A Study on Hopper Design for Minimizing the Wrapage Deformation at Injection Molding Processes

사출공정에서 휨 변형을 최소로 하는 호퍼 설계 연구

  • Kim, Young-Suk (School of Mechanical Engineering, Kyungpook National University) ;
  • Lee, Eui-Joo (Graduate School, Kyungpook National University) ;
  • Son, Jae-Hwan (Daegu Mechatronics and Material Institute)
  • Received : 2014.08.14
  • Accepted : 2014.01.08
  • Published : 2015.01.31


Injection molding is a high efficient manufacturing technology for producing plastic parts. On the other hand, the warpage of molded plastic parts is an ubiquitous problem in the injection molding process. The main objective of this study was to minimize the amount of warpage occurring in the injection molding process of a hopper of ATDPS made of crystalline polymer (PP) instead of amorphous polymer (ABS). The moldflow CAE simulation was conducted for the molding process of the hopper to clarify the injection moldability, shear rate, shear stress, warpage by changing the gate shape and the number of ribs installed on the top of the hopper flange. The wide gate shape of runner system and multiple rib installation were found to be useful for minimizing the warpage of the hopper. The validity of the CAE simulations was supported by the injection molding experiment for the optimized design case.


Supported by : 경북대학교


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