• Tribology and Lubricants
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• 제22권1호
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• pp.47-52
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• 2006

It is very important to control pressure and flow rate distribution on each component of engine lubrication network. Sometimes many kinds of orifice are used to control flow rate in the hydraulic lubrication field. In this study orifices were adopted on the lubrication network to control oil flow rate distribution. And unsteady transient flow network analysis was carried out to find out the effects of orifices on the engine oil circuit system.

• Tribology and Lubricants
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• 제10권3호
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• pp.1-11
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• 1994

근년에 이르러 waste oil의 문제는 그 어느 때보다도 양이나 종류에 있어서 과거에 볼 수 없었던 만큼 심각한 양상을 나타내고 있다. 1992년도 한해동안 세계적으로 발생된 바 있는 폐윤활유의 양은 약 23,200 mega liter로 추정되고 있으며, 재정제에 의하여 recycle된 oil은 각국에 따라 차이점은 있으나 대략 수요량의 2~3%로서 이들의 합계량은 약 1,890 mega liter로 추정되고 있다. 한편 우리나라 waste oil의 발생량인 경우, 통계가 명확하지는 않지만 1993년도 한해동안 약 75만톤에 이를 것으로 추정되고 있는가 하면, 이 중 특정폐기물로 분류되고 있는 자동차용 폐윤활유에 있어서는 약 18만톤이 발생된 바 있다. 본 기고에서는 각종 폐유 중 특정폐기물인 폐윤활유를 중심으로한 제목건에 대하여 간략하게 기술하기로 하겠다.

• Tribology and Lubricants
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• 제17권6호
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• pp.447-452
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• 2001

In development process of engine lubrication system, many failure cases are related with aeration problem. Therefore, it is very important to clarify the aeration in the engine oil circuit system. As of today, many factors have been introduced as the major cause in the engine oil aeration. However, still many test data related with those are required to clearly understand it. In this paper the aeration measurement system and calculation method are introduced. And also using this system we measured engine oil aeration for various cases. From these results some conclusions are reduced.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 1998년도 제27회 춘계학술대회
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• pp.3-43
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• 1998

Technical and business transformations are reshaping the business of Diesel engine builders, Diesel lubricant marketers and additive companies. Key issues facing engine builders and end users under these transformations include: -Emission regulations -Vehicle operating costs -Evolving business environments With these challenges come opportunities. For equipment builders and lubricant marketers, these include: -Lubricants meeting global performance requirements -High value lubricant applications -Profitable new businesses

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2004년도 학술대회지
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• pp.249-254
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• 2004

The pressing of car body parts is one of the most important sheet metal drawing processes. The corrosion protection oil applied by the steel mills plays a part in every sheet metal forming operation and also makes up the largest proportion of lubricants used. The idea to combine the corrosion protection properties of a corrosion preventive oil with the lubricity of a drawing oil lead to the development of the Anticorit prelubes. Applied at the finishing lines of the steel mills, they finally serve as lubricant in the press shops. A prerequisite for the suitability of a prelube-type oil is the absolute compatibility with all single processes from the coil to the Body in White. The use of prelubes in steel mills reduces the number and quantity of spot lubricants for additional press shop oiling dramatically. But their true benefits can only be fully achieved if the compatibility principle is applied throughout the manufacturing chain. Therefore, modem prelubes systems are modular, even different viscosities can be part of the same concept. This results in a far-reaching multifunctionality of the Anticorit prelube system for all applications.

• Journal of Mechanical Science and Technology
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• 제17권9호
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• pp.1276-1286
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• 2003

The performance of porous bearing under different lubricants and lubricating conditions was experimentally investigated in this study. In order to carry out the experiments, a new test rig was designed to determine the tribological properties of based sintered bronze journal bearings that were manufactured by powder metallurgy (P/M) techniques. To determine the effects of lubricating conditions with and without oil supplement (OS) on the tribological characteristics of these bearings under static loading and periodic loadings, some experiments were carried out using different lubricants. In the tests, pure base oil (SAE 20W50), two fully formulated commercial engine oils (SAE20W50) and lubricating oils with commercial additive concentration ratio of 3％ were used. The worn surfaces of test bearings were examined using optical microscopy. Experimental results showed that the change in friction coefficient was more stable and in smaller magnitude under static loading than that of periodic loading. In addition, the friction coefficient and the wear rate conducted with base oil resulted in higher values than those of fully formulated oils with and without OS lubricating conditions. The experimental results obtained in this study indicated that the correct selection of lubricant and suitable running conditions were very important on the tribological characteristics of porous bearings.

• Tribology and Lubricants
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• 제19권2호
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• pp.94-101
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• 2003

Used motor oil contains pollutants, including organic chemicals and meta]s. When disposed of improperly - in the trash, on the ground or in a sewer system - the pollutants may reach rivers, lakes or the ground water. Thus, all the waste oil products such as waste motor oil, waste oil container, and waste oil filter should be collected and transported for recycling or disposal by waste oil regulations. Because waste oil container is a valuable resource, waste oil containers can be reused, cleaned, buried, and burned for recycling processes. This paper presents the integrated management system that may increase the efficiency and productivity for collecting and reprocessing waste oil containers such as steel can and plastic container. The integrated management system consists of collection and transportation process management system and confirmation and certification process management system for waste oil containers.

• Tribology and Lubricants
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• 제13권1호
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• pp.70-75
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• 1997

The lubrication characteristics of high-speed ball bearings at oil-starvation have been investigated empirically using the bearings employed in small industrial gas turbine engines. For the close structural simulation, experiments carried our with bearing mounting supports of real engines, such as bearing housings and oil nozzle assemblies with squeeze film dampers. Thus the results of tests can be applied to the design and the development of gas turbine engines. Testing was done by simulating the oil-starvation conditions in engines, such as stopping the oil-supply to the bearing during normal operating, starting without oil-supply at atmospheric temperature, and accelerating with oil-supply at atmospheric temperature. From this study, the relative comparison of the frictional resistance and the resistance due to the bearing cavity oil was demonstrated visually, and the resistance due to the bearing cavity oil was dominant in the resistance of bearing at high speed.

• Tribology and Lubricants
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• 제25권3호
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• pp.157-162
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• 2009

In this paper, the hydrodynamic pressure and minimum oil film thickness of a pin bush bearing for a connecting rod have been analyzed as functions of the number of oil grooves and an arc length of oil grooves. The lubrication characteristic of a pin bush is governed by oil groove design factors, which are considered in this study. The most influential design parameter is a number of oil grooves, which is three oil grooves with an arc length of oil groove, 1/6($60^{\circ}$). This means that oil groove with a long arc length of a pin bush does not contribute to the hydrodynamic pressure development. Thus the optimal design of a pin bush is necessary with an increased number of oil grooves and a reduced arc length.

• Tribology and Lubricants
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• 제13권1호
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• pp.76-81
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• 1997

The lubrication characteristics of high-speed roller bearings at oil-starvation have been investigated empirically using the bearings employed in small industrial gas turbine engines. Testing was done by simulating the oil-starvation conditions in engines, such as stopping the oil-supply to the bearing during normal operating, starting without oil-supply at atmospheric temperature, and accelerating with oil-supply at atmospheric temperature. During testing, the temperature of bearing, the power consumption, and the rotating resistance of the bearing were measured. From this study, on the contrary to the ball bearing, it was found that the resistance of the bearing was higher at the regime of without oil-supply than that at the regime of with oil-supply, despite less power consumption.