• 한국CDE학회논문집
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• 제12권1호
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• pp.39-49
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• 2007

Recently three-dimensional (3-D) die design and production process has been widely introduced into the tooling shops of automotive manufacturers to reduce time-to-production of brand-new automobiles. 3-D solid models created in CAD systems are used not only for various simulations for design verification, but also for NC tool path generation to machine dies and their Styrofoam patterns. However, a lot of time and cost will be required to build solid models for dies if designers use only the generalized modeling capabilities of commercial 3-D CAD systems. To solve this problem, it is necessary to customize 3-D CAD system for the specific die design and manufacturing process. This paper describes a dedicated 3-D CAD system based on Unigraphics for die design for automotive body panels. The system provides not only 3-D design capabilities, but also standard part libraries, to enhance design productivity. The design process modeling technology has been introduced to facilitate redesign of the die for the modified panel. By introducing this system, dies can be designed more rapidly in the 3-D space, and their solid data can be directly transferred to CAM tools for NC tool path generation and simulation tools for virtual manufacturing.

• 한국정밀공학회지
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• 제16권6호
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• pp.123-132
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• 1999

This paper describes a research work of developing computer-aided design of lead frame, semiconductor, with blanking operation which is very precise for progressive working. Approach to the system is based on the knowledge-based rules. Knowledge for the system is formulated from pasticity theories, experimental results and the empirical knowledge of field experts. This system has been written in AutoLISP on the AutoCAD using a personal computer and in I-DEAS Drafting Programming Language on the I-DEAS Master Series Drafting with Workstation, HP9000/715(64). Transference of data between AutoCAD and I-DEAS Master Series Drafting is accomplished by DXF(drawing exchange format) and IGES(initial graphics exchange specification) methods. This system is composed of five modules, which are input and shape treatment, production feasibility check, strip-layout, data-conversion and die-layout modules. The process planning and Die design system is designed by considering several factors, such as complexities of blank geometry, punch profiles, and the availability of a press equipment and standard parts. This system provides its efficiecy for strip-layout, and die design for lead frame, semiconductor.

• 한국정밀공학회지
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• 제13권8호
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• pp.146-154
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• 1996

In this work, rapid prototyping and three-dimensional finite element analysis are simultaneously applied to the die design of metal forming processes. Rapid prototyping is a new prototyping technology which produces three-dimensional part models directly from CAD data and has been extensively applied to various manufacturing processes. There are many types of rapid prototyping systems due to their building principles and materials. In this work, Stereolithography Apparatus(SLA), which is the most widely used rapidprototyping system, is introduced to manufacture the die set. For general preparation of STL file, which is the standard input file of rapid prototyping system, mesh data which are used in describing the die surface in finite element analysis are translated so that rapid prototyping and finite element analysis are dffectively connected. A die set for spider forging and a clover punch for deep drawing section are manufactured effciently using SLA prototypes, and metal forming experiments are carried out using them. Comparing the result of experiments with that of analyses, the processes can be predicted and designed successfully.

• 한국정밀공학회지
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• 제19권1호
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• pp.107-118
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• 2002

This paper deals with an automated computer-aided process planning and die design system by which designer can determine operation sequences even if they have a little experience in process planning and die design of quasi-axisymmetric cold forging product by cold former working. The approach to the system is based on knowledge-based rules and a process knowledge base consisting of design rules is built. Knowledge for the system is formulated from plasticity theories, empirical results and the empirical knowledge of field experts. Programs for the system have been written in AutoLISP for the AutoCAD using a personal computer. An attempt is made to link programs incorporating a number of expert design rules with the process variables obtained by commercial FEM softwares, DEFORM and ANSYS, to form a useful package. The system is composed of three main modules and five sub-modules. The process planning and die design module considers several factors, such as the complexities of preform geometry, punch and die profiles, specifications of available cold farmer, and the availability of standard parts. As the system using 2D geometry recognition is integrated with the technology of process planning, die design, and CAE analysis, the standardization of die parts for wheel bolt requiring cold forging process is possible. The developed system makes it possible to design and manufacture quasi-axisymmetric cold forging product more efficiently.

• 한국정밀공학회지
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• 제20권4호
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• pp.29-38
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• 2003

This paper deals with an automated computer-aided process planning and die design system with which designer can determine operation sequences even after only a little experience in process planning and die design of multi former-bolt products by multi-stage former working. The approach is based on knowledge-based rules, and a process knowledge base consisting of design rules is built. Knowledge fur the system is formulated from plasticity theories, empirical results and the empirical knowledge of field experts. Programs for the system have been written in AutoLISP for AutoCAD with a personal computer. An attempt is made to link programs incorporating a number of expert design rules with the process variables obtained by commercial FEM softwares, DEFORM and ANSYS, to form a useful package. The system is composed of four main modules. The process planning and die design module considers several factors, such as the complexities of preform geometry, punch and die profiles, specifications of available multi former, and the availability of standard parts. It can provide a flexible process based on either the reduction in the number of forming sequences by combining the possible two processes in sequence, or the reduction of deviation of the distribution and the level of the required forming loads by controlling the forming ratios. The system uses 2D geometry recognition and is integrated with the technology of process planning, die design, and CAE analysis. The standardization of die parts for multi former-bolt products requiring a cold forging process is described. The system developed makes it possible to design and manufacture multi former-bolt products more efficiently.

