• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.05a
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• pp.1008-1011
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• 2002

In industrially advanced countries, environmentally conscious machining was eagerly studied because of ecological and economical reasons. As the environmental regulations become stricter, new machining technologies which takes environmental aspects into consideration are being developed. Industry and research institutions established applications for dry, semi-dry, oil-mist and compressed cold air machining. This paper investigates the performance of new compressed cold air system for environmentally conscious machining and evaluates machinability of dry and new compressed cold air machining. A series of tests are carried out using measuring equipments under dry and compressed cold air machining.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.10 no.3
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• pp.87-93
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• 2011

CNC lathe machining has been widely used for parts machining of vehicles, aircraft, ships, electronics, etc. because cost savings for shortening processing time and increasing productivity are great. In this study, the purpose is to investigate the effect of cooling methods such as oil mist, water-soluble cutting oils on the workpiece surface roughness with the cutting speed, cutting depth, tool nose radius and feed rate of CNC lathe machine as a parameter in the cutting process of the aluminum alloy 2024 which is used a lot recently on aircraft parts. It is found that oil mist is coolant and water-soluble cooled by cutting the experimental conditions, cutting speed and cutting depth without effecting the surface roughness value was constant.

• Proceedings of the KSME Conference
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• 2003.04a
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• pp.962-967
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• 2003

Recently, environmental pollution has become a serious problem in industry, and many researches have been done in order to preserve the environment. The coolant, which promotes lubrication, cooling and penetration, contains chlorine, sulfur and phosphorus to improve the machining efficiency. These additives, which move around into the air during machining, pollute working. Therefore, many researches on how to reduce the amount of coolant during machining have been carried out. However, to reduce even small amount of coolant causes high temperature of a workpiece and it brings thermal defects. In this study, the experiments of wet & dry grinding using cooling methods (using coolant only, mist and compressed cold air only) are performed to solve the problem of environmental contamination and to get a better surface integrity of a workpiece by comparing surface roughness, roundness and residual stress.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.20 no.1
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• pp.13-16
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• 2011

It is a tendency where the number of the restaurant is increasing recently with advancement of the food service industry. In comparison, Noxiousness fine MIST and the removal are passively done in about offensive odor which occurs meat products processing as emitting like that in the atmosphere. Because adherence lamination in the exhaustion line pipe has need of a periodic cleaning and change, it must discontinue the business of long time. In this paper, The technique development on fine MIST, dust of offensive odor and filtering which occur meat products processing prevents adherence/lamination of fine MIST in exhaustion line pipe. And the source prevents the environmental matter which is emitted in the atmosphere under maximizing boil offensive odor and the filtering effect of noxiousness MIST.

• Journal of environmental and Sanitary engineering
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• v.13 no.3
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• pp.121-127
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• 1998

This study investigated exposures to oil mist obtained from an cutting oil manufacture shop and 5 machining shops and also analysis of some oils. The results were that geometric average concentrations of oil mist were $0.29 mg/m^3$, which was less than current $TLV(5mg/m^3$) in Korea. The proper case of either type of system will ensure that atmospheric concentrations of oil mist in machine shops will be within the TLV. It should be remembered, however, that this TLV was established before there was any suggestion that in the inhalable of oil mist might rarely be carcinogenic, and so it seems prudent to keep atmospheric content as low as possible. The analysis of insoluble cutting oils with GC-MSD showed that considerable suspected PAHs were contained. But soluble cutting oil(KSM-W2) didn't almost contain PAHs.

• Ceramist
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• v.9 no.6
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• pp.18-23
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• 2006

In this article, the present activities regarding research and development of continuous SiC fiber reinforced ceramic matrix composites (CFCC) in Japan are reviewed. The key technologies in SiC fiber composites are interphase between fiber and matrix and its oxidation resistance. To improve oxidation resistance of interphase, various kinds of technologies such as environment barrier coating, high dense matrix, unti-oxidation matrix, multi-layered intephase have been developed. It is suggested that high performance, affordable processing cost, and excellent reliability will be important factors to be in practical use of CMCs in future.

