• 한국소성가공학회:학술대회논문집
• /
• 한국소성가공학회 2009년도 춘계학술대회 논문집
• /
• pp.168-171
• /
• 2009

High-frequency induction is an efficient way to heat mold surface by electromagnetic induction in a non-contact procedure. Though the induction heating has an advantage in terms of its rapid-heating capacity on the mold surface, it still has a restriction on mold temperature control due to geometric restriction of an induction coil according to the mold shape. It has been recently applied to the injection molding of thin-walled parts or micro/nano structures. For localized induction heating, an injection mold composed of ferromagnetic material and paramagnetic material is used. The electromagnetic induction concentrates on the ferromagnetic material, from which we can selectively heat for the local mold elements. The present study proposed a localized induction heating method by means of selective use of mold material. The feasibility of the proposed heating method is investigated through the comparison of experimental observations according to the mold material.

• Design & Manufacturing
• /
• 제9권1호
• /
• pp.5-8
• /
• 2015

The company Daewoo Precision Industries imported fine blanking press of 40 tons from Switzerland with fine blanking tool in order to produce the fuse part of bomb in 1978 at first in Korea. About 1985 the first fine blanking tool for producing the door lock parts was manufactured in the company Gold Star (now LG). And then this technology was grown up with the growth of automobile industries in Korea. Now 31 companies are closely related to the fine blanking technology and there are total 146 fine blanking presses in Korea. The developments of fine blanking technology in industries have been oriented to the production of precise fine blanking parts, the reduction of die roll height on fine blanking parts, the production of complex fine blanking parts with progressive fine blanking tool including forming and forging technology, the production of high-strength steel fine blanking parts and so on. Some R&D activities in KITECH were introduced.

• 한국표면공학회지
• /
• 제35권3호
• /
• pp.113-120
• /
• 2002

Injection molded plastic parts have many surface defects. These include a weld line, sink mark, flow mark, gloss, shading, scratching etc. Because these surface faults are not aesthetically acceptable, plastic parts are produced through painting or texturing. The purpose of this paper is to develop paintless molded parts using a flow control method. Computer aided injection mold filling simulations were used in order to minimize the number of defects from injection molding. Based on the numerical results, FR(Flame Retardant) HIPS was developed and the guidelines for part design, mold design, and the processing conditions were established. The effects of cost savings, improvements in productivity, and recycling were considered by reducing the number of surface faults and eliminating the painting process.

• 대한기계학회논문집
• /
• 제18권9호
• /
• pp.2396-2403
• /
• 1994

An experimental study on material characterization and mechanical properties of SMC(Sheet Molding Compounds) compression method parts was carried out. Simple compression test using grease oil as a lubricant was carried out to characterize flow stress of SMC at elevated temperatures. Two different mold temperatures, $130^{\circ}C{\;}and{\;}150^{\circ}C$ and two different mold speeds, 15, 45 mm/min were used for preparing the specimen of SMC compression molded parts. Surface roughness, tensile, and 3-point bending tests were used to determine the effects of molding temperatures and speeds on mechanical properties of compression molded SMC parts. Orientation and distribution of glass fiber in the compression molded SMC parts were also investigated by photographing the burnt flat specimen and taking SEM(Scanning Electron Microscope) of cross-sectional T-specimen.

• 대한기계학회논문집
• /
• 제15권6호
• /
• pp.1933-1947
• /
• 1991

본 연구에서는 특징형상기반 CAD 시스템의 기계가공을 고려한 기하학적 모델 링 기능과 부형상의 합성과 해석을 위한 사출성형에 관한 광범위한 지식을 연계, 종합 한 형태의 지식형 CAD 시스템을 제안하였다.

• 한국정밀공학회지
• /
• 제17권9호
• /
• pp.210-221
• /
• 2000

Plastic mold designers and frequently faced with optimizing multi-quality issues in injection molded parts. These issues are usually in conflict with each other and thus tradeoff needs to be made to reach a final compromised solution. in this study an automated injection molding design methodology has been developed to optimize multi-quality characteristics of injection molded parts. The features of the proposed methodology are as follows : first utility theory is applied to transform the original multi-objective problem into single-objective problem. Second is an implementation of a direct search-based injection molding optimization procedure with automated consideration of robustness against process variation. The modified complex method is used as a general optimization tool in this study. The developed methodology was applied to an actual mold design and the results showed that the methodology was useful through the CAE simulation using a commercial injection molding software package. Applied to production this study will be of immense value to companies in reducing the product development time and enhancing the product quality.

• 산업공학
• /
• 제9권1호
• /
• pp.13-24
• /
• 1996

Quality of injection molded parts is dependent on both mold design and processing conditions. From the mold design point of view, an optimal shrinkage should be used to compensate the shrinkage of molded parts. From the processing point of view, it is important to analyze the priority of processing conditions because a number processing conditions affect the quality of molded parts. Processing analysis employing the design of experiment was performed, and the shrinkage of molded part was considered as a characteristic parameter to improve the quality. As the result of the analysis of variance on SN ratio of a characteristic value, injection speed and bolding pressure were selected as two effective process parameters. Regression analysis on shrinkage and processing conditions was carried out, and an optimal processing condition was obtained by the response surface analysis. Shrinkage at the optimal condition could be used to reduce the number of try-cut at the step of mold making. The ranges of indirect control parameter, such as maximum cavity pressure or weight, measured at the optimal processing condition were used for monitoring the quality of molded parts in process.

• 한국전자거래학회지
• /
• 제8권3호
• /
• pp.37-52
• /
• 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.

• 산업공학
• /
• 제12권3호
• /
• pp.480-486
• /
• 1999

Mold base design is one of the most critical steps in production of plastic parts. This paper presents an efficient method for generating a 3D CAD library for injection mold base and mold components. In this paper, a new description language (DL)formats are proposed. These DL formats can represent the geometric feature, the variable dimensions and the assembly structures of mold base and its components. And the processes of adding the mold components and creating the mold assemblies can be performed very easily and efficiently by using DL scripts. Proposed method has been tested by implementation of 3D library with DL scripts and DL-interpreter with C language. The DL and interpreter are independent of CAD system. They were applied to the automatic mold base designing system which works on Unigraphics V15. The system is developed with UG API function under Windows-NT environment.

• 소성∙가공
• /
• 제6권6호
• /
• pp.489-499
• /
• 1997

The injection molding process is analyzed to get the information on the mold design parameters and the optimum process conditions for automotive plastic front fender. The gate position, runner size and cooling channel are determined by the estimation of the flow balance, packing time, uniform cooling and shrinkage and warpage in the injection molding analyses. The procedure can be used in the mold design in the early stage when developing plastic parts.