Warpage Analysis of Injection Molded Thin-Walled Chassis Part by RSM and FEM

Year 2020, Volume: 1 Issue: 2, 63 - 70, 01.06.2020

Uğur Demirci Mirigül Altan

Abstract

Warpage is one of the common defects seen in thin-walled injection moldings. There are several ways to reduce
warpage in injection molding process such as optimizing process conditions, changing mold design or part
design. In this study, warpage of the injection molded thin-walled chassis part of an air conditioner was
investigated by finite element method (FEM) and response surface method (RSM). The material was
polypropylene with 20% glass fiber and 4% chemical foaming agent. The key parameters in FEM analysis and
RSM were cooling time, mold temperature and flow rate of the coolant. It has been seen that mold temperature
was the most significant parameter on warpage. RSM and FEM were satisfactorily successful in predicting the
warpage values.

Keywords

Plastic Injection Molding, Thin-Walled, Warpage, Finite Element Analysis, Response Surface Method.

References

• [1] Wang, G., Zhao, G., Li, H. & Guan, Y. (2011). Research on optimization design of the heating/cooling channels for rapid heat cycle molding based on response surface methodology and constrained particle swarm optimization, Expert Systems with Applications, 38(6), 6705-6719.
• [2] Dang, X.P. (2014). General frameworks for optimization of plastic injection molding process parameters, Simulation Modelling Practice and Theory, 41, 15-26. [3] Kuram, E., Tasci, E., Altan A.İ., Medar, M.M., Yilmaz F. & Ozcelik, B. (2013). Investigating the effects of recycling number and injection parameters on the mechanical properties of glass-fibre reinforced nylon 6 using Taguchi method, Materials and Design, 49, 139-150.
• [4] Ozcelik, B., Kuram, E. & Topal, M.M. (2012). Investigation the effects of obstacle geometries and injection molding parameters on weld line strength using experimental and finite element methods in plastic injection molding, International Communications in Heat and Mass Transfer, 39(2), 275-280.
• [5] Zhang, S., Dubay, R. & Charest M. (2015). A principal component analysis model-based predictive controller for controlling part warpage in plastic injection molding, Expert Systems with aplications, 42(6), 2919-2927. [6] Wang, C., Huang, M., Shen, C. & Zhao, Z. (2016). Warpage prediction of the injection-molded strip-like plastic parts, Chinese Journal of Chemical Enginerring, 24(5), 665-670.
• [7] Oliaei, E., Heidari, B.S., Davachi, S.M., Bahrami, M., Davoodi, S., Hejazi, I. & Seyfi, J. (2016). Warpage and Shrinkage Optimization of Injection-Molded Plastic Spoon Parts for Biodegradable Polymers Using Taguchi, ANOVA and Artificial Neural Network Methods, Journal of Materials Science & Technology, 32(8), 710-720.
• [8] Niana, C.S., Wu C.Y. & Huang W. (2015). Warpage control of thin-walled injection molding using local mold temperatures, International Communications in Heat and Mass Transfer, 61, 102-110.
• [9] Yen, C, Lin, J.C., Li, W. & Huang, M.F. (2006). An abductive neural network approach to the design of runner dimensions for the minimization of warpage in injection mouldings, Journal of Materials Processing Technology, 174, 22–28.
• [10] Huang, M.C. & Tai, C.C. (2001). The effective factors in the warpage problem of an injection-molded part with a thin shell feature, Journal of Materials Processing Technology, 110(1), 1-9. [11] Altan, M. (2010). Reducing shrinkage in injection moldings via the Taguchi, ANOVA and neural network methods, Materials & Design, 31, 599-604.
• [12] Liao, O. & Liu, S. (2009). Effect of Packing Parameters on Warpage of Moulded Part during Injection Moulding, Plastics Science and Technology, 37(10), 67–69.
• [13] Ozcelik, B. & Sonat, I. (2009). Warpage and structural analysis of thin shell plastic in the plastic injection molding, Materials & Design, 30(2), 367–375.
• [14] Erzurumlu, T. & Ozcelik B. (2006). Minimization of warpage and sink index in injection-molded thermoplastic parts using Taguchi optimization method, Materials & Design, 27, 853–861.
• [15] Demirci, U. Köpük Ajanı İçeren Polipropilenin plastik enjeksiyon kalıplanmasında çarpılmanın ve çevrim zamanının optimizasyonu, Yildiz Technical University, Graduate School Science and Engineering, Master Thesis, June 2019