The vicat apparatus shown in figure consists of a frame bearing a movable rod with a cap at end and detachable needle or plunger at the other. The movable rod carries an indicator which moves over a graduated scale having graduations in mm from zero to 40mm on either direction to measure the vertical movement of the plunger. The is attached to the frame.The movable part with alla attachments,I.e.,the cap and rod with needle or plunger,weight 300 gm
The plunger required for determining the consistency, is of polished brass 10 mm in diameter and 50 mm long with the lower end flat and small projection at upper end for insertion into movable rod The needle-A, required for determining the initial setting time,is 1 mm square or 1.13 mm in diameter with the lower end being flat. The needle-B,required determining the final setting time ,is the same as needle-A but with a metal attachment hollowed out so as to leave a circular cutting edge 5 mm in diameter, the end of the needle projection by 0.50 mm. The Vicat mould for cement paste consists of a split ring 80 mm in diameter and 40mm in height and rest on a non-porous palte
The Standard consistency of a cement paste (the amount of water expressed as percent by mass of the dry cement)which permits the Vicat plunger to penetrate to a height 5 to 7 mm from the bottom of the Vicat mould when the cement paste is tested
