Inside EPS raw beads, there’s the blowing gas called pentane. After steaming, pentane starts to expand so the bead size also grows bigger, this is called expanding. EPS raw beads cannot be used to make blocks or packaging products directly, all beads need to be expanded first then make other products. Product density is decided during Preexpanding, so density control is done in Preexpander.

Thermocol batch expander machine is functioned to expand EPS raw material to required density. Material filling and expanding is done batch by batch, so it’s called Batch pre-expander. Automatic polystyrene beads expanding machine is a type of full automatic EPS machine, all steps are working automatically like EPS material filling, weighing, material conveying, steaming, stablizing, discharging, drying and expanded material conveying.
Comparing with Continuous Preexpander, thermocol batch expander machine can give more accurate density, easier operation, and more energy saving.
Thermocol batch expander machine completes with Screw Conveyor, Weighing System, Vacuum Conveyor, Expansion Chamber, and Fluidized bed Drier

Thermocol batch expander machine advantage:
1.Batch Preexpander adopts Mitsubishi PLC and Winview touch screen to control whole working automatically;
2.Batch Preexpander use vacuum system to convey raw material from bottom to top loader, no blocking material hose and no breaking EPS beads;
3.In some machine models, there’re two top loaders for filling alternatively, saving power and fast in filling;
4.Machine first expansion and second expansion both uses PT650 electronic weighing meter to control weighing, accuracy to 0.1g;
5.Machine uses Japanese Pressure Reducing Valve to ensure stable steam input;
6.Machine with preheating and main steaming. Using small valve to do preheating till certain temperature then do main heating, so material can be expanded properly;
7.Machine control steam and air pressure properly inside expansion chamber, material density tolerance lower than 3%;
8.Machine agitating shaft and inner expansion chamber are all made of SS304;
9.Steam proportional vale, air proportional valve and Korean vibration sensor are optional.