In Mold Pressure Sensing Architecture for Multi Cavity Tooling Setup
In-cavity piezoelectric pressure sensing setups in multi-cavity tools decouple fill control from hydraulic drift to minimize scrap and verify part density.
Injection Velocity Switchover
Meaning
Control algorithms in injection moulding machinery govern the transition between volumetric filling and pressure-regulated packing phases. Process control systems execute injection velocity switchover when the screw reaches a predefined position or cavity sensor threshold. Transferring control before full cavity fill prevents pressure spikes that cause tool flashing and part stress.
Modern moulding processes rely on precise switchover timing to produce consistent part weights across variable resin viscosity lots. Switching too late causes mechanical overpacking, while switching too early leaves sink marks and incomplete filling. Master process engineers establish transfer points at ninety-five percent cavity volume fill.
Process Transition
Polymer melt velocity drops abruptly as machine hydraulics transition from speed control to hold pressure control. Precise injection velocity switchover timing prevents dynamic pressure peaks from warping delicate core pins. Hydraulic response times dictate how smoothly the machine settles into hold pressure without hesitation.
High-speed thin-wall moulding applications demand transition times under ten milliseconds to avoid frozen flow fronts.
Weight Consistency
Screw position control remains the standard method for setting transfer points in stable production runs. Setting injection velocity switchover based on linear encoder position ensures repeatable shot volumes despite minor melt temperature fluctuations.
Sensor Trigger
Cavity pressure transducers provide direct feedback to trigger switchover as polymer reaches full cavity volume. Transducer-based transfer eliminates part weight variations caused by batch-to-batch resin viscosity shifts.