Introduction :

  A mechanical stirring device in which a suitably mounted induction motor will have a vertical shaft having speed of 6000 to 8000 revolutions per minute when loaded. The shaft will be equipped with a replaceable stirring paddle of either of the types and made of metal. The surface will be of such length that the stirring paddle will operate not less than 20 mm and not more than 35 mm above the bottom of the dispersion cup. The dispersion cup will be supported on a rest and shall have a removable baffle. A special dispersion cup conforming to either of the designs shown in IS 2720 (Part IV) 1985 will be provided to hold the sample while it is dispersed. The stirrer will be free from vibration whilst operation and the base will be made of M.S. of at least size 20 cm X 25 cm with rubber cushions. The container and baffle will be of such material as not be affected by the reagents like sodium Carbonate, Sodium silicate , Sodium Hexametaphosphate etc. The stirrings device will be suitable for operation on 230-250 Volts A C with controller switch for different revolution. It will be provided with 3 core wiring of with off-on switch on side. The dimensions of stirring paddles for stirring apparatus and dispersion cup will be as per IS 2720(Part IV)1985.