• 한국농공학회지
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• 제36권1호
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• pp.141-152
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• 1994

Our experiment investigated the degree of soil contaimination caused by oil leakage. Each soil sample was taken by boring 5, 8m below the test areas, located 5 to 30m from storage tanks at oil stations. According to the results from a series of laboratory tests(both soxhiet extract test and gas chromatograph test), Traces of a light oil were found in all samples except in Dj8, rocky soil and gasoline and petroleum were not detected. We concluded that soil contamination was caused by the corrosion of storage tanks or alternatively by oil overflow caused during the flooding of underground water seeping into the tank during heavy rain fall or the spillage caused by carelessness during lubrication. Old stations without a concrete box enclosing their metal tanks run a greater risk of oil leakage. To research the effect of oil leakage on plant growth and underground water, We examined the results of research conducted overseas. According to these results, when oil leakage occurs, plant growth is repressed and agricultural crops experience low productivity levels. Also, the contamination of underground water can be serious when oil spreads to the aquifer layer. As a result of these problems, to prevent oil leakage and minimize its contaminating effects at oil stations, it is necessary to improve facilities of storage tanks and have the monitoring system of oil leakage.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2006년도 춘계학술논문 발표대회 제6권1호
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• pp.177-180
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• 2006

The accidents of oil leakage is increasing in the Underground Concrete structures for Oil Storege. In the result, the waterproofing in the underground structures is melt down and cannot fulfil its Performance. This study shows an experimental study in the effects of the oil leakage to on the performance of Waterproofing Materials. In order to investigate the actual condition and the problems, a comparative analyses were conducted considering the various types of leakage. Utilizing the obtained results at the basic data for test methods and the standard of quality, we intended to propose a strategy to develop an innovated waterproofing Materials and improve the clean environment of underground structures.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2001년도 제34회 추계학술대회 개최
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• pp.186-193
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• 2001

In the high pressure state, the leakage flow rate of hydraulics is one of serious problems and the great reason to decrease the volume efficiency. In this paper, I tried to clarify tribology characteristics for the slipper hydrostatic bearing in swash plate type axial piston pumps and motors by means of experiment . I measured the leakage flow rate between swash plate and piston shoe with change the supply pressure and oil temperature at a swash plate angle of 0。 . And I also investigated the slipper pocket pressure and calculated oil film thickness for theoretical method. So. 1 have analyzed the tribology characteristics of hydrostatic bearing for leakage flow rate and oil film thickness with oil temperature and supply pressure.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 C
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• pp.1966-1968
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• 2000

Globally, oil-filled paper-insulated cables and cross-linked polyethylene-insulated cables have been mainly applied for a underground power transmission line. The oil-filled cable has the hydraulic system in which insulating oil, expanded and contracted by temperature changes, is absorbed and supplied. This system enable us to detect oil leakages from the cable. But it has some problems such as difficulty in detecting minor leakages and a relatively long period of fault detecting. And so, this paper introduce a new leakage detection system, improved from the current one.

• Tribology and Lubricants
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• 제24권4호
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• pp.179-185
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• 2008

Microporous polymer lubricants(MPLs) are solid polymer materials containing micropores which are filled with liquid lubricants, and which are molded or formed to suit rolling bearings or other machine parts requiring lubrication. MPLs can be effectively applied to provide long-term, maintenance-free lubrication of a variety of machine elements without fully replacing of oils and greases. The application of rolling bearings packed fully with an MPL could reduce or eliminate the problems such as grease deterioration, leakage, under-lubrication caused by insertion of water or foreign matters under severe operation conditions. This paper discuss the application of MPLs for lubrication of rolling ball bearings. Two different MPLs were synthesized and the features of MPLs were tested. Characteristics of the bearings which are packed fully with synthesized MPLs were investigated using SEM, TG/DSC, extents of oil leakage, OIT, and life time test. After these preliminary tests twelve MPLs were synthesized and evaluated by measuring extents of oil leakage and OIT values. Then synthesis conditions for the optimum MPL were selected by SSRED(Six Sigma Robust Engineering Design) pro gram using extents of oil leakage and OIT values respectively. The optimum MPL by means of OIT value showed higher performance such as long life time and application at higher temperature of $140^{\circ}C$ than previous temperature of $100^{\circ}C$.

