METHOD OF MOLDING LARGE THIN PARTS FROM REINFORCED PLASTIC MATERIAL

摘要

Reinforced plastic pellets comprise thermoplastic material and reinforcement particles that are less than 15 % of a total volume of the pellets, and at least 40 % have a thickness of less than 50 nanometers. A manifold (56) has at least two spaced valve gates (64) that are independently opened and closed as directed by a controller (68) to selectively communicate the manifold to a cavity. A primary injection pressure is applied to the plasticized pellet material in the manifold (56) to fill the cavity through sequential opening and closing of the gates (64). A lower secondary injection pressure is applied to the material in the manifold to continue filling the cavity. The gates are closed to seal the manifold from the cavity when the cavity is filled. The material is held within the manifold in compression by the valves while the cavity is open to prevent expansion of the material.