Ceramic foam filter plate is the last technology to purify aluminum melt. The selection of ceramic foam filter plates is particularly important. According to the environment of each foundry, the best filter plate is selected for filtration, so as to obtain a clean aluminum melt. In order to prevent the aluminum melt from leaving the filter box, it will cause secondary pollution during the solidification process. Long service life, high strength, non-stick aluminum and good thermal insulation launder, front box, distribution plate and hot top casting cap, so as to ensure the cleanliness of the aluminum melt.
The selection of foam ceramic filter plate depends on the impurity content in the molten aluminum, the flow rate of melt injection and the quality requirement of the casting products.
There are many impurities and the quality of casting products is general. A large foam ceramic filter board with large holes and holes can be selected. At this time, it is important to filter the semi-continuous casting with glass fiber cloth first. It can intercept the slag from the opening and the slag washed down by the launder to prevent the blocking of the filter plate.
The quality requirements of casting products are high, and a new type of foam ceramic filter is selected with small holes and large mesh sizes. The most prominent is the selection of 30ppi and 60ppi two-stage filtration technology to achieve ideal cleanliness and good results.
The selection of filter plate specification is determined by the flow rate and total flow rate of melt. If the flow rate is large, the total throughput is large, and the hole size of the filter plate is small, the larger specification is selected.
When selecting ceramic foam filters, the effective surface area or porosity of the foam should be carefully assessed. The mesh homogeneity of the surface layer of the filter plate can be observed, and then the mesh homogeneity of the section can be observed by cutting. If the conditions are available, the porosity can be measured and calculated by the drainage method. The three-dimensional mesh is homogeneous and the porosity is relatively large, which is an excellent foam ceramic filter plate.