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Foam ceramic filter filtration mechanism

Rectifier: After placing the ceramic foam filter in the casting system, the metal flow resistance increases and the liquid metal changes the flow state in the casting system. The flow can flow slowly into the mold cavity along the casting system, making it difficult to produce eddy currents , So that the liquid metal from turbulence into laminar flow, filling a smooth, play the system slagging function.
Mechanical screening: the presence of large amounts of oxide inclusions, slag and other large impurities in the molten metal. A large number of inclusions can be sieved by mechanical means by selecting a foamed ceramic filter of suitable pore size.
Filter cake mechanism: Foam ceramic filter due to the three-dimensional mesh structure, can be efficient mechanical slag, many are larger than the filter cavity is caught at the entrance of the filter. As the number of trapped inclusions increases, a "filter cake" consisting of large inclusions is formed at the entrance of the filter. The filter cake makes the liquid stream thinner, so that the inclusion of the mesh size is also partially captured in the "filter cake", some can not float the slag can be blocked by the filter. And blocked by the slag itself has a filter function, that is, two-way filter.
Adsorption mechanism: Foam ceramic filter has a large surface area, is conducive to the adsorption of a large number of fine particles. The metal stream is divided into tiny flow units through the filter to increase the area of the metal melt from the filter media. Many of the fine inclusions are adsorbed onto the filter due to gravitational action. This adsorption is mainly based on the choice of non-molecular layer of physical adsorption-based, so that the inclusion of filter in the filter layer by layer until the block so far.
The most commonly used silicon carbide foam ceramic filter, the maximum temperature of 1500 ℃
Foam ceramic filter impact strength is less than straight-through ceramic filter, so choose the same area of the filter, the thickness of the proposed increase of 50 to 75%
80 ~ 90% porosity of the ceramic foam filter so that the metal liquid through a very smooth
Labyrinth channel makes sand and slag more easily blocked
Cast steel filter
Used to cast steel, whether it is through or ceramic foam filter, its physical properties and methods similar to cast iron.
Due to the need for higher casting temperature, mainly the choice of material, must be able to meet the requirements of cast steel.