원형포밍 성형 시 크랙 발생 최소화 방안에 관한 연구

손종민,김세환,이춘규,Son, Jong-Min,Kim, Sei-Whan,Lee, Chun-Kyu 한국금형공학회 2016 한국금형공학회지 Vol.10 No.3

Foaming is a step of forming by the ratio of the internal combustion chamber in a state where the in flow of the material is suppressed, if the diameter is small and a high to a crack generated on the molding is not possible. The present study, we studied using as part experiments for forming the circular shape of the forming height of 10 mm without the occurrence of cracks, results preformed primary, the need to set the height of the forming than the height of the product, preformed secondary. It was able to increase the height of the molded product with less than the height of the next step to be carried out compression processing to create a small comer of the desired shape. In addition, it was found that on a great influence on the quality of the final quality on the final molding of the primary preformed, secondary.

프레스 금형을 이용한 석재판 고정장치 개발

백승엽,김선용,Baek, Seung-Yub,Kim, Sun-Young 한국금형공학회 2008 한국금형공학회지 Vol.2 No.4

The productive products are required diversification of product development and advanced for competitiveness. A lot of methods to fix architecture wrapping panels and stone materials are developed in domestic area very much. In this paper, it is very important that a fixing device of slate and molds were developed to reduce the production cost and improve safety. Therefore new model was suggested to reduce manufacturing cost and structure design and FEM analysis were performed to manufacture die press dies for mass production.

Metal Powder에 따른 증기화 증폭 시트의 개발을 통한 열 중량 분석 및 고출력 전자빔의 가공 특성 분석

김현정,정성택,이주형,백승엽,Kim, Hyun-Jeong,Jung, Sung-Taek,Lee, Joo-Hyung,Baek, Seung-Yub 한국금형공학회 2020 한국금형공학회지 Vol.14 No.1

An electron beam was used to mainly utilize for polishing, finishing, welding, a lithography process, etc. Due to the high technical level of difficulty of high-power density electron beam, it is difficult to secure related technologies. In this study, research was carried out to improve the machinability by developing the vaporized amplification sheets to realize the electron beam drilling technology. Their vaporized amplification sheets were analyzed by using the measurement of chemical and composition, which is such as TGA, SEM. We analyzed micro-hole processing using a microscope. Also, the thermal characteristics of vaporized amplification sheets are highly significant for applying to high-power density electron beam technique. So, we finished the vaporized amplification sheets according to the process conditions and analyzed it according to the machining conditions of the electron beam. It was confirmed that the effect on the experimental results differs depending on the influence of the metal powder contained in the developed material.

인공신경망 구조에 따른 사출 성형폼 품질의 예측성능 차이에 대한 비교 연구

양동철,이준한,김종선,Yang, Dong-Cheol,Lee, Jun-Han,Kim, Jong-Sun 한국금형공학회 2021 한국금형공학회지 Vol.15 No.1

The quality of products produced by injection molding process is greatly influenced by the process variables set on the injection molding machine during manufacturing. It is very difficult to predict the quality of injection molded product considering the stochastic nature of manufacturing process, because the process variables complexly affect the quality of the injection molded product. In the present study we predicted the quality of injection molded product using Artificial Neural Network (ANN) method specifically from Multiple Input Single Output (MISO) and Multiple Input Multiple Output (MIMO) perspectives. In order to train the ANN model a systematic plan was prepared based on a combination of orthogonal sampling and random sampling methods to represent various and robust patterns with small number of experiments. According to the plan the injection molding experiments were conducted to generate data that was separated into training, validation and test data groups to optimize the parameters of the ANN model and evaluate predicting performance of 4 structures (MISO1-2, MIMO1-2). Based on the predicting performance test, it was confirmed that as the number of output variables were decreased, the predicting performance was improved. The results indicated that it is effective to use single output model when we need to predict the quality of injection molded product with high accuracy.

요인분석법을 이용한 파인 블랭킹 공정의 파단면 최소화에 관한 연구

이범순,김옥환,Lee, Beom-Soon,Kim, Ok-Hwan 한국금형공학회 2021 한국금형공학회지 Vol.15 No.1

The Fine Blanking process is an effective precision shearing process that can obtain a smooth cutting surface and high product precision through a single blanking process. It is widely used in various manufacturing fields. However, shearing through this fine blanking process is only intended to minimize burrs, die rolls and fracture surfaces and does not completely remove them. Therefore, it is necessary to study the minimization of burrs, die rolls and fracture surfaces in the fine blanking process. In this study, a study was conducted on the relationship between the fracture surface and process conditions that occurred during product production using the fine blanking process. For this purpose, the shape of the V-ring indenter, the distance to the punch, and the pressure force, clearance, shear rate, and physical properties of the material were selected as process and design variables, and the relationship with the fracture surface according to each process and design condition was tested. It was analyzed through the Experimental Design Method.

근적외선 램프를 적용한 에너지 절감형 압출금형 예열기술 개발

민경호,배성환,최호준,신영철,Min, Kyung-Ho,Bae, Seong-Hwan,Choi, Ho-Joon,Shin, Young-Chul 한국금형공학회 2017 한국금형공학회지 Vol.11 No.1

The aim of this study is to develop the dies oven for energy-saving during the pre-heated process of extrusion dies. Applying high-efficiency near-infrared heater, single cell type dies oven was developed as a substitute for traditional chest type oven. Therefore the dies is individually heated uniformly to operation temperature so rapidly. By using the developed dies oven, electric-energy consumption of preheating extrusion dies reduced up to 30% and the waiting time in the oven also minimized up to 90min. In addition, the results have shown that it is possible to accurately control the dies temperature for improving the quality of extruded profile and to minimize die bearing oxidation and nitride layer degradation responsible for surface defects on the profile and shorter die life.

