Precipitation hardenable stainless steel was used to cast impact rotors capable of withstanding the corrosion, abrasion and stress inherent in wet corn milling with centrifugal impact machines.
Fifty thousand pounds of steep corn per hour is fed into the rotor, which is rotating at 3600 rpm; the periphery of the 40-inch rotor is traveling over 500 feet per second. Kernels are hurled and smashed against impact posts along the rim of the rotor at velocities approaching that of a fired rifle bullet, according to the manufacturer of the machines, Entoleter, Inc., New Haven, Conn.
Highly corrosive corn steep liquer containing sulfurons acid is freed when the kernels are smashed and thrown from the rotor to impinge on the wall of the machine.
High stresses caused by rapid rotation and centrifugal accelerations of the rotors required design specifications of 100,000 psi tensile strength for the rotors.
The alloy selected for the...