When sourcing a used rolling mill, you must prioritize the mill type (e.g., 2-Hi, 4-Hi, or 6-Hi) based on your precision requirements. Key technical parameters include the maximum rolling force, roll diameter and face length, and the motor power (kW/HP). It is critical to verify the maximum and minimum entry/exit thickness and the rolling speed (m/min) to ensure it meets your production capacity. Always request the original technical manual and maintenance logs to assess the remaining service life of the bearings and hydraulic systems.