Tubular filtration has extremely high filtration accuracy and is mainly used in the production of high-end products, such as high-quality products such as cans, hard disks, aluminum foil blanks, and thin-walled pipes. Tubular filtration is the standard configuration for the production of double zero aluminum foil blanks.
If there is no high-precision and high-stability filtering method in the production of these high-demand products, it may adversely affect the quality of the final product. Therefore, it is a useful attempt to improve the quality of cast-rolled products to try out the tubular filter device in cast-rolling production.
The filter material of the porous tube filter generally adopts the Al2O3-B2O3 series, and the adhesive against molten aluminum is added in a certain proportion to make a tube with voids. Both ends of these loose and porous tubes are fixed by end plates made of silicon nitride or silicon carbide, and a set of several filter tubes are formed.
One or two sets of filter tube groups will be installed in the tubular filter box. Permeation filtration is adopted. The material used for binding particles is from coarse to fine, and the static pressure of aluminum is used to infiltrate from the outer wall of the tube and exit from the tube. End flow, filtration mode is a combination of filter cake mode and depth mode. When the molten aluminum flows through the filter tube set, the suspended slag particles inside the filter tube set are captured and adhered to by the filter channel in the filter tube set, and finally, flow into the outlet cavity of the tubular filter.
The tube filter tube group can also select the particle size of the filter tube according to the product alloy type and unit throughput requirements. The smaller the filter tube particle, the lower the throughput per unit time and the shorter the life, but the higher the filtration accuracy will be.
Tubular filtration mainly has factors such as low flow rate per unit time of casting and rolling, small total throughput using tubular filtration, and high unit material consumption cost. Aluminum foundries generally choose ceramic foam filters to filter aluminum liquid first, because the filter plates are cheap, easy to use, and have better filtering effects.