The apparatus is used for determining the fineness of Portland Cement measures the specific surface area of fine materials in square centimeters per gram of test sample. By using this apparatus, a quantity of air is drawn through a bed of definite porosity. The rate of airflow is determined by the pore volume in the bed, a function of the size of particles.
The apparatus consists one each of permeability cell 12.5mm I.D. manometer ‘U’ type mounted on stand with a built-in stop cock, perforated disc, plunger rubber stopper, rubber tube 30cm long. Packet of 12 filter paper disc and a bottle of 100ml dibutyl phthalate liquid.