• Proceedings of the KSME Conference
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• 2003.04a
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• pp.956-961
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• 2003

Recently, environmental pollution has become a significant problem in industry and many researches have been investigated in order to preserve the environment. Environmentally conscious machining and technology have more and more important position in machining process. In the milling process, the cutting fluid has greatly bad influence on the environment. In this study, the machining of blade parts(12Cr steel) using the cutting fluid, compressed cold air and oil mist etc., also, the productivity and the surface topography was improved by using new end-mil tool considering tool material and shape.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.3 no.1
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• pp.22-27
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• 2004

Recently, environmental pollution has become a significant problem in industry and many researchers have investigated in order to preserve the environment. Environmentally conscious machining and technology have more important position in machining process, because cutting fluid has bad influence on the environment in milling process. This research is the experimental study on high speed machining of aluminum alloys through environmentally conscious machining. In this study, the surface roughness and chip appearance was investigated in the machining of aluminum alloys by dry machining, using cutting fluid and oil mist.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2003.10a
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• pp.95-99
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• 2003

Recently, environmental pollution has become a significant problem in industry and many researches have been investigated in order to preserve the environment. Environmentally conscious machining and technology have more and more important position in machining process. The cutting fluid has greatly bad influence on the environment in the milling process. This research is experimental study on high speed machining of aluminum alloys through environmentally conscious machining. In this study, the machinability surface roughness and chip appearance was investigated in the machining of aluminum alloys applied dry machining and using cutting fluid, oil mist.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2004.10a
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• pp.428-432
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• 2004

The important problem in the high speed spindles is to reduce and minimize the thermal effect by the motor and ball bearings. Thermal characteristics according to the bearing preload and hollow shaft cooling are studied for the test spindle with the oil mist lubrication and high frequency motor. Bearings and motor e main heat generation, and heat generation by ball bearings as a function of load, viscosity and gyroscopic moment effect are considered. Temperature distribution and thermal displacement according to the speed of spindle are measured by thermocouple and gap sensor. The results show that the fitting preload and hollow haft cooling are very effective to minimize the thermal effect by the motor and ball bearings.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.15 no.6
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• pp.50-57
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• 2006

The investigation of microscopic precision in high speed endmilling is necessary for machinability evaluation, and the environmentally conscious machining technology have more important position in recent machining process. The microscopic precision of workpiece is influenced by machining environments variation as cutting fluid type and lubricant method. In this study, the cutting forces according to variation of cooling and lubrication are investigated by specially designed tool dynamometer. And the surface roughness, micro hardness and residual stress are evaluated according to machining environment. The characteristics of damaged layer in environmentally conscious machining and conventional machining using cutting fluid are compared experimentally.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.13 no.2
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• pp.127-132
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• 2004

In industrially advanced countries, environmentally conscious machining was eagerly studied because of ecological and economical reasons. As the environmental regulations become stricter, the new machining technologies which take environmental aspects into consideration are being developed. Recently the research institutions have established application method for dry, semi-dry, oil-mist and compressed cold air machining. In this paper the performance of new compressed cold air system for environmentally conscious machining is investigated and machinability of dry and new compressed cold air machining is evaluated. A series of tests are carried out by using measuring equipments in condition of dry and compressed cold air machining.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.21 no.3
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• pp.415-420
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• 2012

Dust collecting performance of axial-vane type cyclone for oil mist was analyzed in this study. For predicting cut diameter size of cyclone, the number and angle of vane (${\beta}_2{^{\prime}}$) was calculated by CFD. As the result, ${\beta}_2{^{\prime}}$ was decreased as the number of vane was increased and the angle of inclination (${\beta}_2{^{\prime}}$) decreased, and it cause strong swirl flow. Therefore, it could be confirmed that as the number of vane was increased and the angle of inclination was decreased, cut diameter size was decreased. Also, by verifying the results of CFD through experiment, the cut diameter size could be 2 ${\mu}m$ at 4 $m^3/min$ of flow rate.

