Development of runner reservoir and its effect on optical properties of small high-precision plastic injection molded parts

Demitri Shotwell, Mong Tung Lin, Jia Hau Liu, Lih Sheng Turng*

*Corresponding author for this work

Research output: Contribution to journalJournal Article peer-review

Abstract

Adding reservoirs as extensions to a multi-cavity runner-system to regulate cavity fill-rate within small, high-precision optical parts during filling and fill-to-pack switch-over (F/P) was studied with the aid of simulations. This work aimed for a constant melt-front velocity inside the cavities with varying geometries. Three methods of reservoir designs were considered: first, using engineering intuition, second and third, using mass balance and mass and momentum balance equations, respectively. Eight reservoirs were designed and compared to two no-reservoir cases. For each case, 27 runs covering three levels of fill-rate, F/P, and packing pressure were simulated, resulting in 270 simulation runs. The quality variables of flow and thermally induced retardation and the average and standard deviation of volumetric shrinkage were considered and for each parameter, the minimum, best cases, occurred with a reservoir case. Thus, this study offers a proof-of-concept design for using reservoirs to improve molding of small, high-precision optical parts.

Original languageEnglish
Pages (from-to)330-345
Number of pages16
JournalPlastics, Rubber and Composites
Volume52
Issue number6
DOIs
StatePublished - 2023
Externally publishedYes

Bibliographical note

Publisher Copyright:
© 2023 Institute of Materials, Minerals and Mining Published by Taylor & Francis on behalf of the Institute.

Keywords

  • Injection molding
  • birefringence
  • mold and runner reservoir design
  • plastic optics
  • retardation
  • simulation

Fingerprint

Dive into the research topics of 'Development of runner reservoir and its effect on optical properties of small high-precision plastic injection molded parts'. Together they form a unique fingerprint.

Cite this