... and save labour YP-D21 20Khz Ultrasonic Metal Welding Machine By using the ultrasonic high frequeccy vibration principle, the ... certain temperature into other shapes through forging press with the help of punch press ,forging machine or other equipments. 2.Smelting ... various hardware and tolls, automobile and motorcycle, machine tools, hardware parts and machine parts, hardware mold, etc.4.Welding/ ...