• 한국산학기술학회논문지
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• 제21권3호
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• pp.321-327
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• 2020

최근 2년간 군 기동화력장비의 엔진 생산 공정 중에 발생한 주요 품질문제 중에는 엔진오일 누유가 가장 많은 비중을 차지하고 있다. 이를 최소화하기 위해서는 엔진오일 누유에 대한 근본적인 원인 파악과 다빈도로 발생되는 누유 부위에 대한 파악이 필요할 뿐만 아니라 더 나아가 품질비용 감소를 위해서는 엔진 조립 및 검사공정에서 누유에 대한 사전식별이 필요하다. 본 연구에서는 형광염료가 주입된 엔진오일을 통하여 누유를 가시화하고 엔진오일 누유 현상에 대한 식별성을 증대시켜 군 기동화력장비 엔진의 생산품질을 향상시키고자 하였다. 이를 위하여 기존에 사용하는 엔진오일과 형광염료가 주입된 엔진오일의 특성분석을 통하여 대체 가능성에 대해 검토하였으며 엔진오일 주입 공정과 누유검사 공정을 개선하여 엔진오일 누유에 의하여 발생할 수 있는 정비기간 및 시간을 최소화 시키고자 하였다. 최종적으로 본 연구결과를 토대로 군 기동화력장비 엔진의 신뢰도 확보 및 엔진 생산업체의 품질관리 능력 향상을 통하여 엔진 생산 공정간 발생할 수 있는 품질비용을 최소화 시킬 수 있다고 사료된다.

• 센서학회지
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• 제23권4호
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• pp.266-271
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• 2014

Chemical sensors are used in various industrial facilities such high-risk and prevent the leakage of substances, important in life and environmental protection and the safe use of industry, used for management. In particular, high-temperature environments such as power generation equipment of the rotating part due to leakage generated by the various oil, power plants Shut Down, fire, work environment (exposure to various chemical solution and gas leak) and various water, air and soil pollution causes. Thus, over the long term through various channels such as crops and groundwater contamination caused by the slow, serious adverse effect on the ecosystem. In this paper, synthetic lube oil and high pressure hydraulic fluid leakage and immediately detect a new Printed Electronic implementation of technology-based film-type sensors, and its performance test. Thus, industrial accidents and environmental pollution and for early detection of problems, large accidents can be prevented. Experimental results of the synthetic lube oil and high pressure hydraulic fluid solution after the contact time depending on the experiment and the oil solution of the sensor material of the conductive porous PE resistance value by a chemical reaction could be confirmed that rapid increase. Also implemented in the film-type oil sensor electrical resistance change over time of the reaction rate and the synthetic lube oil is about 2 minutes or less, the high pressure hydraulic fluid is less than about 1 minute was. Therefore, more high-pressure hydraulic fluid such as a low volatility synthetic lube oils are the resistance change and the reaction rate was confirmed to be the slowest.

• 한국정밀공학회지
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• 제16권3호통권96호
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• pp.30-37
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• 1999

This paper represents the development of the brake system for the inline skate using bellows. The inline skate that is used at present has defects due to frequent impulse, which weakens the breaking force by damaging the parts. Therefore to solve these problems a break system for the inline skates using hydraulics is suggested. To solve the oil leakage problems, bellows is used. Also to prevent the breaks from not touching the ground when skating the bellows is placed at the heel, high as possible. To obtain fast response speed, the ratio of inner diameter of the bellows is changed so that with only a small displacement from the bellows the rubber pad attached to the bellows will touch the ground fast. The performance of the break system using bellows depends on the optimal design of the bellows. Therefore the parameters that changes the form of the bellows are tested and also the interaction between the forces are investigated. The performance of new model brake system with bellows and old model system with only a rubber pad without bellows was estimated through observation of braking posture.

• Tribology and Lubricants
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• 제16권3호
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• pp.157-165
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• 2000

A discharge free Electro-Rheological Squeeze Film Damper (ER-SFD) with predetermined-clearances at leakage ends can inherently eliminate electric discharge problems while still supplying stable leakage control. Test results show that the damping force of the slotted-ring ER-SFD is mainly affected by electric voltage, oil supply pressure, position of the damper and ratio of effective surface area of slotted-rings. As the supply voltage is larger, the amplitudes of both slotted ER-SFD and rotor are decreased at first and second critical speeds. The influence of the oil supply pressure and the effective surface area ratio was shown mainly near the first critical speed. The effective surface area ratio of slotted-rings influences the reduction of flexible rotor vibration. As a result, experimental results confirm that the slotted-ring ER-SFD satisfactorily controls the flexible rotor vibration, while eliminates the inherent electric discharge problems in conventional ER-SFDs.

• 한국해양공학회지
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• 제23권3호
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• pp.30-34
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• 2009

Oil hydraulic piston pumps are being extensively used in the world, because of simple design, light weight and effective cost etc. An oil hydraulic pump is likely to have serious problems of high leakage, friction and low energy efficiency according to large time use. In the oil hydraulic piston pumps the clearance between the valve block and piston plays an important role for volumetric and overall efficiency. In this paper, the wear property of the SACM645 material used the hydraulic piston pump has been work out by experimentation with variable heat treatment. To investigate the effect according to the piston surface condition, seven different types specimen were prepared. From the wear test results, induction hardening and nitration were definitely superior to the others. On the whole, nitration was estimated for high strength material to wear resistance.