Electrohydraulic proportional directional control valves from Atos Spa (below) provide closed-loop flow and pressure control, which lends itself to injection molding, metal die casting (above) and presses. The dual control moves actuators quickly into position to minimize machine cycle times, then provides pressure control to ensure tight process control.
Die casting and injection molding machines place some hefty demands on hydraulic systems. They must operate with high repeatability to ensure high product consistency and low scrap rate. But first and foremost, they must operate with the highest possible throughput to maximize productivity in order to minimize cost per part. And don’t forget reliability, which is a big reason why hydraulics is used so often in these applications.
A key to a machine’s high productivity lies with the motion control system of its main hydraulic cylinder — which injects molten metal or plastic into a die cavity. The challenge is to move the cylinder’s piston rod quickly during non-injection portions of a cycle while offering precise pressure control near the end of an injection cycle to ensure high quality and consistent parts.
Electrohydraulic proportional directional control valves with pressure and flow (P/Q) from Atos Spa, Sesto Calende, Italy, lend themselves to the requirements of plastic injection molding, metal die casting, and cushion control of vertical presses.
