PRE-EXPANDERS

Fully automatic pressure batch type process operation. Automatic dosing of raw material.
Expander design provides efficient operation for EPS, PMMA and most copolymers.
High throughput yielding more processed beads per pre-expander, providing lower operating and capital cost.
Vacuum conveyance of raw material to upper storage hopper.
Stainless steel raw material storage and weighing hoppers.
Transparent raw material dosing funnel allows visual inspection of material flow. Transparent expansion chamber enables visual monitoring of the material expansion.
Variable speed, stainless steel agitator stirrer with Teflon wipers insures delicate bead treatment while in the expansion chamber.
Live steam controlled by a proportional steam regulator is introduced into expansion chamber through a fine mesh stainless steel diffuser screen. Direct steam contact on raw material provides uniform expansion of beads.
Purge valve on expansion chamber allows continuous cross flow of steam through raw material for more uniform temperature throughout the expansion chamber.
Photoelectric eye senses pre-expanded bead level in chamber which stops the expansion process at a known volume to assure precise density control.
Quick evacuation of expanded beads through fully open expansion chamber bottom. Fluidizing bead drying bed allows precision cooling and stabilizing of expanded beads.
Screen type bead de-lumping system. Two stage vibrating sieve unit provides bead classification and elimination of dysfunctional (dead) beads.
Programmable controller containing fully functional integrated software for machine control allowing operator easy and simple adjustment of all process timers.