Ceramic foam filters will always encounter various problems in use in terms of initial pressure, operating temperature, the cross-section of runners, tightness, filtration accuracy, and filtration flow. In this article, we will introduce the filtration accuracy and filtration flow in the use of foam ceramic filters.
The finer and thicker the pore size of the filter, the higher the filtering accuracy. However, the problem of plugging holes is prone to occur, and the cost of filtration is higher. In some cases, a larger pore-size fiber filter can be selected for use.
Filtration Flow of Foam Filters
Filtration flow is proportional to the porosity of the filter. With filter filtration, the large particles in the metal melt have a blocking effect on the fine pores of the filter and do not wet the surface tension of the large particles. It will reduce the melt flow and cause plug holes in severe cases.
The amount of liquid metal that any filter can filter per unit area is certain. Therefore, when selecting a filter, the most reasonable size should be calculated according to the weight of the ladle, pouring time, etc., so as to avoid high cost or incomplete pouring in the middle.
The cost issue is the first consideration in the production process of each product. From other considerations, it can be found that the weight of the initial pressure head involves the selection of the strength of the filter, the control of the initial casting temperature, the size correction caused by the placement of the filter in the sprue, the problems caused by poor sealing, and the damage caused by insufficient consideration of the initial clearance. , the selection of hole density and size, etc., there is a risk of increasing the cost of castings if you are not careful.
Therefore, attention should be paid to the selection of filter size specifications, the rationality of the design of the pouring system, the standardization of the pouring process operation, and the comprehensiveness of the problems considered in the early stage.