• 한국전자거래학회지
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• 제8권3호
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• pp.37-52
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• 2003

PLIB으로 알려진 ISO 13584 부품 라이브러리 국제 표준은 상품의 분류와 각 상품 분류별 특성을 묘사하는 기준으로서 전자 상거래 분야로 그 응용영 역을 넓혀 나가고 있다. PLIB 표준은 여러 권으로 구성된 표준인데, 그 중 파트 42는 전자 카탈로그 또는 부품 라이브러리의 데이터 사전 (Data Dictionary)를 작성하는데 정보모델 (Information Model)과 설계원칙 (Design Principles)을 제공한다. PLIB 파트42의 정보모델을 기반으로 작성된 데이터 사전을 이용하여 전자 카탈로그 시스템을 구축하면, 향후 산업별, 부품대상별로 구축될 다양한 전자 카탈로그 시스템간의 통합 (Integration)과 상호운용 (Interoperation)을 쉽게 달성할 수 있다. 본 연구는 우선, 전자 카탈로그 또는 부품 라이브러리에서 데이터 사전의 역할과 요구 사항을 정리하고, PLIB 파트 42의 내용을 분석한다. 그리고 분석 결과를 바탕으로 금형부품 데이터 사전을 작성하고 이를 이용하여 기업간 전자 상거래 (B2B e-Commerce)용 전자 카탈로그 시스템을 구축한 결과를 정리한다.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2003년도 춘계학술대회논문집
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• pp.44-48
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• 2003

In metal working, cold forging that has profit to satisfy dimension accuracy is using in various manufacturing products. Recently, most of the interest thing is precision forging of gear, Gear forging product is more strength than broaching gear, and it has many advantages with reduction of factory expenses. The reason of difficulty to improve accuracy of gear dimension compare to another products is the dimension accuracy is very high, approximately 10$\mu\textrm{m}$, and because die of involute teeth and elastic strain of forged tool differ from standard curve. This paper represent quantitative analysis of die and teeth of forged tool, namely difference of curves, with experiments and analyze the factor of dimension gap, finally, will design compensated involute curve.

• 대한화학회지
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• 제11권4호
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• pp.165-169
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• 1967

X-線 螢光分析에 依한 微量金屬 Hg, Cu, Pb, Zn, Ni, Co와 Fe의 定量을 하기 爲하여 測定 試料의 調製에 關한 새로운 方法을 發展시켰다. 微量金屬들을 水溶液으로부터 pH 8에서 $Al_2(SO_4)_3$를 Carrier로 $H_2S$을 通하여 沈澱시켰다. 이 金屬硫化物 沈澱을 Membranfilter로 濾過한 後 Gelatine으로 沈澱을 固定시켰다. 이것을 X-線 螢光分析에 依하여 各 金屬들의 絶對量을 分析한 結果 다른 方法으로 調製한 試料보다 그 層이 얇은므로써 Matrix 영향이 나타나지 않았다. 또 $Al_2(SO_4)_3$를 Carrier로 使用하므로 좋은 再現性을 얻었다. 그리고 위 方法으로 調製한 試料에서 Hg, Cu, Pb, Zn, Ni와 Co는 濃度範圍 50~1000p.p.b에서 相對 標準偏差 5.0%로 測定되었고 Fe는 濃度範圍 50~1000 p.p.b에서 相對 標準偏差 6.1%의 좋은 結果를 얻었다.

• 한국산학기술학회논문지
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• 제5권4호
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• pp.309-314
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• 2004

네일 파일(nail file)을 제조할 때 재료는 강판(두께 0.5㎜)을 사용하고 가공방법은 외형형상을 만들고 Φ 0.8-Φ 1.0㎜의 구멍을 약 300여개 뚫어 완성한다. 이들의 가공방법은 에칭(etching)에 의존하여 제조원가의 33%를 에칭비가 차지하고 있으므로 제조원가의 상승원인이 되고 에칭시 부식제(etching reagent)의 잔류도 환경 친화적이 못되며 재료가 강판이기 때문에 제품에 녹(rust)이 생기므로 이들의 문제점을 해결하고자 다음과 같이 연구개발을 수행하였다. 제품의 녹 방지를 할수 있는 적합한 재질 선택 방법을 고찰하고, 에칭 가공방법을 사용하지 않고 금형을 이용한 프레스 가공으로 교체하기 위하여 프레스 스탬핑시의 스트립 레이아웃(strip layout)기법을 연구개발하고, 금형 부품 중에서 작업 중 절손이 빈번한 보통의 표준펀치를 퀼형의 펀치로 개발 하므로써 프로그레시브 퍼퍼레이팅 금형(progressive perforating die)을 개발하게 되었다.

• 신재생에너지
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• 제18권3호
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• pp.23-31
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• 2022

This study evaluated the potential of coffee waste (CW) and used frying oil (UFO) as an additive in the production of pitch pine (PIP) and Mongolian oak (MOK) pellets. Ash contents obtained from CW and UFO were 0.5% and <0.1%, respectively. The calorific values of UFO (31.4 MJ/kg) and CW (26.3 MJ/kg) are higher than PIP (20.6 MJ/kg) and MOK (19.1 MJ/kg). For pellets fabricated using a pilot-scale flat-die pellet mill, regardless of fabricating conditions, moisture content (MC) and bulk density of PIP and MOK pellets satisfied the A1 wood pellet standard for residential and small-scale commercial uses, as designated by the National Institute of Forest Science (NIFOS) of the Republic of Korea. When CW was used as an additive, durability of PIP pellets made with 12%-MC sawdust and MOK pellets increased. The optimal conditions for producing PIP and MOK pellets could be by adding 20 mesh CW as an additive and the using of 12%-MC sawdust. However, durability of PIP pellets and ash content MOK pellets did not satisfy the A1 wood pellet standard of NIFOS. Thus, further research is needed to improve the properties of wood pellets with additives.