• Design & Manufacturing
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• 제13권1호
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• pp.61-67
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• 2019

The cooling unit of the industrial showcase consists of a compressor, a condenser and an evaporator. An axial fan is used to circulate the air to improve the efficiency of the heat exchanger. In the past, aluminum fans have been used, which have problems such as low performance, efficiency, high failure rate, and high noise. This study is to develop high performance, high efficiency plastic fan replacing aluminum fan. A major factor in determining the performance and noise of an axial fan is the angle and cross-sectional shape of the blade, which is suitable for raising the lift force, thereby controlling the vortex, which is the main cause of noise and performance degradation. In order to produce a high efficiency injection molded fan, it is necessary to develop a mold that minimizes the deformation of the injection process for the designed shape. In this study, we developed a high efficiency, low noise plastic injection fan with more than 11% performance improvement and noise reduction compared to conventional aluminum fan.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2007년도 춘계학술대회 논문집
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• pp.183-186
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• 2007

The injection molding process has high accuracy and good reproducibility that are essential for mass production at low cost. Conventional molding processes typically use the water-based mold heating and air cooling methods. However, in the nano injection molding processes, this semi-active mold temperature control results in the several defects such as air-flow mark, non-fill, sticking and tearing, etc. Therefore, in order to control temperature of the molds actively and improve the quality of the molded products, the novel nano injection molding system, which uses active heating and cooling method, has been introduced. By using the Peltier devices, the temperature of locally adiabatic molds can be controlled dramatically and the quality of the molded patterns can be improved.

• 한국주조공학회지
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• 제4권4호
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• pp.14-19
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• 1984

In order to clarify the solidification mechanism of Al-Si alloy, Mushy Degree of Eutectic Solidification (MDE) and Centerline Feeding Resistance (CFR) were systematically studied by casting with various compositions of $Al-(6{\sim}18%)$ Si alloys into several kinds of molds having different cooling rates. The results are as follows: 1. CFR% increases slightly as solute concentration increases, but decreases remarkably as the cooling rate of the mold increases, that is, the composition dependence of the alloys has more effect on the change of CFR% than that of the mold cooling rate. 2. The composition dependence of MDE value has the same tendency as that of Degree of Eutectic Solidification (DES). MDE value within the range of hypereutectic composition is larger than that of hypoeutectic and it represents the maximum value at eutectic composition. The higher the cooling rate is, the less the MDE value is.

• 한국전기전자재료학회논문지
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• 제17권3호
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• pp.348-352
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• 2004

The mold transformers have been widely used in underground substations in large building and have some advantages in comparison to oil-transformer, that is low fire risk, excellent environmental compatibility, compact size and high reliability. In addition, the application of mold transformer for outdoor is possible due to development of epoxy resin. The mold transformer generally has cooling duct between low voltage coil and high voltage coil. A mold transformer made by one body molding method has been developed for small size and ow loss, but it needs some cooling method because heat radiation between each winding is difficult. The life of transformer is significantly dependent on the thermal behavior in windings. Many transformer designers have calculated temperature distribution and hot spot point by finite element method(FEM) to analyze winding temperature rise. In this paper, The thermal analysis of pole mount mold transformer with one body molding by duct condition is investigated and the test result of temperature rise is compared with simulation data.

• 한국주조공학회지
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• 제17권3호
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• pp.237-244
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• 1997

This study has been carried out to investigate into the influence of solidification conditions mold on the structure and mechanical properties of Al-5wt%Mg alloy by metallic mold casting. The percentage of equiaxed grain of Al-5wt%Mg alloy castings increased both when pouring temperature decreased and when the low part or bottom of metallic mold was cooled. The hardness was checked and showed that hardness of outside in the castings was higher than that inside, and that it is the highest at the pouring temperature of $680^{\circ}C$. The castings had the highest U.T.S. and elongation when the bottom of metallic mold was cooled. At the same pouring temperature, the structure of castings was changed as the position of cooling parts of metallic mold was varied. When the castings were solidified through cooling of the bottom of the metallic mold, the morphology of Fe intermetallic compound has tendency to change to a Chinese script and the U.T.S. and elongation of Al-5wt.%Mg alloy castings was increased.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 하계학술대회 논문집 Vol.4 No.2
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• pp.1135-1138
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• 2003

