SE-DUZ Series Injection Unit Features

Sumitomo (SHI) Demag's new SE-DUZ direct-drive all-electric injection molding machines offer an even wider choice of injection units than the predecessor SE-DU Series. This selection of injection units combined with the advanced, low inertia design of the injection unit's direct-drive motors provide:

• High injection power (torque) and velocity - with injection speeds up to 500mm/sec, and injection pressures up to 2900 kgf/cm² for the most demanding applications
• Unerring velocity control from .01 mm/sec to the maximum velocity, for improved precision on wide range of parts including thick-wall lenses, visually critical and thin-wall parts
• Faster velocity response, unaffected by belt elasticity, well-suited for narrow pitch connectors, micro-sized parts and other parts with extremely tight tolerances

This diagram shows the compact, low-inertia, direct-drive configuration of the SE-DUZ injection unit. The motor for injection uses a load cell to provide feedback that dictates the speed and torque required for precision injection pressure. The screw drive motor works together with a position transducer.

The high torque of the direct-drive, screw drive motor, as compared with a belted motor, is a particular advantage for high-viscosity resins. And compared with a hydraulic machine, the SE-DUZ requires fewer control devices because there are no proportional and directional valves needed to control hydraulic flow and pressures.

Working together with the new Z Control, the SE-DUZ delivers improved precision with low-pressure filling. The Z's patent-pending Flow Front Control (FFC) System optimizes the flow front, further allowing control of low internal pressures inside the cavities. This system:

• Takes advantage of the viscoelastic properties of the resin — visco (creep) and elasticity (recovery or pull back) — and allows complete filling without flash
• Provides precision control of screw position to ensure consistent filling, shot-to-shot
• Avoids overfilling, allowing gases to be released and preventing short shots

The SK-II, the industry's most advanced injection control, is also available to help molders achieve the highest levels of injection fill precision and peak pressure stability. (Control software standard; screw tip optional.)

Superior temperature control, provided by the following features, is another advantage of the SE-DUZ:

• Double-shield barrel cover
• Heater burnout monitor
• Temperature control for the nozzle is standard
• Synchronized heat-up
• Water cooling jacket temperature control device

Other SE-DUZ injection unit features include:

• Programmable switchover from velocity to hold - selectable by position or pressure
• Hold pressure settable and accurate to 1kgf/cm² from 0 to 2400 depending on machine size
• Flash speed mode, designed for injection speeds of 300mm/sec and higher, provides fast response control of velocity and pressure, before and after V/P switchover. It is used to prevent short shots and warp from over-packing.
• Synchro-plast control mode, a standard feature, is ideally suited for resins with low viscosity or uneven pellet size. In this mode, control of both the screw position and back pressure are optimized, ensuring plasticizing stability.
• PID temperature control system that optimizes melt conditions with 2-second sampling and 0.1°C settable barrel zones

For specifications and to read more about SE-DUZ Series injection molding machines, please use the Info buttons above at the right.