... Convenient and save labour YP-D21 20Khz Ultrasonic Metal Welding Machine By using the ultrasonic high frequeccy vibration principle, the ... forging press with the help of punch press ,forging machine or other equipments. 2.Smelting:Mainly aims to melt ... for various hardware and tolls, automobile and motorcycle, machine tools, hardware parts and machine parts, hardware mold, etc.4.Welding/Brazing:It ...