• 소성∙가공
• /
• 제16권1호
• /
• pp.31-35
• /
• 2007

Automotive weather strip should have good weather ability, sealability, durability, etc. to perform its duty as body sealing for vehicles under different harsh environments. Due to its comprehensive properties, thermoplastic vulcanizate(TPV) is widely employed in weather strip as alternative for ethylene propylene diene rubber(EPDM). In this study, the influences of the recycled TPV on the tensile strength and hardness were investigated. As results of the injection molding experiment, the recycled TPV's tensile strength and hardness were higher than the virgin TPV and recycled TPV's extension was improve. The morphology showed that recycled TPV's rubber particles became smaller than virgin TPV's rubber particles.

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

• 한국생산제조학회지
• /
• 제23권2호
• /
• pp.206-212
• /
• 2014

Liquid silicone rubber (LSR) has been widely used in automotive, electrical, and medical components. Thus, research on the use of LSR in the injection molding process is required to obtain high-quality and high-performance products. In this study, a mold was fabricated to examine the effects of the process parameters on the molding and mechanical properties of LSR parts. A computer-aided engineering analysis was used to optimize the air vent depth and curing temperature to decrease the flash at the air vents caused by the low viscosity of LSR. Temperature and pressure sensors were mounted in the mold to determine the effects of the process parameters on the temperature and pressure in the cavity. The tensile strength of the LSR parts was also examined in relation to the process parameters.

• 한국정밀공학회지
• /
• 제16권4호통권97호
• /
• pp.110-115
• /
• 1999

The surface gloss of an injection molded part is one of the most significant point for evaluating the quality of products appearance. The effects of process condition on the gloss of ABS(Acrylonitrile-Butadiene-Styrene) molded part were investigated in this work. The measurements of gloss and morphology on the surface of molded part were carried out with different melt temperature, mold temperature, mold surface roughness, injection pressure and holding pressure. Gloss had a maximum value with melt temperature in the range of 210 to 220 ${^\circ}C$ and with mold temperature 40 to 50${^\circ}C$ and with injection pressure 80~90 MPa, respectively. Melt temperature was shown to have the largest effect on gloss in our work. Gloss was not improved in the region of melt temperature 240${^\circ}C$ above and of mold temperature 60${^\circ}C$ above. It was concluded that the variation of gloss was mainly caused by rubber particles migration under shear stress not by their aggregation or necklace.

• International Journal of Precision Engineering and Manufacturing
• /
• 제7권4호
• /
• pp.23-27
• /
• 2006

Rubber is used in many industrial products, such as hoses, rubber belts, and oil seals. In particular, more than 200 rubber parts are used in automobiles. The design technology of these parts is largely dependent on field experience, which leads to lengthy and expensive developing procedures. However, with the help of recent developments in nonlinear computer analysis, new rubber products can be developed at low cost. In this study, rubber injection molding design variables, such as location and number of gates, were optimized using computer-aided engineering with the cross-WLF equation to produce CLIP rubber products made from ethylene propylene diene monomer(EPDM). The validity of the proposed design was evaluated by comparison with actual forming results.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2000년도 추계학술대회 논문집
• /
• pp.653-657
• /
• 2000

The paper describes the contents and results of the national project named "Development of Computer Integrated Product Design for Automation Equipment". It is focussed on the real-time control '||'&'||' monitoring of manufacturing process for automobile rubber parts. Automobile rubber parts industy is one of the typical process that high11 depends upon manufacturing facilities and equipments. So. it requires high cost and engineering technolog) on plant implementation. But most companies of rubber parts industries are small or mid companies that habe weak abilities for plant implementation properly and systematically. Therefore, for upgrading the levelof automation. it is necessar). to dekelope the computer based management and monitoring slsteni that enables to build-up the common base of automation and systemization. 'Through this project. we developed low cost real-time monitoring system for banbun mixing process '||'&'||' mold injection process of rubbcr parts manufacturing, that is composed with DDCU(Distributed Digital Control Unit),signal interfaces to gathering mon~toring terms and speciall\ developed functional sofhare including some algorithm for management '||'&'||' process monitoring

• Elastomers and Composites
• /
• 제51권4호
• /
• pp.275-279
• /
• 2016

Additive manufacturing or 3D printing is a new manufacturing process and its application is getting growth. However, the product qualities such as mechanical strength, dimensional accuracy, and surface quality are low compared with conventional manufacturing process such as molding and machining. In this study not only mechanical characteristics of polymer sandwich panel having three dimensional core layer but also mechanical characteristics of core layer itself were analyzed. The shape of three dimensional core layer was pyramidal kagome structure. This core layer was fabricated by two different methods, injection molding with PP resin and material jetting type 3D printing with acrylic photo curable resin. The material for face sheets in the polymer sandwich panel was PP. Maximum load, stiffness, and elongation at break were examined for core layers fabricated by two different methods and also assembled polymer sandwich panels. 3D printed core showed brittle behavior, but the brittleness decreased in polymer sandwich panel containing 3D printed core. The availability of 3D printed article for the three dimensional core layer of polymer sandwich panel was verified.

• 한국산학기술학회논문지
• /
• 제14권5호
• /
• pp.2092-2099
• /
• 2013

현재 광디스크 드라이브는 오랜 기간 지속된 산업계의 데이터 전송률 경쟁을 통하여 10,000 rpm 이상의 고속으로 구동되고 있다. 고속 구동은 필연적으로 시스템의 진동을 유발하여 픽업의 데이터 읽기/쓰기 서보 제어에 외란을 야기하는데, 통상 진동외란은 방진고무를 통한 진동의 절연 및 서보 제어의 강인성 개선을 통해 해결되고 있다. 본 연구에서는 산업계에서 일상으로 이루어지는 광디스크 드라이브 시스템의 동특성 개선에서 한걸음 더 나아가 광디스크의 동특성을 개선하는데 주목하였다. 이를 위하여 사출성형 공정해석을 수행하여 공정 조건(유량, 사출온도)이 잔류응력에 미치는 영향을 조사하였고, 이 잔류응력의 변화가 광디스크의 진동 모드 및 임계속도 즉, 동특성에 미치는 영향을 모달해석을 통해 살펴보았다. 이러한 일련의 과정을 통해 사출성형 시 발생하는 광디스크의 잔류응력을 제어하여 광디스크의 임계속도를 잔류응력이 없는 경우 대비 약 14.4% 높일 수 있음을 확인하였다.

• Design & Manufacturing
• /
• 제7권1호
• /
• pp.60-63
• /
• 2013

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.

• 한국추진공학회:학술대회논문집
• /
• 한국추진공학회 2010년도 제35회 추계학술대회논문집
• /
• pp.707-710
• /
• 2010

KSLV-I 킥모터 노즐 개발에 있어서 가장 중요한 개발품은 노즐 구동에 필요한 플렉시블 씰 개발이다. 특히 플렉시블 씰 제작 기술의 확보는 킥 모터 노즐 개발에 있어서 핵심 개발 사항 중에 하나였다. 킥모터 플렉시블 씰 제작에 사용된 방법은 금형에 순서대로 배열된 보강재 사이에 고무를 주입하는 인젝션 방식을 사용하였다. 플렉시블 씰 제작을 통해 금형 설계 기술, 고무 인젝션 방법, 성형 공정을 확립하였다. 제작된 플렉시블 씰은 X-Ray 검사를 통해 내부 접착 상태 및 보강재/고무 배열 상태를 확인하였다.