Design & Manufacturing

Korean Society of Die & Mold Engineering (한국금형공학회)
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Rapid cooling of injection mold for high-curvature parts using CO2 cooling module

CO2 냉각모듈을 적용한 고곡률 성형품의 사출금형 급속냉각

  • Se-Ho Lee (Dep. of Aeronautical & Mechanical Design Eng., Korea Nat'l Univ. of Transportation) ;
  • Ho-Sang Lee (Dep. of Aeronautical & Mechanical Design Eng., Korea Nat'l Univ. of Transportation)
  • 이세호 (한국교통대학교 항공.기계설계학과) ;
  • 이호상 (한국교통대학교 항공.기계설계학과)
  • Received : 2022.12.06
  • Accepted : 2022.12.31
  • Published : 2022.12.31
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Abstract

Injection molding is a cyclic process comprising of cooling phase as the largest part of this cycle. Providing efficient cooling in lesser cycle times is of significant importance in the molding industry. Recently, lots of researches have been done for rapid cooling of a hot-spot area using CO2 in injection molding. The CO2 flows under high pressure through small, flexible capillary tubes to the point of use, where it expands to create a snow and gas mixture at a temperature of -79℃. The gaseous CO2 removes heat from the mold and releases it into the atmosphere. In this paper, a CO2 cooling module was applied to an injection mold in order to cool a large area cavity uniformly and quickly, and the cooling performance of the injection mold was investigated. The product was a high-curvature molded part with a molding area of 300x100mm. Heat cartridges were installed in a stationary mold, and CO2 cooling module was inserted inside a movable mold. Through structural analysis, it was confirmed that the maximum deformation of mold with CO2 cooling module was 0.09mm. A CO2 feed system with a heat exchanger was used for cooling experiments. The CO2 was injected into the holes on both sides of the supply pipe of the cooling module and discharged through hexagon blocks to cool the mold. It took 5.8 seconds to cool the mold from an average temperature of 140℃ to 70℃. Through the experiment using CO2 cooling module, it was found that a cooling rate of up to 12.98℃/s and an average of 10.18℃/s could be achieved.

Keywords

Acknowledgement

본 연구는 2022년 한국교통대학교 지원을 받아 수행하였음.

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