Pop Foam is a pellet compound of the base material with the addition of expansion agents and cross linking agents to achieve the desired characteristics. The compound is then processed using precision injection equipment expressally designed for the purpose of processing the five basic polymers, being EVA, TPO’s, TRP’s, TPU’s, and PVC.

The basic process can be broken into four basic categories:

• Injection Phase
• Material Heating Phase
• Mold Opening Phase
• Post Injection Phase

The Injection Phase begins after the tooling is under clamping tonnage and can be controlled at any given segment by temperature, volume, velocity, pressure and time. The compound is injected into the tooling at about 100 degrees Celsius (material dependent) and once the pre-determined volume is reach the material flow is shut off by means of a shut off nozzle.

We then reach the Material Heating Phase of which the tooling temperature is controlled to 180 degrees Celsius (again material dependent). During this phase the compound cross linking and development of the expansion gases takes place. This phase will continue until the controlled temperature has been fully absorbed through the material in the tooling cavity.

The Opening Phase is when the mold half’s separate at a rapid speed and allows the compound to expand to the parts final geometry. This rapid opening is accomplished by means of an accumulator on the equipments clamping system.

The Post Injection Phase is when the part leaves the specialized injection equipment. Due to the elevated procession temperatures the product leaves the equipment extremely soft and presents an over expanded ratio. With this phase the product will return to normal valves as represented on the specification sheets. Keep in mind these compounds represent excellent insulating properties; therefore we must progressively cool the product in precisely controlled cooling ovens to maintain significant differences between the products internal and externally temperatures. This Post Injection Phase assures the products proper size and dimensional stability. All of the above categories are critical to control the products Expansion Ratio, Density, Elongation, Size, Dimensional Stability, Shrinkage and Cosmetic Appearances.

    40 Ton 10 Station Machine