• Particle and aerosol research
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• v.15 no.4
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• pp.139-148
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• 2019

This study was performed for the application of a high-speed centrifugal cyclone to shale gas mining process. This device uses the centrifugal force to control particles similar to typical cyclones, and the disk located inside the cyclone is forced to rotate using a motor. The pressure difference occurred during the rotating of disk. Hence, inflow rate was generated without a blower fan. In addition, flow rate increased with elevating rpm of motor. The installing the disk in multiple stages on the inner rotor increased the instantaneous disk outlet flow. Hence, the control efficiency of oil particle increased from 1.05% to 31.2%. By modifying the structure of the disk so that the air flow to the opposite direction of the cyclone, the control efficiency of oil particles increased to 81.5%. By increasing the capacity of the motor and the size of the disk, the flow rate was increased to 2.5 ㎥/min because the rpm of motor and pressure difference increased. As rpm of motor increased, the cut-off diameter (d_pc) became smaller. Unlike the Lapple's equation, d_pc was inversely proportional to the effective number of rotations (N_e). The control efficiency was maintained even if the concentration of oil particles increased, for this reason, the higher the oil concentration, the more particles were accumulated and controlled.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.15 no.3
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• pp.166-175
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• 2005

Health effects associated with metal working fluid (MWF) exposures include dermatitis, respiratory disease, hypersensitive pneumonitis, and asthma. Frequently, occupational exposures to MWFs are controlled by ventilating an enclosure with an air cleaning unit that includes a fan preceded by various kinds of filtration. There are several kinds of air cleaning units used in machining centers. But the associated troubles have hindered from efficiently using these devices. The main problem is the relatively short period of filter replacement. The reason is that the air cleaning units usually do not have the de-oiling systems, thus leading the earlier clogging of filters and reducing the flow rate of hood. Thus, the first stage of study was conducted to overcome this problem by developing the new oil mist collector equipped with the easy de-oiling system. The principle of de-oiling is that the centrifugal force generated by spinning the drum covered by filter fabric separates oils from the filter fabric. It would be very similar to the spin-dry laundry. By adopting this de-oiling technique, the problems associated with the conventional oil mist collectors could be solved. Several tests/analyses were performed to make the lab-scale oil mist collector. The collection efficiencies and the de-oiling efficiencies of commercially available filter fabrics were tested. Subsequently, the endurance test were conducted by observing SEM photos of filter fabrics and measuring tensile strength/expansion coefficient after spinning the filter drum for 20 minutes at the different rotation speeds. By doing these experiments, the most appropriate filter fabric and rotation speed/duration were selected. Finally, the new oil mist collector was designed. In the near future, this device must be tested in the real machining center.

• Ceramist
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• v.20 no.1
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• pp.103-118
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• 2017

1. 2014년도 우리나라 전체 폐기물 발생량은 146,607천 톤이며, 건설폐기물이 46.2%(67,644천 톤), 사업장 일반폐기물이 38.1%(55,914천 톤), 생활폐기물이 12.4%(18,219천 톤), 사업장 지정페기물이 3.3%(48,810천 톤)을 나타내고 있다. 2. 건설폐기물의 97.9%, 배출시설계 폐기물의 77.3%, 생활폐기물의 67.0%, 지정폐기물의 57.3%가 재활용되고 있다. 3. 2015년도 우리나라 시멘트산업에서 18,801천 톤의 순환자원을 재활용하였다. 폐기물이 6,136천 톤이고, 부산물이 12,665천 톤이다. 부산물은 11,000천톤이 제철슬래그이고, 1,600천 톤이 폐석고(탈황석고 중화석고)로 추정된다. 그리고 폐기물 6,136천 톤은 사업장 일반폐기물의 약 11.0%에 해당된다. 4. 시멘트 톤당 순환자원 사용량(재활용 원단위)은 일본이 400kg/톤 이상이고 우리나라는 300kg/톤 대를 나타내고 있다. 일본이 우리나라보다 재활용량/톤이 많은 이유를 다음에서 찾을 수 있다. (1) 고품위 석회석 원료 (2) 법 제도(지원금 포함) 5. 원료 대체율의 산출은 다음 두 산출방법으로 나타낼수 있다. (1) 이론적인 원료 상한 대체량에 대한 실제 원료 대체량 (2) 이론적인 원료 조합량에 대한 실제 원료 대체량 2015년도 우리날 전체 원료 대체량(17,770천 톤)은 (1)에 의한 대체율 : 71% (2)에 의한 대체율 : 27% 6. 자동차 슈레더 더스트(ASR)를 시멘트산업에서 자원화 하게끔 ASR처리의 보완 및 법적지원(지원금 포함)이 요망된다. 7. 부산물 및 폐기물의 자원화는 시멘트산업에서의 이용이 가장 우수한 장점을 갖추고 있다. 그러므로 시멘트산업에서 폐기물의 자원화를 적극 추진하게끔 제도의 보완 및 시설지원 등 정부의 대책수립이 간절하다.