Effect of bottle handle design on injection molding production parameters and usage performance

Abstract

The trial and error method traditionally used in injection molding machines can lead to losses in terms of time and cost for the determination of process parameters. This method cannot guarantee an optimum result. Therefore, computer-aided engineering software for plastic flow analysis has become an important tool for optimizing injection molding processes. This software helps to optimize the process parameters used in the production of plastic parts through the simulation of plastic flow. Simulation consists of a series of steps, starting from the design of the plastic part, through the design of the injection mold, material selection, determination of process parameters and finally validation of the production process. In this way, all parameters are optimized before production, making the injection molding process efficient and cost-effective. The use of plastic flow analysis software improves the performance of injection molding machines and reduces the number of defective products. This means that the production process produces less waste and production time is reduced. Furthermore, this software can be used to quickly analyze the effects of changes in product design and mold design on the injection molding process. As a result, computer-aided engineering software that performs plastic flow analysis enables the optimization of injection molding processes in a faster, more accurate and cost-effective way instead of the trial-and-error method in injection molding machines. In this study, the moldability characteristics of different gate concepts, injection filling points and gate diameters affecting the production parameters of water bottle handles produced by plastic injection molding method were investigated. Based on the production values obtained, appropriate choices were made for the handling performance of water bottles. The handle is made of High Density Polyethylene (HDPE) material to facilitate the transportation of water bottles. By determining the optimum values of parameters such as melting temperature, molding temperature, injection time, holding pressure, holding time, cooling time of the material, the results of Filling time, Filling Pressure Analysis, Temperature Analysis, Frozen Layer Analysis and Joint Line Analysis were obtained by using the Moldflow program on 3D models of bottle handles. As a result of these analyses, the best gate concept and gate diameter for the best gate filling zone were determined and evaluated in terms of usage performance and manufacturability. As a result of the analysis for the same process parameters, the optimum production parameters were reduced to the final two by considering the optimum parameters in breaking force and molding. Although the first design has the highest breaking force, it is not suitable for mass production due to the weight increase of 12.1%. It was concluded that the second design should be approved as it provided a 44.4% increase in breaking force while the handle weight increased by 2.1%.

Keywords

• Injection molding
• Moldability analysis
• Injection fill point analysis
• Plastic flow analysis
• Gate System

References

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