During pre-expansion, the EPS resins are fed to a vessel containing an agitator and controlled steam and air supplies, this vessel is called EPS Pre-expander, or EPS Batch Pre-expander Machine. The diameter of the particles increases while the density of the resin decreases. After exiting from the EPS pre-expander, the expanded beads will flow through a dryer to remove moisture, and then go to aging silo.
A. Body of EPS Batch Pre-expander
• Expansion chamber is made of SUS 304 stainless steel, cylindrical shape with insulation layer.
• Agitator is made of SUS 304 stainless steel, rotation speed is fixed
• Discharge door located on the side of the vessel, to empty the chamber fast.
• Safety fence to top.
B. Screw Loading system
A screw loading machine with a tank ( approx. 1.5 m3 volume , 1200kg EPS beads) is using to load EPS resin to Dosing unit. And then filling to the expansion chamber by gravity.
C. Fluid bed dryer
Inside floor parts made of aluminium with slots, The dryer is equipped with a steam-air heat exchanger inside, which avoid the beads from thermal shock. At the end of dryer, there is a Venturi tube system to send EPS beads to specified silos.
D. 2nd Expansion Unit
2nd expansion system is available for this EPS pre-expander to get lower density. The PLC control the 2nd expansion in a fixed volume. The filling from the silo to the machine is done by a vacuum fan.
E. Control Panel
Main cabinet,with security lock,is equipped with Delta touch screen and PLC.
All parameters and recipes can be added, revised and saved in PLC.