Processing form of graphite material
There are three main types of graphite electrode processing: pressure vibration method, numerical control automatic forming method and mechanical processing method.
(1) Pressurized vibration method: The pressurized vibration method requires a special machine tool, and the electrode master mold and the electrode shape are opposite. The graphite material and the forming tool are relatively placed during processing, leaving a certain gap. A processing fluid mixed with water and abrasive is injected into it. The graphite and the forming tool are subjected to ultrasonic vibration while passing through the processing fluid. Under the impact of the abrasive, the graphite is slightly peeled into the required shape. The abrasive is SiC, B4C or diamond. The coarser the abrasive, the faster the processing speed. When the machine tool is working, it adopts sealed type and water curtain type for processing. Suitable for EDM for mass production.
(2) Numerical control automatic forming method: The numerical control automatic forming method requires a special graphite electrode forming machine, which adopts a numerical control method and has an automatic tool changing device, which can accommodate multiple tools. In order to improve the processing environment, the periphery of the processed graphite electrode is surrounded by a water curtain to prevent graphite dust from being scattered around. In addition, the wet machining method can also be used to prevent the tool from being worn and the graphite dust from being scattered by the water-soluble cutting fluid. The machine tool has a high-performance filtering device that can separate cutting fluid from graphite chips and ensure continuous processing for a long time. It is an ideal special equipment for graphite electrode processing and suitable for mold electrode processing. However, its price is relatively high and its application in the country is not widespread.
(3) Mechanical processing method: The mechanical processing method is the main method adopted by domestic general mold production units.