When evaluating a tin can flattening machine, you must prioritize processing capacity (kg/h or units/h) to ensure it meets your production volume. Key technical factors include the motor power (typically 2.2kW to 7.5kW), the roller material (look for hardened alloy steel or 45# carbon steel for durability), and the adjustable gap range which determines the final thickness of the flattened cans. Additionally, ensure the machine features an automatic feeding system to increase efficiency and reduce manual labor risks.