• Korean Chemical Engineering Research
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• 제44권2호
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• pp.136-148
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• 2006

주물공장에서는 주철을 녹여서 다양한 기계부품을 만든다. 다양한 기계부품을 만들기 위해 목형을 주물사에 넣은 후 주입구를 만들어 녹인 주철을 투입한다. 주물공장은 furan 공정을 포함해 많은 공정으로 이루어지며, 이 중 furan 공정은 목형에 주물사를 부어 넣는 공정이다. Furan 공정의 첫 단계는 주물사가 서로 엉겨 붙어 있게 하기 위해 접착성을 가지는 고분자 물질인 furan류를 주물사에 섞게 되고 녹은 주철이 목형으로 들어가는 것이며 고온에 의해 많은 유해 VOC류가 발생하게 된다. 또 공정조업에서 furan용 모래를 목형이 든 주물형틀에 부어 넣게 되고, 이때도 유독가스와 분진이 발생하게 되며 이 분진은 furan 물질을 포함하고 있어 조업자의 건강에 치명적인 요소가 되며, 이로 인해 조업기피현상이 심화되어 인력수급에 문제가 되고 나아가 사업 경영에 큰 걸림돌이 되고 있다. 본 연구는 이러한 조업기피의 원인을 제거하고 쾌적한 조업환경을 제공하기 위해 유해 VOC류와 집진을 동시에 수행할 수 있는 유해 VOC 및 분진 동시제거 시스템을 최적 설계하고 나아가 현장에 적용 설치하였다. 그 결과 설치 후 포름알데히드의 경우 VOC 0 ppm, 분진 $4{\mu}g/m^3$으로 조업환경이 개선되었으며, 조업자들의 조업 기피 요인을 해소하였다. 또한, 우리는 회사의 고용 문제를 해결하고, 작업의 생산성을 향상시킬 수 있었다.

• 한국정밀공학회지
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• 제29권2호
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• pp.185-192
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• 2012

The paper presents the development of a cooling circuit design system that automatically creates 3D cooling circuit on a given section plane conforming to design specifications, generates 3D solid model of cooling line segments defined on a 2D sketch plane, and verifies interference of 3D cooling channel with the molding die surface. The system was developed mainly for designing plastic injection molding die of vehicular lamp, which helps the mold designer to rapidly construct cooling circuits but also reduce designer's unintended mistakes by conforming to the dimensional design specifications. It is used by an injection molding die manufacturing company in Korea, and reported approximately 20% reduction of cooling channel design time.

• Design & Manufacturing
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• 제2권6호
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• pp.7-10
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• 2008

Injection-stretch blowing system for preform has been developed in this study. The preforms for injection blow molding and injection stretch blow molding are being manufactured by injection molding. However it contains gate mark that affects the bottom crack in the PET bottle. The compression molded preform does not contain gate mark, thus the appearance quality of bottle has been increased and the residual stress near gate(bottom of the bottle) has been reduced. The thickness distributions, haze, and transmittance are well accepted for the preform. Also, flow characteristics of the resin between a core and cavity could be analyzed through computer simulation.

• 소성∙가공
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• 제17권5호
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• pp.337-342
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• 2008

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. In order to actively control temperature of the molds and effectively 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.

• 한국분말재료학회지
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• 제9권4호
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• pp.245-250
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• 2002

In this paper we presented numerical method for the simulation of powder injection molding filling process, which is one of the key processes in powder injection molding. Rheological properties of powder binder mixture such as slip phenomena and yield stress were introduced into the numerical analysis model of powder injection molding filling simulation. Numerical model can be classified into two types. One is 2.5D model which can be introduced to a arbitrary thin geometry and the other is full 3D model which can be applied to a general 3D shape. For 2.5D model we showed the validity of our CAE system with several verification examples. Finally we suggested flow analysis model for 3D powder injection molding filling simulation.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2005년도 춘계학술대회 논문집
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• pp.436-441
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• 2005

In this study, precision injection molding analysis for BGA connector fabrication was performed. A BGA connector model with rectangular micro-holes were introduced to investigate the effect of mirco patterns on the injection molding process. Dual domain(2.5D) mesh and full 3D mesh for BGA connector model were prepared to perform precision injection molding analysis. To verify the Present analysis, experiments of injection molding were performed based on the results of the analysis. It was shown that the type of mesh has a significant effect on the flow pattern of BGA connector

