• 제어로봇시스템학회:학술대회논문집
• /
• 1986.10a
• /
• pp.431-436
• /
• 1986

The design and manufacture of injection molded polymeic parts with desired mechanical properties is a costly process dominated by empiricism, including the modification of actual tooling. This paper presents an interactive computer-based design system for injection molded plastic parts. This knowledge-based synthesis system provides a rational design strategy for injection molding and molded parts. It synergistically combines a rule-based expert system for hurestic knowledge with analytical process simulation programs. The theremomechanical properties of a molded part such as the effect of molecular orientation and weldline strength are predicted by the analysis programs; while the expert system interprets the analytical results from the process simulation, evaluates the design, and generates recommendations for optimal design alternatives. The heuristic knowledge of injection molding is formalized as production rules of the expert consultation system.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2006.05a
• /
• pp.577-578
• /
• 2006

In this paper, the rubber behavior was calculated for obtaining the optimal process condition which is for producing a transformer with a given performance. This study was carried out using the computer simulation of injection mold filling and packing simulations. In order to remove the crack of product, proper locations of the runner and cooling system configurations could be determined. Based on these results, the transformer is developed by injection molding and guidelines of part design, mold design and processing conditions are established. Finally, the cast savings, cycle time reduce and improvement of productivity will be obtained.

• Korea-Australia Rheology Journal
• /
• v.19 no.1
• /
• pp.17-25
• /
• 2007

In liquid composite molding (LCM), composites are produced by impregnation of a dry preform with liquid resin. The resin flow through the preform is usually described by Darcy's law and the permeability tensor must be obtained for filling analysis. While the resin flow in the thickness direction can be neglected for thin parts, the resin flow in the transverse direction is important for thicker parts. However, the transverse permeability of the preform has not been investigated frequently. In this study, the transverse permeability was measured experimentally for five different fiber preforms. In order to verify the experimental results, the measured transverse permeability was compared with numerical results. Five different fiber mats were used in this study: glass fiber woven fabric, aramid fiber woven fabric, glass fiber random mat, glass fiber braided preform, and glass/aramid hybrid braided preform. The anisotropic braided preforms were manufactured by using a three dimensional braiding machine. The pressure was measured at the inlet and outlet positions with pressure transducers.

• Proceedings of the Korean Society for Technology of Plasticity Conference
• /
• 2005.10a
• /
• pp.423-426
• /
• 2005

The injection molding process has applied to a variety of fields by a development of various plastic resins. Recently, this process has been extending to a field of parts of shoes. In this study, the injection mold of shank which is a one of the parts of shoes has been designed. The position of gate and the injection procedure have been optimized by a simulation using the CAE software and an analysis using the DOE. As a result, the improved injection mold of shank has been manufactured in a short time. Appling the CAE and the DOE at the process of the injection mold design eventually lead an increase in the productivity and the quality of parts.

• Journal of Powder Materials
• /
• v.9 no.4
• /
• pp.261-266
• /
• 2002

CAE technology is an integrated tool including all aspects such as powder, binder system, mixing, injection molding, debinding and sintering. Therefore, CAE technology is considered as one of core technologies for PIM industry in the future. Recently many researchers are developing not only CAE software itself but also application procedures of CAE software. In this study, the applications for CAE technology in PIM industry are presented including feedstock mixing effect, several cases of troubleshooting and optimization procedure.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2008.06a
• /
• pp.464-464
• /
• 2008

This study investigated the slow cooling conditions in the molding of aspheric glass lens using the design of experiment (DOE). The optimization of the slow cooling conditions with respect to the form accuracy (PV) of the molded lens were ascertained by employing full factorial design. As a result of the analysis of variance (ANOVA) and P-value (significance level), it was verified that slow cooling rate represent the most significant operative variables that affect the corresponding response variable. In the optimum condition, the molded lens show 82% of transcription ratio.

• Journal of the Korean Crystal Growth and Crystal Technology
• /
• v.26 no.5
• /
• pp.209-214
• /
• 2016

Foam reaction injection molding (FRIM) is a widely used process for manufacturing polyurethane foam with complex shapes. Numerical model for polyurethane foam forming reaction during FRIM process has been intensively investigated by a number of researchers to precisely predict final shapes of polyurethane foams. In this study, we have identified a problem related with a previous theoretical model for polyurethane foam forming reaction. Thus, previous theoretical model was modified based on experimental and computational results.

• Proceedings of the Korean Powder Metallurgy Institute Conference
• /
• 2006.09a
• /
• pp.207-208
• /
• 2006

In this experimental work, the development of a multicomponent binder system based on high density polyethylene (HDPE) and paraffin wax for Powder Injection Molding of Alumina $(Al_2O_3)$ parts was carried out. The optimum composition of the injection mixture was established through mixing torque measurements and a rheological study. The maximum powder loading was 58 vol%. The miscibility of organic components and the optimum injection temperature was evaluated by thermal characterization of binder and feedstock. The thermal debinding cycle was developed on the basis of thermogravimetrical analysis of the binder. After sintering the densities achieved were closed to 98% of the theoretical one.

• Design & Manufacturing
• /
• v.13 no.1
• /
• pp.36-41
• /
• 2019

A large plastic molding requires an injection molding with a large clamping force. However, it could not be prepared in the manufacturing at any time. In order to solve the problem, the injection molding analysis study was conducted on the back cover of 55 inch LED TV. The study compared the case of applying the existing flow system such as hot runner, the improvement of the hot runner lay-out and the precise control of the gate operation time, From the results of using the improved flow system, it was found that the welding and the clamping force were considerably improved as compared with before the improvement. In particular, the clamping force was reduced by 50% compared with before the improvement.

• Journal of Ceramic Processing Research
• /
• v.13 no.spc2
• /
• pp.363-367
• /
• 2012

DLC (diamond liked carbon) coating of the tungsten carbide (WC) alloy core surface for molding a glass aspheric lens improves the quality of glass lens and the molding core and is characterized by high hardness, high elasticity, abrasion resistance and chemical stability. In this study, the effect of DLC coating of a thin film by means of the filtered AIP (arc ion plating) technique was examined on Ra and shape of the coated surface. Roughness before and after DLC coating was measured and the result showed that the roughness was improved after coating as compared to before coating. It was observed that DLC coating of the WC alloy core surface for molding had an effect on improving the roughness and shape of the core surface. It is considered that this will have an effect on improving abrasion resistance and the service life of the core surface.