• 베이커리
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• no.7 s.336
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• pp.72-74
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• 1996

• Proceedings of the KWS Conference
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• 1993.05a
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• pp.31-31
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• 1993

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2012.06a
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• pp.223-223
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• 2012

• Composites Research
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• v.29 no.3
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• pp.111-116
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• 2016

The tilting pad journal bearing for the turbo compressor application has a role to support high speed and heavy loading rotor. White metal has been widely used for the bearing material but the conventional bearing is immediately suspended and induces serious serious damage to the rotor under the unexpected oil cut situation or the insufficient oil film formation. The carbon fiber reinforced composite having high specific stiffness, specific strength and excellent tribological characteristics can solve these seizure problems. In this work, the study on the durability of high thermal resistance carbon fiber/epoxy composite tilting pad journal bearing under oil cut situation was conducted. The material properties of the composite materials including tensile, compressive and interlaminar properties were measured at room and high temperature of oil cut situation. To investigate the possibility of failure of composite tilting pad journal bearing under oil cut situation, the stress distribution of the composite bearing was analyzed via finite element analysis and the Tsai-Wu Failure index was calculated. To verify the failure analysis results, the oil cut tests for the composite tilting pad journal bearing were conducted using industrial test bench.

• Journal of Advanced Marine Engineering and Technology
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• v.19 no.4
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• pp.61-71
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• 1995

Nowadays the thin-walled metal bearing, which is made seperately from the bearing housing and has the ratio of wall thickness/bearing diameter being less than 1/30, are used in many newly developed large-sized slow speed diesel engines for the purpose of upgarding lubication performance and easy maintenance according to the trends of increasing output per cylinder and lowering engine speed. The type of this bearing has been used generally in many small-sized high speed engines applied for automobile, high speed craft and industrial power generation systems since 1950s. But the tranditional thick-walled bearings, whice are linned white metal on the bearing housing directly, have been installed on the large and slow speed engines until 1990s due to the easy manufacturing procedures. In this study we have calculated optimum dimensions of the metal bearing, fabricated special zigs for crush measurement, model test machine, 2 sets of specimens.(crosshead pin bearing, $\phi$818*552*20mm) for B & W 6S70MC(20, 940*88rpm), and evaluated metal constact phenomena of white metal, its friction coefficient, temparature rise through the model test and field performance test.

• Journal of the Society of Naval Architects of Korea
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• v.41 no.3
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• pp.35-40
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• 2004

Since the scale of vessels is growing up recently, some troubles between the shaft and after bush bearing are frequently reported. Generally, mean pressure on bush bearing is used as a design criterion. However, in some case of the long bearing such as after bush bearing of the propulsion shaft, it might be liable to be locally under high pressure. As for the main engine bearings and the intermediate shaft bearing, it is reasonable to take the mean pressure as a design criterion. But, in case of after bush bearing, it is not sufficient because of the possibility of high pressure caused by local contact. In this study, Hertzian contact condition was applied to evaluation of the local pressure for after bush bearing. To reduce the local maximum pressure, the height of the after bush bearing was controlled. It was found that local maximum pressure could be reduced effectively by taking a partial slope on the white metal of the aft bush bearing.

• The monthly packaging world
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• s.358
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• pp.65-70
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• 2023

