Graphite rotor around at 750 ℃ of aluminum melt in order to speed 200r/min ~ 400r/min the case of continuous work, the general life requirements to achieve more than a month. Carbon Graphite Rotor TM used to produce high-purity graphite, graphite quality of life of the rotor itself has a significant impact, while the surface of the anti-oxidant protective coating service life can be extended to 50-60 days.
Graphite Rotor works
Graphite rotor by the rotor rod, spray two parts. Drive system for rotating the rotor drive graphite, argon gas or nitrogen gas through the rotor pole, blowing nozzle aluminum melt. High-speed rotating graphite rotor to enter the aluminum melt of argon gas or nitrogen gas broke up the formation of many small air bubbles to disperse in the metal solution, while rotating rotor also contributed to the hydrogen within the aluminum melt inclusions proliferation, with those of air bubbles contact with bubbles in the melt by gas partial pressure and surface adsorption theory, the hydrogen absorption of melt, adsorption, oxidation of slag, and with the air bubbles rise, were brought out of the melt surface, so that the melt will be purified.
Graphite main rotor damaged
High-temperature oxidation: Graphite is composed mainly of carbon, graphite in more than 600 ℃ under the conditions of air oxidation of a tangible phenomenon, carbon oxidation reaction product is CO and CO2 gases, the rotor can not be the protective effect; general degassing boxes are can not be completely closed, and most of the inside cavity is not sufficient to protect gas-shielded, graphite rotor oxidation is inevitable. A result of its oxidation of the rotor shaft of the shaft and gradually become smaller, until the break scrapped.
Aluminum liquid scouring: graphite degassing rotor immersed in liquid aluminum box, generally 200r/min ~ 400r/min the speed of rotation and strong stirring of molten aluminum and aluminum liquid on the rotor will have a strong erosion, friction. Particularly in the surface contact area with the rotor pole tapering will eventually break scrapped.
Transmission effects: In addition to gas transmission system is not stable devices, especially in connection with the rotor in different heart operation during the swing rotor, while the friction between the rotor and the sealing plugs causing damage; the other hand, increase the surface of the roll, rotor oxidation, erosion intensified, accelerating the rotor losses.
The use of graphite rotor operating skills
Preheating in advance: graphite rotor immersed in liquid aluminum ago, at about 100mm above the surface at warm-5min ~ 10min, to avoid the quenching effect on the material; rotor must first pass before the immersion fluid into the gas; rotor surface only after the proposed to stop gas supply to prevent the rotor nozzle clogging pores.
Isolated air: indoors pass into the box in the purification of nitrogen or argon gas, to ensure the boxes indoor pressure, isolated from outside air to prevent the oxidation of graphite rotor.
Rotor immersion depth: graphite rotor immersed in molten aluminum a reasonable depth, which strengthen the set of exposed aluminum surface about 80mm, 60mm or so immersed below the liquid level, so that the rotor can effectively increase the antioxidant depletion and erosion wear of time.
Drive smoothly: graphite rotor and the transmission through the connecting rod (tube) to connect to connect a long rod deformed under high temperature, or transmission equipment-related parts loosening occurs, will affect the rotor to the neutral and the smooth operation nature, easy to break or knock produce graphite rotor damage.
Argon gas or nitrogen gas to be pure: If the pipe, joints and other components pass into the aluminum melt leakage caused by argon gas or nitrogen gas is not pure, make the upper part of the serious oxidation of the rotor, even the lower number of rotor fumaroles was oxidized This will considerably shorten the life of the rotor.