Process control on injection molding machines - What is the correct hydraulic response during switchover from 1st to 2nd stage?

Correct process control is critical for making identical parts to tight tolerances and meeting numerous quality standards. This study focuses on the switchover time as an injection molding machine transfers from first to second stage and its impact on part quality. Hydraulic pressure responses are adjusted in both closed loop and open loop modes while cavity pressure is monitored to verify effects on plastic pressure. Results are also presented for best modes of filling and packing to build proper cavity pressure to assure robust processing window.