• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2012년도 춘계학술대회 논문집
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• pp.905-906
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• 2012

• 한국자동차공학회논문집
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• 제15권5호
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• pp.160-164
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• 2007

An automotive wheel bearing is one of the most important components to guarantee the service life of a passenger car. The endurance life of a bearing is affected by many parameters such as material properties, heat treatment, lubrication conditions, temperature, loading conditions, bearing geometry, internal clearance and so on. Generally, a tapered roller bearing gives longer endurance life than that of an equivalent size ball bearing. Consequently, the application of taper bearing units will be increased for more compact design and extended warranty. In this paper, we derive the relation between loads and deformations of a taper bearing unit. On the basis of that, we calculate the endurance life of the taper bearing unit considering initial axial clearance.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2006년도 춘계학술대회 논문집
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• pp.434-437
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• 2006

Due to the shape of spindle with small diameter and heavy section, rapid cooling is difficult. It is difficult to fabricate the tapered wheel bearings with fine microstructure. Thus, their mechanical characteristics, such as yield strength and fatigue resistance, decrease. Producing the tapered wheel bearings with good workability during orbital forming after hot forging, hot forging process with several process parameters was optimized by means of statistical technique of Six-Sigma scheme. As a result, the lower heating temperature is, the lower the hardness and yield strength of forgings are. Also, the faster conveyer velocity is, the lower the hardness and yield strength of forgings are. To avoid therefore occurrence of the surface rupture during orbital forming, the heating temperature should be controlled as low as possible and the conveyer velocity should be controlled as fast as possible.

• Tribology and Lubricants
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• 제39권5호
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• pp.183-189
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• 2023

A bearing is a mechanical component that transmits rotation and supports loads. According to the type of rotating mechanism, bearings are categorized into ball bearings and tapered roller bearings. Tapered roller bearings have higher load-bearing capabilities than ball bearings. They are used in applications where high loads need to be supported, such as wheel bearings for commercial vehicles and trucks, aircraft and high-speed trains, and heavy-duty spindles for heavy machinery. In recent times, the demand for reducing the driving friction torque in automobiles has been increasing owing to the CO₂ emission regulations and fuel efficiency requirements. Accordingly, the research on the driving friction torque of bearings has become more essential. Researchers have conducted various studies on the lubrication, friction, and contact in tapered roller bearings. Although researchers have conducted numerous studies on the friction in the lips and on roller misalignment and skew, studies considering the influence of roller shape, specifically roller shape errors including lips, are few. This study investigates the driving friction torque of tapered roller bearings considering roller geometric uncertainties. Initially, the study calculates the driving friction torque of tapered roller bearings when subjected to axial loads and compares it with experimental results. Additionally, it performs Monte Carlo simulations to evaluate the influence of roller geometric uncertainties (i.e., the effects of roller geometric deviations) on the driving friction torque of the bearings. It then analyzes the results of these simulations.

• 대한기계학회논문집A
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• 제37권11호
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• pp.1323-1330
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• 2013

휠 로더는 다양한 작업이 가능한 건설장비 중의 하나로서, 기능적 다양성과 구조적 신뢰성 향상의 요구가 증대되고 있다. 휠 베어링은 로더의 수명을 결정하는 핵심부품 중 하나이며, 테이퍼 롤러 베어링이 사용되고 있다. 일반적인 베어링 수명은 하중과 회전속도로 계산되고 있다. 테이퍼 롤러 베어링의 초기 예압은 내구수명에 직접적인 영향을 미치는 중요한 인자이다. 본 논문은 테이퍼 롤러 베어링에 작용하는 하중, 회전속도, 열 변형에 따른 초기 예압량을 포함한 내구수명 및 예압특성 관계를 제시하였다. 사용온도가 $100^{\circ}C$라면, 상온에 비해 과다 예압 상태가 되며, 내구수명은 약 20.3% 감소하는 결과를 나타내었다.

• 한국자동차공학회논문집
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• 제22권4호
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• pp.46-54
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• 2014

The hollow design of a railway axle is one of the most effective methods to reduce the weight of an axle. However, the conventional hollow axle has the limitation of a lightweight design because it has the same bore diameter along the axial position. The new type of railway axle, the tapered inner surface railway axle, has a different inner diameter between the journal bearing seat and wheel seat. This design method is one way to increase the weight reduction possibility. The purpose of the present study is to establish and evaluate the design of the tapered inner surface railway axle. The case study and Finite Element Method(FEM) are applied to evaluate the strength of the lightweight railway axle according to the European Norm(EN 13103). Finally, the best design case for reducing the weight of the axle is drawn from the results of the case study.