• 한국철도학회:학술대회논문집
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• 한국철도학회 2002년도 추계학술대회 논문집(II)
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• pp.904-909
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• 2002

This paper contains the tension-tension and the tension-tension bearing fatigue characteristics of glass fabric/phenol composite laminates. The experimental results show that the bearing fatigue characteristics of the material is so excellent compared with the simple tension fatigue characteristics, that there are no needs of additional strengthening for mechanical joint parts when the parts are properly designed. The experimental data are also compared with the results of glass fabric/epoxy composite laminates.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2002년도 proceedings of the second asia international conference on tribology
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• pp.111-112
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• 2002

The influence of aerated oil on a high-speed proceeding bearing is examined by using the classical thermohydrodynamic lubrication theory coupled with analytical models for viscosity and density of air-oil mixture in fluid-film bearing including the live surface tension of aerated oil. Convection to the walls and mixing with supply oil and re-circulating oil are considered. The considered parameters for the study of bubbly lubrication are oil aeration level, air bubble size and shaft speed. The results show that, if the live surface tension is considered, the effect of air bubbles on the bearing load capacity is reduced due to temperature engagement comparing with that under the condition of a constant surface tension.

• KSTLE International Journal
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• 제2권2호
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• pp.103-113
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• 2001

The influence of aerated oil on high-speed journal bearing is examined by classical thermohydrodynamic lubrication theory coupled with analytical models for viscosity and density of air-oil mixture in fluid-film bearing. Convection to the walls and mixing with supply oil and re-circulating oil are considered. The live oil surface tension is considered as functions of temperature, API gravity and air volume ratio. With changing eccentricity ratio, it is investigated the effects of air bubbles on the performance of a high-speed plain journal bearing. Just at the moderate eccentricity ratios, even if the involved aeration levels are not so severe and the entrained air bubble sizes are not so small, it is found that the bearing load and friction farce may be changed so visibly for the high speed bearing operation.

• 한국기계가공학회지
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• 제11권5호
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• pp.21-28
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• 2012

This study analyzes about automotive engine tension bearing through the structural analyses of fatigue and vibration. Maximum equivalent stress is shown at the lower of tensioner. Among the cases of nonuniform fatigue loads, 'SAE bracket history' with the severest change of load becomes most unstable but 'Sample history' becomes most stable. In case of 'Sample history' with the average stress of 0 to $-10^{6}MPa$, the possibility of maximum damage becomes 3%. This stress state can be shown with 6 times more than the damage possibility of 'SAE Bracket history' or 'SAE transmission'. The structural result of this study can be effectively utilized with the design of tension bearing by investigating prevention and durability against its damage.

• Steel and Composite Structures
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• 제9권2호
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• pp.173-189
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• 2009

This paper presents a study on the behavior and design of bolted stainless steel plates under in-plane tension. Using an experimentally validated finite element (FE) program strength of stainless steel bolted plates under tension is examined with an emphasis on plate bearing mode of failure. A numerical parametric study was carried out which includes examining the behavior of stainless steel plate models with various proportions, bolt locations and in two different material grades. The models were designed to fail particularly in bolt tear-out and material piling-up modes. In the numerical simulation of the models, non-linear stress-strain material behavior of stainless steel was considered by using expressions which represent the full range of strains up to the ultimate tensile strain. Using the results of the parametric study, the effect of variations in bolt positions, such as end and edge distance and bolt pitch distance on bearing resistance of stainless steel bolted plates under in-plane tension has been investigated. Finally, the results obtained are critically examined using design estimations of the currently available international design guidance.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2004년도 춘계학술발표대회 논문집
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• pp.258-261
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• 2004

This paper contains the tension-tension, the tension-tension bearing and the tension-tension steel bolt joint fatigue characteristics of glass fabric/phenol composite laminates. The experimental results show that the bearing and the steel bolt joint fatigue characteristics of the material is so excellent compared with the simple tension fatigue characteristics, that there are no needs of additional strengthening for mechanical joint parts when the parts are properly designed.

• 한국정밀공학회지
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• 제19권3호
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• pp.95-100
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• 2002

Built-in Eccentric Bearing-Torsional Spring (BEBTS) type Automatic Belt Tension Unit (ABTU) is one of typical belt tension units. The BEBTS type ABTU system frequently experiences torsional vibration about its pivot due to the variation of belt tension. However, it is very difficult to analyze the rotational (or torsional) vibration of the ABTU because the exciting moment varies according to the change of belt tension. To get over this difficulty, in this paper. the ABTU was simplified as 1-DOF translational motion model in the tangential direction. Its equation of motion was derived and solved. The time history and frequency responses were computed and examined for three of BEBTS type ABTUs which are made by different manufacturers but the tame kind.

• 한국추진공학회지
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• 제1권1호
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• pp.111-121
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• 1997

본 연구에서는 탄소/에폭시 복합재료의 기계적 결합부위의 결합강도 예측을 위한 구조해석과 실험을 수행하였다. 복합재료 구조물의 Joint설계에 있어 베어링 파괴는 대단히 중요한 파괴형태 중하나이다. 그래서 본 연구에서는 베어링 파괴를 해석적으로 예측하고 실험적으로 확인하였다. 순수인장 파괴(Net Tension Failure)와 베어링 파괴(Bearing Failure) 실험을 위해서 각각 두 가지 형상의 시편을 선택하였다. 기계적 결합강도 예측에 사용된 방법은 특성길이(Characteristic Length)법과 연관시킨 Yamada-Sun 파괴기준(Failure Criterion)과 Tsai-Hill 최대일 이론이다. 그리고 인장특성길이와 압축특성길이는 실험을 통하여 얻어지며, 특히 압축특성길이 결정은 최근에 착안된 베어링파괴 실험으로부터 결정하였다. 위와 같은 예측 방법을 준등방성(Quasi-Isotropic) Carbon/Epoxy HT245/RS3232에 적용하였다. 연구결과, 이론적인 복합재료 파괴예측이 실험결과와 잘 일치함을 확인할 수 있었다.

• Steel and Composite Structures
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• 제28권2호
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• pp.167-177
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• 2018

In order to investigate mechanical properties in the core area of Square Hollow Section(SHS) column connection with external stiffening ring, four specimens were tested under the static tension load. The failure modes, load-displacement curves and strain distribution were analyzed to study the mechanical properties and the load transfer mechanism of the core area of connections. The connections behave good ductility and load-bearing capacity under the static tension load. Parametric analysis was also conducted, in which the thickness of steel tube, extended width and thickness of the stiffening ring were considered as the parameters to investigate the effects on mechanical properties of the connections. Based on the experimental results, an analytical method for the bearing capacity of connection with external stiffening ring under the static tension load was proposed. The theoretical results and the experimental results are in good agreement, which indicates that the theoretical calculation method of the bearing capacity is advisable.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2013년도 춘계학술대회 논문집
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• pp.1213-1214
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• 2013