Some factors will cause the graphite rotors damaged:
1、High temperature oxidation：the main ingredient of graphite is carbon, and it will get visible oxidation at temperatures exceeding 600 ℃, the carbon oxidation reaction is CO and CO2 gases, they can not play a protective role for the graphite rotor; oxidation of graphite rotor is inevitable due to generally degassing tank can not be completely closed; the results of the oxidation of the graphite rotor is its shaft axis diameter progressively becomes smaller, until it breaks scrapped.
2、Molten aluminum erosion: when graphite rotor immersed in liquid aluminum tank, it will rotate at the speed of generally 200r / min ~ 400r / min and strongly agitate molten aluminum, molten aluminum will have a strong erosion、friction to graphite rotor. so at last it will eventually break scrapped.
3、Transmission impact: transmission system of degasser is not stable, damaged will be caused by friction between the rotor and the sealing plug.