In order to provide large-size, high-quality and high-quality blanks for the production of high-precision aluminum strips for aluminum processing enterprises, the electrolytic aluminum plant adopts the fully automatic low-level (LHC) combined mold casting technology and uses the electrolytic raw aluminum liquid to directly batch for hot rolling. Aluminum alloy slab ingots can cast 2~5 slabs at the same time.
According to the requirements of alloy chemical composition, after batching with electrolytic raw aluminum liquid, remelting aluminum ingot, returned scrap and intermediate alloy, smelting, degassing and slagging refining, stirring, slagging and sampling analysis are carried out in the smelting furnace. After the composition is qualified, the molten aluminum is transferred to a static furnace, degassing and refining in the furnace, and the temperature is kept standing still, and then the aluminum-titanium-boron wire grain refiner is continuously added to perform online grain refinement. The on-line degassing is carried out by the rotary degassing device, and the CFF two-stage foam ceramic filter device is used to filter and remove the slag. The processed aluminum liquid flows into the crystallizer of the slab casting equipment, and the ingot is produced according to the fully automatic casting process. The flat ingot saw machine cuts the head and tail, and packs them into storage after passing the inspection.
Characteristics of LHC Casting Technology
(1) Compared with the traditional production of slabs with remelted aluminum ingots, it not only saves the remelting process, saves energy, but also reduces metal burnout, reduces environmental pollution, and reduces production. cost.
(2) Using low-liquid level combined mold automatic casting technology, the metal liquid level is much lower than the metal liquid level in the traditional DC casting mold, and the liquid level is between 35-65mm. The crystallizer is lined with a graphite ring on the inner wall of the traditional DC casting crystallizer. The graphite ring adopts continuous penetrating lubrication to smooth the surface of the ingot. LHC casting technology uses two independently controlled cooling water injection devices, which can optimize the process of casting start and stable casting stage. The casting process is automatically controlled by the computer to control the casting process parameters, the production process is stable, and the process parameters fluctuate little.
(3) Low metal level conditions and smooth surface casting of graphite ring, as well as high-efficiency cooling water control, make LHC more compact than the ingot produced by traditional DC casting technology, with smooth surface, thinner coarse-grained layer and segregation zone , To reduce the warpage of the bottom of the ingot. Therefore, the milling amount can be reduced by more than 50%, and the hot rolling trimming can be reduced by more than 15%.