The transformer is major equipment in power receiving and substation facilities. Necessary conditions required for the transformer are compactness, lightness, high reliability, economic advantages, and easy maintenance. The pole-mount transformer installed in distribution system is acting direct role in supply of electric power and it is electric power device should drive for long term. Most of modem transformer are oil-filled transformer and accident is happening considerable. The mold transformers have been widely used in underground substations in large building and have some advantages in comparison to oil-transformer, that is low fire risk, excellent environmental compatibility, compact size and high reliability. In addition, the application of mold transformer for outdoor is possible due to development of epoxy resin. The mold transformer generally has cooling duct between low voltage coil and high voltage coil. A mold transformer made by one body molding method has been developed for small size and low loss. One body molding transformer needs some cooling method because heat radiation between each winding is difficult. In this paper, The thermal analysis of pole mount mold transformer with one body molding by duct condition is investigated and the test result of temperature rise is compared with simulation data.

• Design & Manufacturing
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• 제12권2호
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• pp.27-33
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• 2018

Korea's automobile industry, which has grown rapidly to become the world's fifth-largest automobile producer, To cope with environmental pollution and energy problems in order to prevail competitive edge in global market We are investing a lot of research personnel and costs. Among them, for realizing alternative light weight It is a part of the automobile module system that has achieved the technological development before the breakthrough in the injection molding process in the press process. Door module PNL was the subject of research. The door module PNL is expected to cause warpage before the mold production due to the thin and flat product characteristics and fiber orientation characteristic of the material. In this paper, CAE analysis and reverse correction tool Design. CAE analysis to obtain the results of weld line position, bending position and deformation value Through the correction tool, think3, the original product was modified before the mold production to improve the completeness of the parts. In fiber orientation, the position and size of the cooling channel in the mold, the position and size of the gate, Temperature, pressure, time, and work environment. Compared with the result of CAE analysis, the product that was reverse-corrected by Think3 was manufactured, and injection molding was performed. Injection molding products were tested 24 hours later. 3.5 mm to 7.0 mm, and under the fixed condition, the deviation was from 1.1 mm to 1.5 mm. Unlike the CAE analysis, the deviation of the actual injection pressure and the cooling temperature, the fiber orientation of the material, In order to solve this problem, it is necessary to compare the injection conditions with the database, I knew I had to catch the standard.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2004년도 추계학술대회 논문집
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• pp.580-584
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• 2004

In the present study, an evaluation technology for heating channel layout was investigated in SMC molding system design. Conventional design rules of cooling channel in injection molding process were applied to the present work. Finite element thermal analysis with ANSYSTM was performed to evaluate the temperature distribution of mold surface. SMC mold was manufactured to test the effect of a proposed heating channel layout system on the temperature distribution of mold surface and infrared camera was applied to a measurement of temperature. It was shown that infrared camera application was possible in a measurement of temperature distribution on mold surface.

• 소성∙가공
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• 제14권3호
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• pp.263-268
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• 2005

Heating channel layout design and evaluation technology for SMC molding system was investigated in this work. Traditional rules of cooling channel design in injection molding were applied to the present work. Finite element thermal analysis with $ANSYS^{TM}$ was performed to evaluate the temperature distribution of SHC mold surface. SMC mold was manufactured to evaluate the effect of a proposed heating channel layout system on the temperature distribution of SMC mold surface and infrared camera was applied to a measurement of temperature distribution. It was shown that infrared camera application was possible in a measurement of temperature distribution on SHC mold surface.

• Design & Manufacturing
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• 제9권2호
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• pp.10-15
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• 2015

The water has been the suitable for the cooling medium until now. But the water as cooling medium seem to have the limit for high speed injection. The steam plastic molding injection use the steam as the medium when raise the mold temperature. The weld line has been the major quality problems in a plastic injection parts to be difficult to be solved. These problems in injection-molded plastic parts are difficult to find the reason because these issues are usually in tradeoff realtions with each other. The purpose of this paper is to obtain the optimum injection moulding condition for improving the quality of plastic injection parts and to inquire the productivity improvement with the measured cycle time by steam plastic moluding injection. Based on these numerical results, the guidelines of mould design and injection processing condition were established. As a result, the improvement of quality and the reduction of cycle time was achieved.