Injection molding is a plastic forming process by way of melting
the plastic material is injected into a mold (mold). Defects that often occur
in injection molding products include a short shot, Sink mark, flash and
warpage. The causes of warpage is affected by the injection pressure,
mold temperature, melting and holding time in the plastic injection process
(Huang and Tai, 2001). Therefore, the purpose of this study was to
investigate the influence of the holding time of the occurrence of defects
warpage of the results of injection molding products and to determine the
proper holding time parameter to obtain the optimal product of injection
molding.
The initial step of making the mold (mold) with CNC milling
machines and manufacture of cooling systems softooling type of conformal
cooling channels. Toling soft system is made by mixing powdered
aluminum and epoxy glue in the ratio 2: 1 channel conformal printed
therein. The data collection method used is processing images with image
capture using a 14 pixel camera and processed using software solidwork
and warpage measurement with a dial indicator measuring devices that
can be analyzed statistically and can be drawn to a conclusion.
From the results of the study concluded that in this study
generally increase the holding time making warpage percentage that
increasingly smaller and smaller and even disappear and vice versa.
Optimal holding time of this analysis, the holding time of 12.5 seconds.
Keywords: injection molding, solidwork, dial indicators, hold time,
warpage
