Cockle cylinder machine generally uses for sepration of broken material. It consists of steel drum into which have thousands of small indents are pressed. It is made in such a shape of indents as to trap only particular size seed. Drum rotates slowly and grain to be graded is feed inside. Paddles are fitted to spread the grains over a wide area. The entrapped grains broken, cockles are separated and discharged by a screw conveyor and machine guarantees total separation of broken grains and cockle.