Minimizing Warpage on Injection molding through Response Surface Methodology (RSM)
Sreedharan.J1, C.Manimaran2, V. Velumani3, Thirumalai Muthusamy4

1Sreedharan.J , Department of Manufacturing Engineering, School of Mechanical Engineering, VIT University, Vellore, India.
2C.Manimaran, Associate Professor, Department of mechanical Engineering, IFET College of Engineering, Villupuram, India.
3V.Velumani, Assistant Professor, Department of mechanical Engineering, Sri Nandhanam college of Engineering and Technology, Tirupattur, India.
4Thirumalai Muthusamy, Department of Manufacturing Engineering, School of Mechanical Engineering, VIT University, Vellore, India.
Manuscript received on September 23, 2019. | Revised Manuscript received on October 15, 2019. | Manuscript published on October 30, 2019. | PP: 4431-4437 | Volume-9 Issue-1, October 2019 | Retrieval Number: A1407109119/2019©BEIESP | DOI: 10.35940/ijeat.A1407.109119
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Abstract: Cosmetic defects can occur in injection molding. The aim of this study is avoidance of warpage on an injection moulding parts. The selected parts is an aesthetics part in automotive industry This study is conducted on moulded parts on the plating jigs, where warpage cannot be compensated through the fixing of parts on jigs entering plating baths where the temperature of the etching baths is around 65deg.Analysis of variance is used to determine how inputs affect outputs. The inputs used are mould surface temperature, raw material melting temperature, filling pressure and filling time. These parameters are varied to get an optimal process parameters setting to avoid the warpage of the parts by using response surface methodology. It is very difficult to understand why the warpage on the parts happens. There is lots of factors which can contribute for warpage and to identify them is a huge task and this can be due to numerous things and to sequester the role of each parameters is an uphill task. One of the parameters is the holding pressure which decides how much the part is packed which, in turn, is the cause for the stress in the part. This induced stress when gets relieved over a period of time creates warpage in the part. Warpage can also be dependent on the sequence of filling the part with various gates. For example, if the part is filled from the centre & the end gates are opened last, it may cause over packing of the part at the end & cause more warpage only at the ends locally. However, usually parts are filled in this fashion only to avoid warpage in the centre.
Keywords: Molding, Warpage, Parameters, Response surface methodology.