Method for molding products from particulate polymeric material

In a method for molding products in a mold cavity formed by a male and female mold element which method includes the steps of closing the mold elements to form the cavity, heating said elements, filling said cavity with polymeric beads, injecting steam into the cavity and cooling said elements, the improvement in said method comprising:

• a. simultaneously introducing steam into both of said mold elements through spaces or channels therein while closing said elements to form said cavity;
• b. terminating the direct introduction of steam into said female mold element during mold element closing when steam begins to discharge from said male mold element and directing the steam discharged from said male mold element into the female mold element;
• c. filling said cavity with said polymeric beads;
• d. terminating the discharge of steam from said female mold element not later than the injection of steam into said mold cavity;
• e. injecting steam into the mold cavity to mold said product;
• f. terminating the introduction of steam into said male mold element and directly introducing into each of said mold elements a cooling fluid and permitting said fluid to separately flow through each of said elements;
• and
• g. terminating said flow of cooling fluid, opening said mold elements and removing said molded product.