Method for material recovery in electroerosion machining

A rough machining method for long aspiration hole drilling, the method comprising:

• providing an electrode assembly comprising:
• a pipe-shaped electrode body defining a hollow interior, the pipe-shaped electrode body having a working end positionable adjacent a workpiece to be rough machined;
• and
• one or more replaceable inserts affixed to the electrode body at the working end;
• energizing one of the workpiece and the electrode assembly as an anode and energizing the other of the workpiece and the electrode assembly as a cathode;
• advancing the electrode assembly into the workpiece so as to generate a hole, with a core of workpiece material being formed within the hollow interior of the pipe-shaped electrode body as the electrode assembly advances into the workpiece;
• directing a protective gas toward the working end of the pipe-shaped electrode body;
• pumping an electrolyte from an electrolyte supply down through a working gap between the working end of the pipe-shaped electrode body and the workpiece as the electrode assembly advances into the workpiece;
• channeling the electrolyte and workpiece debris resulting from the removal of workpiece material through flushing channels on an outer surface of the electrode body to transfer the workpiece debris away from the cutting surface of the electrode body, the flushing channels being defined by a plurality of flutes formed on the outer surface of the electrode body;
• recycling the core of workpiece material once the core is separated from a remainder of the workpiece, upon advancement of the electrode assembly through an entirety of the workpiece, with the protective gas preventing oxidation of the core of workpiece material and enabling recycling thereof;
• wherein directing the protective gas comprises channeling the protective gas down through a gas channel formed between the pipe-shaped electrode body and a shield member positioned about at least a portion of the electrode body and spaced apart therefrom, with the shield member not extending all the way down to the working end of the pipe-shaped electrode body.

A method of manufacturing an electroerosion machining system comprising:

• providing an electrode assembly configured to machine a desired configuration in a workpiece;
• providing a power supply configured to energize the electrode assembly and the workpiece to opposite electrical polarities;
• and
• providing a working apparatus configured to move the electrode assembly relative to the workpiece;
• wherein providing the electrode assembly comprises:
• providing a pipe-shaped electrode body defining a hollow interior sized to accommodate a core of workpiece material therein resulting from a hole drilling of the workpiece;
• and
• attaching one or more replaceable inserts to the pipe-shaped electrode body at a working end thereof, the one or more replaceable inserts constructed so as to be selectively attachable and detachable from a working end of the pipe-shaped electrode body at locations about an outer circumference of the electrode body;
• and
• wherein providing the electrode assembly further comprises:
• forming a plurality of flutes formed on an outer surface of the electrode body, the plurality of flutes forming flushing channels to direct a cutting fluid and workpiece debris away from the working end of the pipe-shaped electrode body;
• and
• positioning a shield member about a portion of the pipe-shaped electrode body, the shield member being spaced apart from the pipe-shaped electrode body to define a gas channel through which a protective gas may be provided down to the working end of the electrode body, so as to prevent oxidation of the core of workpiece material and provide for recycling of the core;
• wherein the shield member does not extend all the way down to the working end of the pipe-shaped electrode body.