Design & Manufacturing

Korean Society of Die & Mold Engineering (한국금형공학회)
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Analysis of impingement mixing for coating in injection mold

사출금형 안에서 코팅을 위한 충돌혼합에 관한 해석

  • Kim, Seul-Woo (Dep. of Aeronautical & Mechanical Design Eng., Korea Nat'l Univ. of Transportation) ;
  • Lee, Ho-Sang (Dep. of Aeronautical & Mechanical Design Eng., Korea Nat'l Univ. of Transportation)
  • 김슬우 (한국교통대학교 항공.기계설계학과) ;
  • 이호상 (한국교통대학교 항공.기계설계학과)
  • Received : 2019.12.11
  • Accepted : 2019.12.31
  • Published : 2019.12.31
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Abstract

In-mold Coating is a method that can simultaneously perform injection molding and surface coating in injection mold. The material used for coating is two-component polyurethane which is composed of polyol and isocyanate. L-type mixing head can be used to mix polyol and isocyanate uniformly, and inject them inside the mold cavity. The surface quality of the injection molded products by using in-mold coating depends on the mixing uniformity between main agent and hardener. In this study, flow analysis was performed to design a mixing head for uniform mixing of two-component polyurethane. Especially the effects of design parameters of mixing head on mixing uniformity and nozzle pressure were investigated. The parameters of mixing head were mixing chamber diameter, cleaning cylinder diameter, nozzle alignment angle in the horizontal and vertical direction, and cleaning piston position. It was found that optimal design values were mixing chamber diameter of 3.5 mm, cleaning cylinder diameter of 5.0 mm, nozzle horizontal/vertical alignment angles of 140°/160°, and cleaning piston position of 1.8 mm. The optimal values would be used to develop a two-component mixing head achieving an uniform mixing for in-mold coating.

Keywords

Acknowledgement

Supported by : 한국연구재단

본 연구는 2019년 한국교통대학교 지원을 받아 수행하였으며, 또한 정부(교육부)의 재원으로 한국연구재단의 지원으로 수행되었습니다.(No.2018R1D1A3B07045339)

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