METHOD OF AND SYSTEM FOR CONTROLLING FLOW OF MOLTEN LIQUID TO CAST METAL ALLOYS

摘要

In the casting of metal alloys with low melting temperatures, an improved control system for lowering an injection piston in an injection cylinder is provided to avoid porosity occurring in castings. There is a fluid operated drive cylinder with a drive piston connected to the injection piston. A transducer is linked to the injection piston to provide an indication of location, and a controller compares the position of the injection piston with a predetermined time/distance profile and produces an injection stroke signal which is used to control the drive cylinder and ensure the injection piston follows the time/distance profile.