Principle and process of EPS profile forming machine
Principle of EPS Profile Forming Machine
The cured pre-expanded beads are heated by the steam generated by the EPS forming machine. For about 20 seconds to 60 seconds, the air has no time to escape, and the pressure is generated after thermal expansion. The total pressure is greater than the vapor pressure of the external heating of the beads. At this time, the polymer softens, and the pressure in the cells after the blowing agent evaporates is greater than the external pressure. The beads expand again and fill the spaces between the beads, forming a plastic foam that is the same shape as the mold.
Principle and process of EPS profile forming machine
Button molding process description
1. Turn on the heating
Before starting the EPS molding machine for mold heating, it is necessary to preheat and turn off the mold heating.
2. Clamping
Reasonable adjustment of the mold opening and closing stroke is conducive to improving the effect of product demodulation and product feeding. (push rod, die seam) slow fire
3. Preheat
The steam enters the solid transfer mold, preheats the mold, and at the same time makes the mold preheat, condenses and cools air out of the process residue. Function: increase the temperature of the mold and strengthen the apparent fusion of the product.
4. By heating
Function: Improve the core and internal melting performance of the product. Penetration heat loss and steam waste are more serious.
5. Two-way heating
Function: further enhance the heating effect and improve the surface quality of the product.
6. Reflow temperature (insulation)
Close all valves and make full use of the waste heat of the mold to heat the product, which is beneficial to the surface fusion of the product and saves energy (steam).
7. Pre-cooling
The water cooling valve is opened and the drain valve is closed. Reasonably extend the pre-cooling time, the product cooling speed is faster, shorten the cooling time, and increase the molding speed. Generally no more than 10 seconds, the pre-cooling time is not long for drying, and the pre-cooling effect is much better than water cooling.
8. Water cooling
When the water cools, the water cooling valve opens and the drain valve opens. Water and air cool together better.
9. Vacuum cooling
The vacuum valve is opened and the vacuum pump draws a vacuum. Evacuate the residual heat and water of the mold and product, and take out part of the foaming agent to avoid product expansion. Negative pressure is formed inside the mold, which is conducive to product demoulding.