The ZSE-27 MAXX “direct to sheet” system facilitates rapid in-line compounding and production of prototype sheet samples. Benefits of direct sheet extrusion include the product having one-less heat/shear history, and economic savings inherent with bypassing the pelletization step. The following components will comprise the system:
ZSE-27 MAXX co-rotating, intermeshing, twin screw extruder:
- 52/1 L/D with modular barrels and segmented screws
- 1.66/1 OD/ID ratio for screw
- 40 kW water-cooled motor
- Q2 LSB-26 side stuffers for filler/fiber introduction
- Allen-Bradley Compact Logix L3 PLC with PanelView Plus 15” touch screen HMI
Gear pump front-end attachment with 20 cc/rev capacity and 5 HP AC motor
14” Sheet/film flex-lip die
3-Roll sheet/film system with the following features:
- (3) 8” diameter by 16” wide rolls with linear motion and individual 1 HP AC motors/drives
- Driven rotary shear edge-trimming
- Dual unwinds for extrudate lamination/encapsulation utilizing magnetic particle brakes
- Integral, center driven rewind with automatic gap control and closed loop tension control
- Air expanding chucks on rewind and unwind shafts
- Allen-Bradley CompactLogix L2 PLC with touch-screen HMI
- PLC distributive processing control architecture: Distributive processing refers to whensub-processes are controlled by a discrete PLC, and a master-PLC is used to manage the over-all system and consolidate recipe management and data acquisition. This is particularly important when integrating systems from multiple suppliers with distinctly different technologies.
The ZSE-27 MAXX twin screw extruder system and downstream lamination system each have their own PLC and HMI interface. These two systems can operate independently or together via an Ethernet communications link to allow fully integrated system sharing of recipe, data acquisition and logic/alarming.
- Pressure control algorithm: Typically the gear pump RPM is locked to set a constant volumetric rate to the die. The tuning algorithm in the PLC analyzes the inputs from key points in the system, makes numerical calculations, and applies corrections to the extruder screw RPM and feed rate to maintain the gear pump inlet pressure at a given set point.
Other direct extrusion capabilities in the Leistritz process laboratory include:
- ZSE-50 MAXX twin screw extruder and 40 inch wide film/sheet downstream system
- Coextrusion capabilities: AB, ABA, ABC and ABCBA
- Tube/profile downstream system