All the blanks for Zhongya slewing bearings are performed by hardening and tempering, hardness can reach HB220-280, the strength is much higher than national standard of GB/T 3077 and GB/T 699, raceway using medium frequency induction hardening machine, hardness can reach HRC55-62, the depth is bigger than 5 mm, inner steel balls are treated by steel ball crushing test to ensure the load of the core.

Zhongya slewing bearings have many advantages: compact structure, light weight, low noise, smooth operation, high precision, safe and reliable, it can bear the axial force, radial force and overturning moment, it doing good on bearing heavy load and low speed.