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Analysis of the Physical Quantity Variation in the Cavity and the Quality of the Molded Product According to the Injection Speed in Injection Molding

  • Kwon, Soon Yong (Samyang Central R & D Center) ;
  • Cho, Jung Hwan (Samyang Central R & D Center) ;
  • Roh, Hyung Jin (Samyang Central R & D Center) ;
  • Cho, Sung Hwan (Samyang Central R & D Center) ;
  • Lee, Yoo Jin (Department of Mechanical System Design Engineering, Seoul National University of Science and Technology) ;
  • Lyu, Min-Young (Department of Mechanical System Design Engineering, Seoul National University of Science and Technology)
  • Received : 2017.12.03
  • Accepted : 2017.12.14
  • Published : 2017.12.31

Abstract

Molding conditions can be described as factors that determine the quality of a product obtained from injection molding. Many studies have been performed on the injection molding pressure, injection temperature, packing pressure and other molding conditions related to part quality. However, the most accessible factor among the adjustable molding conditions during actual injection is the injection speed. In this study, we simulated the variation of the physical quantity according to injection speed and performed experiments to understand the effect of injection speed on the actual product. A CAE analysis program (Moldflow) was used to simulate and analyze the results using PC and PBT for two models. In order to compare these results with the experimental results, an actual injection molding was performed for each injection speed, and the correlation between simulation and injection molding, especially for the shrinkage of the molded article, was discussed.

Acknowledgement

Supported by : 서울과학기술대학교

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