• 동력기계공학회지
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• 제13권4호
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• pp.38-42
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• 2009

The Injection molding is used more than 70% of total production in plastic products. The injection molding process has 4 processes such as filling, packing, cooling and ejecting. now then, cooling process spends the most of times in Injection molding cycle time. Therefore, it is important to control the mold temperature in producing plastic products. The cooling system and time affect the product's quality and productivity. Especially, cooling time has about 60% of total injection cycle time. Therefore, we can improve a productivity by shortening cooling time. In this study, the rapid cooling system was developed and performed a efficiency test. This system could refrigerate coolant to $1^{\circ}C$ and had to need 10 minutes for normal operating.

• 마이크로전자및패키징학회지
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• 제8권3호
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• pp.11-17
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• 2001

The design and manufacture of injection molded polymeric parts with desired properties is a costly process dominated by empiricism, including the repeated modification of actual tooling. This paper presents an expert design evaluation system which can predict the mechanical performance of a molded product and diagnose the design before the actual mold is machined. The knowledge-based system synergistically combines a rule-based expert system with CAE programs. Heuristic knowledge of injection molding is formalized as rules of an expert consultation system. The expert system interprets the analytical results of the process simulation, predicts the performance, evaluates the design and generates recommendations for optimal design alternatives.

• Journal of Biosystems Engineering
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• 제43권2호
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• pp.119-127
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• 2018

Purpose: Fermented feedstuffs have been found to improve productivity, reduce manure odor, and increase immunity. However, because there is not a commercialized pelletizing system for fermented total mixed ration (TMR) for pig feeding in Korea, a pelletizing system using TMR fermented feed was developed. Methods: The particle size, density, and volumetric density of the TMR feeds used in the test were measured. The pellet durability index (PDI, %) value of the pelletized TMR feed based on its moisture content, and the amount of pellet production based on the rotation speed of the compression roller were measured. Results: The test materials, TMR1 and TMR2, were approximately compressed to 387 kg/m3 with 18.2% (w.b.) and 544 kg/m3 with 22.2% (w.b.), respectively. Throughout this pellet molding test, the moisture content from 15 to 20% (w.b.) of mixture feedstuffs, including fermented forage, could be used for pellet molding. Based on the results, a small-scale pellet molding system of fermented TMR was designed and manufactured for pig farms. As rotation speed increased, the throughput increased, whereas the moisture content decreased by approximately 2% (w.b.) because of pellet molding. The best yield of pellets with 94.2% PDI was of 536 kg/h at 135 rpm rotation speed. Conclusions: Although the throughput of the prototype increased as the rotation speed increased, it was difficult to operate because of the greater noise and the lower PDI (%) at the higher rotation speed of the pellet molding rotor. It was found that the best production of pellets using the prototype was 536 kg/h having a PDI of 94.2% or more at a rotation speed of 135 rpm.

• Elastomers and Composites
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• 제47권4호
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• pp.347-354
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• 2012

사출성형에 CAE (Computer Aided Engineering)을 적용함으로써 사출 성형품 설계와 공정조절에 큰 도움이 된다. 또한 성형의 효율성을 최대화하고 개발기간의 단축, 그리고 고품질 제품을 확보하는데 도움이 크다. 특히 신제품 개발에 대한 설계방안을 제시하고 실패율을 감소시킬 수 있다. 현재 사출성형의 CAE는 2D는 물론 3D도 해석이 가능한데 이 두 가지 방식은 약간의 차이를 가짐에도 불구하고 해석 상 차이에 관한 비교 및 일반적인 가이드라인이 정해져 있지 않다. 본 연구에서는 제품의 두께, 형상 그리고 유한요소 수에 따른 2차원 해석과 3차원 해석을 비교하였다. 그리고 실험을 통해 얻은 캐비티 내의 압력과 온도를 해석결과와 비교하였다. 본 연구를 통하여 사출성형의 2D해석과 3D해석에 대한 가이드라인을 제시하고자 하였다.