(사)한국패키지디자인협회(회장 강부연)가 '2022 제31회 대한민국패키지디자인대전'의 수상작을 발표했다. 이 공모전은 국내 유일의 포장디자인 공모전으로 대학생부문과 일반부문으로 나뉘어 독창성, 상품의 외관, 기능, 소재, 경제성 등을 심사하여 선정했다. 이번 공모전은 포장디자인 분야 디자이너들의 많은 관심과 호응으로 대학생부문은 10개 대학 177점, 일반부문은 30개 업체 71점이 우수 포장디자인 제품으로 선정되어 포장 디자인의 중요성을 통해 위상을 다시 한 번 드높였다. 출품작들의 주목할 점으로는 친환경 트렌드를 반영한 다수의 제품들이 출품되었다는 것이다. 특히, 코로나19 장기화로 인한 소비패턴과 생활의 변화에 따른 트렌드를 반영한 포장디자인 제품이 대거 출품되어 이목을 끌었다. 올해 '대상'은 서울우유협동조합 골든저지밀크 제품이 선정되었으며, 이외 은상으로 업사이클링에 포커스를 맞춘, (주)신원인팩/페어플레이파머스 농업회사법인 사과 부산물을 활용한 친환경 사과트레이 [업사이클링 : APPLE CLAM(애플클램), 화이트와 메탈릭 컬러 매치를 통한 고급화 이미지를 극대화시킨 디자인 (주)아워홈 AMORIS Charcutrie 등 우수 포장디자인으로 선정되었다. 본지에서는 공모전 일반부문 본상 수상작들을 통해 패키지디자인의 최신 동향을 살펴보도록 한다.

• Tribology and Lubricants
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• v.34 no.3
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• pp.84-92
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• 2018

Bearings are essential for reducing vibration and wear, in order to achieve high durability and increase longevity. White metal treatment of tilting pads via centrifugal casting method has the possibility of increasing durability. However, this manufacturing method has drawbacks such as long processing time, high defect rate, and harmful health effects. Laser cladding deposition technique is a powerful method that can address these issues by decreasing the processing time and providing good adhesion. In this study, we suggest optimum conditions for laser cladding deposition that can be used in industrial applications. We deposited a soft white metal layer on SCM440 that is primarily used in shafts to minimize wear of bearing pads. During the laser deposition process, we controlled factors such as laser power, powder feed rate, and laser head speed to determine the optimum conditions. In addition, we measured the hardness using micro Vickers, and performed field emission scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffraction, and friction tests to investigate the mechanical properties and surface characteristics for different parameters. Based on the experimental results, we suggest that laser power, powder feed rate, and laser head speed of 1.3 kW, 2.5 rpm, and 10 mm/s, respectively, constitute the optimum conditions for producing white metals using laser cladding.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.9
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• pp.480-485
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• 2017

The main reason for the heat induced accidents occurring at the after stern tube journal bearing is the excessive local pressure caused by the deflection of the propulsion shaft due to the propeller loads. It is expected that the contact area could beenlarged and the local pressure reduced accordingly by using a lining material having alow Young's modulus instead of the existing white metal. The purpose of this work is to investigate the characteristics of the pressure distribution and determine the allowable pressure value in the case where bearing products made of materials having a low Young's modulus are used. In this study, the propeller loads, heat effect, and hull deflection are considered in the evaluation of the local pressure of the ship propulsion shaft. Also, the Hertzian contact condition was applied. From the analysis results in the case where a lining material with a low Young's modulus was used, it was found that a robust design could be achieved and the local pressure could be reduced effectively independent of the load conditions. It will be possible to producenew products made of materials having a low Young's modulus if the manufacturer confirms the performance specifications drawn by this study.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.7
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• pp.391-398
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• 2020

If the lost energy produced by a propeller can be partially recovered, the propulsive efficiency can be increased, and the fuel consumption reduced. The devices installed for this purpose are called Energy Saving Devices, of which the Contra-Rotating Propeller system is one of the most effective devices. The first problem to be solved to install the Contra-Rotating Propeller system on a large ship is that the mean pressure generated in the journal bearing needs to meet the design criteria of the classifications. In Korea, however, the practical use is being delayed because it cannot overcome this step. The next step is to lower local pressure to increase the reliability. In this study, to solve the mean pressure problem as the first step of practical use, a product carrier with a short stern shape was selected to reduce the weight of the shafting system, and a suitable shafting-system design plan was proposed. Shaft analysis confirmed that the mean pressure of 0.8 MPa (8 bar), which is a design criterion of the classifications for a journal bearing lining material (white metal), was satisfied. In addition, the necessity of reducing the local pressure was also confirmed.