TWO STAGE SYSTEM AND METHOD FOR MOLDING CONTAINERS

摘要

A method and system for hydraulic blow molding a container from a preform 24. A molding medium is injected into the preform from a nozzle 12 during a first molding stage. In the first molding stage, the molding medium is injected so as to be specifically directed at a closed end of the preform 24. During the first molding stage, the preform is axially stretched in response to the force exerted on the preform by the molding medium. The molding medium is also injected into the preform during a second molding stage, where the molding medium is injected at a flow rate greater than a flow rate during the first molding stage. During the second molding stage, the preform is radially expanded into the shape of the container.

主权项

1. A method of hydraulic blow molding a container from a preform, the method comprising the steps of:
positioning a preform within a mold having surfaces defining a cavity in the shape of the container; injecting a molding medium into the preform during a first molding stage, the molding medium being a liquid, being injected at a first flow rate and being specifically directed at a closed end of the preform; axially stretching the preform in response to a force exerted on the closed end of the preform by the molding medium during the first molding stage; injecting the molding medium into the preform during a second molding stage, the molding medium being injected at a second flow rate during the second molding stage; and radially expanding the preform into the shape of the container during the second molding stage.