• Applied Chemistry for Engineering
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• v.29 no.2
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• pp.229-236
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• 2018

A customized cleaning agent was investigated for improving the performance decreased by the pollution of collecting plates in an electric fume collector (EFC) which was developed and applied for the purification of effluent gas including oil mist from the textile industry. The pollutants on the surface of collecting plates were blackened by the condensation of oil mist for a long time and difficult to remove by general cleaning agents. The composition of an optimized cleaning agent consisted of alkali, alcohol, glycol and non-ionic surfactant sources was determined by considering the pollutant properties and effect on the damage of the basic metal of collecting plate and so on. The developed cleaning agent solution diluted by 9.1% was applied to the field test, and also the pollutants strongly adhered on collecting plate surfaces were successfully removed by a simple spraying method. The effluent gas purification efficiency of EFC increased significantly by cleaning of collecting plates.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.9 s.180
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• pp.2159-2166
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• 2000

Recently, high performance machining center requires special type of sealing mechanism that prevent a leakage of oil jet or oil mist lubrication system. Sealing of oil-air mixture plays important r oles to have an enhanced lubrication for performance machining center. Current work emphasizes on investigations of the air jet effect on the protective collar type labyrinth seal. To improve sealing capabilities of conventional labyrinth seals, air jet is injected against the leakage flow. In this study, an adapted model is introduced to improve sealing capability of conventional non-contact type seals. It has a combined geometry of a protective collar type and an air jet type. Both of a numerical analysis by CFD (Computational Fluid Dynamics) and experimental measurements are carried out to verify sealing improvement. The sealing effects of the leakage clearance and the air jet magnitude aic studied in various parameters. Gas or liquid has been used as a working fluid for most of nori-contact types seals including the labyrinth seal. However, it is more reasonable to regard two-phase flows because oil mist or oil jet are used for high performance spindle's lubrication. In this study, working fluid is regarded as two phases that are mixed flow of oil and air phase. Both of turbulence and compressible flow model are also introduced in a CFD analysis to represent an isentropic process. Estimation of non-leaking property is determined by amount of pressure drop in the leakage path. Results of pressure drop in the experiment match reasonably to those of the simulation by introducing a flow coefficient. Effect of the sealing improvement is explained as decreasing of leakage clearance by air jetting. Thus, sealing effect is improved by amount of air jetting even though clearance becomes larger

• Transactions of the Korean Society of Automotive Engineers
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• v.24 no.5
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• pp.549-555
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• 2016

This research was performed to determine the oil separation characteristics of the specially designed oil filter installed in a PCV cylinder head passage. The oil filter was specially designed with fleece for separating oil mist from blow-by gas. The fleece, made of fiber fabric material, is placed in the oil filter case to absorb oil mist with a small pressure drop during blow-by gas through the filter. To do this, 3-D CFD analysis was simulated for the simplified PCV system with the oil filter using the commercial code, Ansys CFX. Results showed that the oil filter's efficiency with fleece sharply increased as oil droplet size increased.

• Ceramist
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• v.22 no.3
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• pp.301-315
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• 2019

We prepared hybrids between layered double hydroxide (LDH) and natural plant extract such as Peaonia suffruticosa Andrews (PS) and Peaonia Japonica (PJ) which was confirmed anti-bacterial activity through paper disc diffusion assay. According to X-ray diffractometer, scanning electron microscope, zeta-potential measurement and quantification of extract loading amount in hybrids, we confirmed that similar amount of PS and PJ loaded on inter-particle pore of LDH with partial adsorption on surface of LDH through reconstruction process. We also evaluated the bacterial colony forming inhibition of PS extract, PJ extract, PS-LDH and PJ-LDH hybrids against Escherichia coli as gram negative bacterium and Bacillus subtilis as gram positive bacterium, suggesting that both hybrids have enhanced anti-bacterial activity compared with extract itself.