• Design & Manufacturing
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• 제15권2호
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• pp.30-35
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• 2021

The casting method uses a mold to solidify a liquid metal to make a solid metal. Since it uses a liquid metal with the least deformation resistance, it has the characteristic that it can easily manufacture even a complex shape. However, the process of solidifying a liquid metal into a solid metal inevitably involves a volume change and contains internal defects such as shrinkage holes. Therefore, in the design of the casting plan, an excess volume called a pressurization compensates for the volume shrinkage. in the product, and it induces the shrinkage hole defects to occur in parts other than the product1). In this study, casting analysis was performed using casting analysis software (anycasting) in order to optimize the design of the tilting gravity casting method for automobile brackets. In particular, the filling and solidification analysis according to the shape and volume of the pressurized metal was conducted, and applied to the actual product to study the effect of the pressurized metal on the shrinkage defect. Through this study, it is possible to understand the effect of the pressure metal on shrinkage defects in the actual product and propose a design of the pressure metal that improves reliability and productivity.

• 한국산업융합학회 논문집
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• 제21권1호
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• pp.1-8
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• 2018

The purpose of this study is to develop a high-strength, high-toughness, thin-walled aluminum shock absorber housing product by applying a high vacuum die casting method to improve internal gas defect and formability. The analysis program dedicated for the casting was used because it was too costly and time-consuming to adopt the gating system design. The final casting plan was designed based on the flow pattern of the material filled into the mold and the result of air pressure and air pocket after the material was completely filled in the mold. Gaty shape was designed as a split type. The runner was designed to have the same shape as the initial inlet curve of the cavity, and the flow of the molten metal was prevented from turbulent flow. The most favorable results were obtained when the injection speed was $V_2=4.0m/s$. Defects on pores were reduced by applying high vacuum level inside the mold.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2009년도 춘계학술대회 논문집
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• pp.695-696
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• 2009

• 한국주조공학회지
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• 제14권5호
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• pp.383-392
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• 1994

• 한국주조공학회지
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• 제20권6호
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• pp.400-406
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• 2000

Computer simulation for the predictions of casting defects is very important to produce high quality castings with less cost. Complicate shaped Al solenoid housing part was selected to be cold chamber die cast and a numerical simulation technique was applied for the optimization of the chill vent position and gating. A first design led to insufficient central flow. This flow left the last filled areas falling into the inner portion of the part. And last filled area did not fit the chill vent position. So these resulted in a high possibility of air entrapment in the casting and the design was not proper for the part. The design was improved by using a proper gating system, a more chill vent and proper overflow positions. New design provided a homogenous mold filling pattern and the last filled areas that being located at the overflow and chill vent. Casting plan which produce good quality solenoid housing part was established by using the computer simulation.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2007년도 춘계학술대회 논문집
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• pp.621-622
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• 2007

• 한국산학기술학회논문지
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• 제16권4호
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• pp.2364-2369
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• 2015

본 논문에서는 고정밀 로터용 원심주조기 방식을 연구 및 개발함으로써 관련 업종의 생산성 향상을 위하여 로터의 충진율 해석을 통해 RPM에 따른 로터의 충진율을 비교해 최적의 RPM을 제시하였다. 회전속도가 600 rpm일 때 충진율 99.47%를 보여줌으로써 실제 작업현장에서의 결과와 비슷하므로 이를 토대로 추가적으로 수행하여 그 결과를 이용한다면 보다 정확한 공정설계를 할 수 있을 것으로 사료된다. 또한 소형 레이들의 전도율해석을 통하여 고품질의 주조제품이 생산될 수 있도록 적합한 소형 레이들의 온도를 분석하였다. 니크롬선을 이용한 가열장치가 없는 경우는 $427^{\circ}C$까지 급격히 떨어진 상태로 알루미늄용액이 급격히 굳어지기 시작했다. 그러나 니크롬선의 가열장치가 있는 경우에는 알루미늄 용액의 용융온도인 $660^{\circ}C$이상을 유지한 상태에서 작업을 할 수 있었으며 온도변화가 거의 없음을 알 수 있었다.

• 한국CDE학회논문집
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• 제6권4호
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• pp.263-270
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• 2001

In stamping-die manufacturing, the first step is to build die patterns for lost wax casting process. A recent industry trend is to manufacture the die pattern using 3-axis NC machining. This study identifies technical considerations of the pattern machining caused by the characteristics of Styrofoam material, and proposes technical methods related to establishing a process plan and generating tool paths for optimizing the pattern machining. In this paper, the process plan includes the fellowing three items: 1) deter-mining a global machining sequence-a sequence of profile, top, bottom machining and two set-ups, 2) extracting machining features from a pattern model and merging them, and 3) determining a machining sequence of machining features. To each machining feature, this study determines the machining start point, generates the approach tool path, and proposes a tool path linking method fur reducing the distance of the cutter rapid motion. Finally, a smooth tool path generation and an automatic feedrate adjustment (AFA) method are introduced far raising the machining efficiency.

• 한국환경과학회지
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• 제24권5호
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• pp.699-708
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• 2015

This study was performed to identify the state of the exposure and characteristics of pollutants by each process at 4 casting sites located in Gyeongsang-do from April to November 2013. The concentrations of methanol, crystallized silica glass, formaldehyde and phenol were analyzed by different process - casting process, molding process, core process, and shakeout & finishing process. The highest concentration of methanol was found in casting and molding process, whereas the highest concentration of crystalline quartz(Silica) was observed in core process. The most oxidized steel dusts and the highest concentration of fume were found in shakeout & finishing process. As a result of this study, those labors working at the casting site were found to be constantly exposed to various forms of hazardous chemicals; therefore, it is considered that this is the time to manage and plan how to reduce them. In addition, it is required to thoroughly manage the local exhauster, and improve the process and working environment to reduce various forms of hazardous chemicals.

• 한국콘텐츠학회논문지
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• 제7권12호
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• pp.66-73
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• 2007

주얼리 관련 산업은 국내 시장의 불황, 디자인 개발 부재, 기능 인력의 부재와 높은 인건비 부담으로 고민에 처해 있다. 또한 소비자들의 가격대비 최대한의 가치를 가진 차별화된 제품을 원하고 있다. 주얼리 CAD와 RP 장비는 수작업에 의존했던 주얼리 제조업체에게 생산성을 단축시켜주고 다양한 디자인과 빠른 신제품을 제공해 줄 수 있다. 하지만 아직까지 RP에서 출력된 합성 수지의 직접 주조의 어려움으로 원본 작업에 필요한 만큼의 최상의 주조 소환 사이클을 알지 못하는 상태이다. 이에 본 연구자는 CAD의 활용성과 RP 장비에 관하여 분석하고, 주얼리 CAD 작업과 RP 작업을 통하여 직접 주조가 가능하도록 주조 소환 사이클을 분석하여 원본 제작에 적합한 제품을 제작할 수 있었다. 이 논문을 통해 주얼리 제품의 질적 향상과 차별성을 확보하여 다양하고 경쟁력 있는 디자인과 제품 생산에 새로운 기반을 제공하는 것에 의의를 찾고자 한다.