp.349-353
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    • 2001
  • There are many excellent characters of Java-based simulation compared with existing ones in the respect of running on the Internet/Web, reuse, integration and etc.. In this paper, the main idea of design and realization of Java-based modeling and simulation software for DEVS will be discussed in detail.

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Hull Structural Design of A 300,000 DWT Double Hull VLCC

  • Bong, Hyon-Soo;Yoo, In-Sang;Oh, Yeong-Tae
    • Journal of Hydrospace Technology
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    • 제1권1호
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    • pp.89-110
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    • 1995
  • The enactment of OPA90 (Oil Pollution Act of 1990) in the USA and the consequent moves by IMO(International Maritime Organization) to introduce new Regulations for the design of oil tankers led the oil transportation industry to undergo a period of big change. This resulted in the introduction of double hull tankers. This paper introduces the design for the 300, 000 DWT double hull VLCC of World-Wide Shipping Agency Pte Ltd. in Hong Kong, which is the first of this type constructed by Daewoo Shipbuilding & Heavy Machinery Ltd.(DSHM). The characteristics of the compartment and structural arrangement of this vessel are briefly described, and the scope of structural analysis is illustrated. In addition, the merits/demerits of different crosstie arrangements are described in the appendices.

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중전기기(重電器機) 연구개발 현황(現況)과 미래동향(未來動向) (The Present and Future Tendency in Electric Machinery)

  • 김종구;김익모;최영찬;김세창
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2000년도 추계학술대회 논문집 학회본부 C
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    • pp.613-615
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    • 2000
  • We explained the present and future tendency in the electric machinery research and development status. Being started WTO system and in the Infinite competitiveness, we hope that this paper will be helpful to strengthen competitiveness of our electric machinery industry.

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The development of a wear resistant hard-metal tappet in diesel engines

  • Shim, D.S.;Song, K.C.;Kim, K.W.;Cho, J.W.
    • 한국윤활학회:학술대회논문집
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    • 한국윤활학회 2002년도 proceedings of the second asia international conference on tribology
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    • pp.401-402
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    • 2002
  • Diesel engines have many sliding parts with solid body contact. For example, a piston-ring and a cylinder bore, a valve and a valve-seat, a cam and a valve tappet. These parts have a severe wear problem. during engine life times. During these times, the valve tappet has abnormal wear such as scuffing and pitting due to a high hertzian contact stress between the cam and the tappet. Excessive wear problems frequently occur to both the cam and the tappet. To solve these problems, we developed an advanced wear resistant tappet. The developed tappet consisted of a hard-metal wear part and a steel body. To increase a bonding strength, those two parts, were directly bonded to each other. Also to decrease a bonding temperature, we developed the composition of Ni-binder materials in the hard metal. To estimate the wear characteristics of the newly developed tappet, we performed wear tests and engine dynamo tests in order to compare them with a conventional Fe-base tappet. As a result, the newly developed tappet has better wear characteristics than those of the conventional tappet. In addition, we performed a 100,000km field-test, and the newly developed tappet showed much improved wear resistance.

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GIS 절연파괴 위치 추정 시스템의 현장 적용 연구 (Field Study for Location Estimation System of Dielectric breakdown in Gas Insulated Switchgear)

  • 민병운;이정복;김중표;김정한
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2015년도 제46회 하계학술대회
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    • pp.543-544
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    • 2015
  • GIS(Gas Insulated Switchgear:가스절연 개폐장치)는 절연성능이 뛰어난 $SF_6$가스로 절연되어 초고압 전력의 제어(차단,투입)를 담당하는 중요한 장치이다. GIS는 절연성능을 검증하기 위하여 현장 운전전에 공장검수시험(내전압시험)과 현장 가압 시험을 수행한다. 이 때 GIS의 조립/운반/설치의 오류로 인한 절연성능 저하로 절연파괴(내부아크)가 발생될 수 있다. 그러나 GIS는 $SF_6$가스로 밀폐되어 있어 절연파괴를 정확히 알 수 없을 뿐만 아니라 사고 위치를 확인하기 어렵다는 단점을 가지고 있다. 따라서 본 논문에서는 이런 문제를 해결하기 위하여 GIS 내부에서 발생되는 사고를 신속하게 탐지하고 위치를 정확하게 표정할 수 있도록 개발된 GIS 절연파괴 위치 추정 시스템의 현장 적용연구를 수행하였다. 이를 통해 GIS 절연파괴 위치 추정 시스템의 성능을 확인하였다.

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센서기반 지능형 아크 용접 로봇 시스템의 동향 (Trends of Sensor-based Intelligent Arc Welding Robot System)

  • 정지훈;신현호;송영훈;김수종
    • 제어로봇시스템학회논문지
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    • 제20권10호
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    • pp.1051-1056
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    • 2014
  • In this paper, we introduce an intelligent robotic arc welding system which exploits sensors like as LVS (Laser Vision Sensor), Hall effect sensor, voltmeter and so on. The use of industrial robot is saturated because of its own limitation, and one of the major limitations is that industrial robot cannot recognize the environment. Lately, sensor-based environmental awareness research of the industrial robot is performed actively to overcome such limitation, and it can expand application field and improve productivity. We classify the sensor-based intelligent arc welding robot system by the goal and the sensing data. The goals can be categorized into detection of a welding start point, tracking of a welding line and correction of a torch deformation. The Sensing data can be categorized into welding data (i.e. current, voltage and short circuit detection) and displacement data (i.e. distance, position). This paper covers not only the explanation of the each category but also its advantage and limitation.