HAD A STARVE ON CKD FEEDER ON FINISH MILL #4. EMPLOYEE WENT DOWN TO BEAT ON CONE OF SILO TO GET MATERIAL TO FLOW. AS HE BEAT ON THE SILO CONE A 4"" PIPE CAP CAME OFF THE ACCESS PORT ON THE SIDE OF THE CONE. THE CKD CONE CAME OUT AND GOT IN EE'S LEFT EYE.