EPS Shape Moulding Machine Principle and Process
EPS Shape Moulding Machine Principle
The pre-hair beads after curing are heated by the steam generated by the EPS shape moulding machine, about 20 seconds to 60 seconds of time, the air is too late to escape, and pressure is generated after thermal expansion. The total pressure is greater than the vapor pressure heated outside the bead, at which point the polymer is softened and the pressure inside the bubble hole after vaporization of the foaming agent is greater than the pressure outside. The beads expand again and fill the gaps between the beads, forming a plastic foam that is the same shape as the mold.
Key molding process description
1.Boot is heated
Before starting up the EPS Molding machine to make the mold heating action, need to preheat to close the mold heating.
Reasonable adjustment of opening and closing die stroke is beneficial to improving product demodulation and product feeding effect.(push rod, die seam) slow opening gun
Steam into the solid transfer mold, preheat the mold, make the mold preheat at the same time, will remain during the condensation and cold air discharge.Function: raise the temperature of mould, strengthen the apparent fusion degree of product.
4.Through the heating
Function: improve the core and internal fusing property of products.Penetration heating consumption and steam waste are more serious.
Function: further enhance the heating effect, improve the product surface quality.
6.Return temperature (insulation)
All valves are closed to make full use of the residual heat of the mold to heat the product.It is beneficial to the surface fusion property of the product and can save energy (steam).
The water cooling valve is open and the drain valve is closed.Reasonable prolonging precooling, product cooling faster, shorten the cooling time, improve the molding speed.Generally no more than 10 seconds, precooling time is not long drying, precooling effect is much better than water cooling.
When water is cooled, the water cooling valve is opened and the drainage valve is opened.Water and air have better cooling effect together.
Vacuum valve open, vacuum pump vacuum. Make mold and products of residual heat and water all empty, take out part of the foaming agent, avoid product swelling.The forming of negative pressure inside the mold is conducive to the demoulding of the product.