... -D21 20Khz Ultrasonic Metal Welding Machine By using the ultrasonic high frequeccy vibration principle, the ultrasonic metal welder converts the ultrasonic vibration energy ... press with the help of punch press ,forging machine or other equipments. 2.Smelting:Mainly aims to ... hardware and tolls, automobile and motorcycle, machine tools, hardware parts and machine parts, hardware mold, etc.4.Welding/ ...