국내 금형산업 현황 및 지원정책 방향

김용대,Kim, Yong-dae 한국금형공학회 2017 한국금형공학회지 Vol.11 No.1

The domestic mold industry is composed of 6,560 small and medium sized mold companies as of 2015. The structure of mold industry centered on less than 10 people in the past has been improved in the direction of increasing number of medium and large scale companies with more than 20 competitors with global competitiveness and has maintained its position as the world's second largest mold exporter with global competitiveness. Nevertheless, the manpower structure and corporate competitiveness structure of the mold industry is very high, with the proportion of production manpower reaching 70% and shortage rate of 10% or more in order to respond to the orders of customers. However, the development base for new employees with technological skills required by the industrial field is poor, and the inflow of young people is very limited due to factors such as the avoidance of small and medium enterprises and production jobs. It is expected that the labor shortage of mold enterprises will be further increased in the future. In the mold industry, due to the characteristics of small quantity multi-product production corresponding to the demand of the consumer, many production processes are individually and independently carried out, resulting in low labor productivity, and the structural time required for the worker to increase the working time Due to limitations, the working hours per week of the employees are about 50 hours. The implementation of the working time reduction bill, which is recently promoted by the government, is a crisis factor. In order to cultivate the mold industry, it is necessary to expand the base of molds to meet the intensification of global competition, the convergence of technologies to actively respond to the restructuring of the industrial structure, and the response to the new industry, It is necessary to improve labor productivity through policies such as development and dissemination of system, and to secure price, delivery and quality competitiveness in global market.

최근 한국 금형 산업 - Part 1. 한국금형산업현황

임영택,심우필,허영무,Im, Young-Taek,Shim, Woo-Phil,Heo, Young-Moo 한국금형공학회 2018 한국금형공학회지 Vol.12 No.1

The present status of the mold industry, including the size of the mold industry in Korea, its position in the global market, the production of the mold industry, import and export, and recent trends in the mold industry were examined. The survey was implemented for the trends fo dies and molds industry in 2017 by answers on business environment for Korean Mold Industry Cooperative Union members. The sharp decline in plastic mold exports in 2015 led to a decline in overall exports. China and Japan account for a very large share of mold exporting countries, but exports to emerging markets such as India, Mexico and Vietnam contributed to the overall increase in mold exports. China, Japan, India, the United States and Mexico were named as exporting countries with more than US $ 200 million, and Vietnam showed similar tendency as a major exporter. A survey conducted by the Korea Mold Industry Cooperative Association showed that the decrease in production and exports was predicted. In order to overcome the difficulties of the mold industry, the need for research on the linkage of the mold industry and technology to the wave of the fourth industrial revolution has increased.

동일 유동거리 런너를 가진 LSR 성형품의 변형에 관한 연구

박정연,윤길상,이정원,최종명,Park, Jeong-Yeon,Yoon, Gil-Sang,Lee, Jeong-Won,Choi, Jong Myeong 한국금형공학회 2013 한국금형공학회지 Vol.7 No.1

Recently, Silicone that one of the thermo-sets is used to making optical products such as LED lenses because of excellent thermal properties. LED lenses are required to keep the precise dimensions, so they must be molded to have the minimum deformation. Thermo-sets have the expansion characteristic on the part of thermal property, it is important to optimize the cure condition so that the deformation of the part become minimum. In this study, to investigate the relationship between the shrinkage by the curing and expansion by the thermal properties of the resin, reactive injection experiment was performed by setting the variables such as mold setting temperature, cure time. As a result, it was confirmed that there was a interval while the thermal properties were transferred to more active during the cure process. It is expected to help in determining the reactive injection molding conditions of the thermo-set parts as well as LED lens in order to reduce the amount of deformation.

LED Encapsulation을 위한 스태틱 믹서의 전산 설계 및 유동해석을 이용한 액상 실리콘의 혼합 특성에 대한 연구

조용규,하석재,호소,조명우,최종명,홍승민,Cho, Yong-Kyu,Ha, Seok-Jae,Huxiao, Huxiao,Cho, Myeong-Woo,Choi, Jong Myeong,Hong, Seung-Min 한국금형공학회 2013 한국금형공학회지 Vol.7 No.1

A Light Emitting Diode(LED) is a semiconductor device which converts electricity into light. LEDs are widely used in a field of illumination, LCD(Liquid Crystal Display) backlight, mobile signals because they have several merits, such as low power consumption, long lifetime, high brightness, fast response, environment friendly. In general, LEDs production does die bonding and wire bonding on board, and do silicon and phosphor dispensing to protect LED chip and improve brightness. Then lens molding process is performed using mixed liquid silicon rubber(LSR) by resin and hardener. A mixture of resin and hardener affect the optical characteristics of the LED lens. In this paper, computational design of static mixer was performed for mixing of liquid silicon. To evaluate characteristic of mixing efficiency, finite element model of static mixer was generated, and fluidic analysis was performed according to length of mixing element. Finally, optimal condition of length of mixing element was applied to static mixer from result of fluidic analysis.