In a typical automotive filtration application, laminar flow occurs, so the technique of applying lognormal pore distribution can be considered. A more important structure is that the loose paper sheet not only has a larger number of fine pores than the compact paper sheet, but also The wide range of hole sizes makes it impossible to use conventional papermaking methods to produce sheets with a large number of uniform apertures. In the case of a background with an organic liquid having a certain pressure head, air is allowed to flow through the sheet in a pressurized state, and the distribution of fine pores can be obtained by analyzing the air flow condition. Unfortunately, it is not yet possible to establish a correlation between the measured pore distribution and the particle removal efficiency of filter paper. The main reason is the complexity of the mechanism by which the particles are removed when the liquid flows through the filter medium, that is to say, this is not A simple filtering process, in fact, inferring anything about filtering performance based on the pore size value is dangerous. Therefore, the current design of automotive filter paper is mainly based on accumulated experience and new ideas provided by the paper structure analysis, rather than the unquestionable reality based on the filtering behavior. The filter paper has a positive asymmetry which can be easily seen. The upper surface of the filter paper is loose and has a high permeability. The filter paper gradually becomes densely downward and has low permeability. The filtration performance of the filter paper is obviously determined by which surface of the filter paper is the upstream side during filtration. Therefore, the filter paper producer should mark the lower surface of the filter paper (usually the color line) so that the filter manufacturer can easily recognize it and use the upper surface as the upstream side. Fag Mixer Bearing,Fag Spherical Roller Bearings,Concrete Mixer Truck Bearing,11449 Concrete Mixer Truck Bearing Jinan Bosch Bearing Co.,Ltd , https://www.bosch-bearing.com