DEVICE AND METHOD FOR HEAT TREATMENT OF BALLS Russian patent published in 2012 - IPC C21D9/36 

FIELD: metallurgy.

SUBSTANCE: device comprises a quenching bath, a hardening rotor vertically installed inside of it on a drive shaft, with inlet and outlet trays, an elevator connected to the loading tray for equalising the temperature of balls, intermediate trays located behind the elevator, equipped with sprayers for cooling of balls, while the hardening rotor includes an option of regulating frequency of its rotation to determine duration of tempering depending on the temperature of balls at the output. This device implements the method of heat treatment of the balls, which consists in the fact that after stamping or rolling heating the temperature equalisation of balls is performed, then they get cooled with water at a cooling speed not exceeding 12 degrees per second at 150-200°C below the temperature of the end of the rolling or forging, and are subjected to quenching and subsequent tempering.

EFFECT: improved mechanical properties of the grinding balls.

8 cl, 1 dwg