In the industrial purification process, the most advanced treatment method in the world is to mix the purification gas and solvent and use the rotation of the graphite rotor to inject them into the aluminum melt for purification treatment. Then, damage is inevitable in the process of using the graphite rotor, so Xiaobian will teach you how to take measures from the causes of damage to make the life of the graphite rotor longer.
The first cause of damage is high-temperature oxidation: the graphite is mainly composed of carbon. The graphite will undergo visible oxidation under the air condition of more than 600 ℃. The products of carbon oxidation reaction are CO and CO2 gas, which can not protect the rotor; Generally speaking, the degassing box can not be completely sealed, and most of the box cavities are not filled with protective gas, so the oxidation of graphite rotor is inevitable. As a result of its oxidationGraphite rotorThe shaft diameter gradually decreases until it is broken and scrapped.
Corresponding protection measures: anti oxidation coating rotor, effectively slowing down the oxidation process of the rotor and extending the service life of the rotor
The second cause of damage is liquid aluminum scouring: the graphite rotor is immersed in the liquid aluminum in the degassing box. Generally, it rotates at the speed of 200R / min ~ 400R / min and strongly agitates the liquid aluminum. The liquid aluminum will cause strong scouring and friction to the rotor. In particular, the contact part between the liquid level and the rotor rod will gradually become thinner, and finally it will be broken and scrapped.
Corresponding protection measures: anti oxidation coating rotor, high-quality graphite raw material, high strength and erosion resistance
The second cause of damage is the influence of the transmission system: the transmission system of the degassing device is unstable, especially the connection with the rotor is not concentric, and the rotor swings during operation. On the one hand, the friction between the rotor and the sealing plug causes damage; On the other hand, the tumbling of the liquid surface is increased,Graphite rotorOxidation and scouring are intensified, which accelerates the loss of the rotor.
Corresponding protection measures: oxidation resistant coating rotor, precise CNC processing, high coaxiality.
