132# upper tool weight, 54” x 22” lift table, 23.5″ daylight, 35 KW Lenze drive, Allen Bradley SLC5/04 PLC, Panelview 1000 HMI, low cycle count, 2002
Vibration welding uses motion and pressure to friction weld thermoplastic part halves. Lower parts are lifted into contact with upper parts, which hang from springs and vibrate controllably between magnets rigidly attached to the machine frame. Frequency at which upper tools vibrate is determined by their weight and mass. Each tool needs to be tuned. A DC power supply (inverter) controls the frequency and amplitude (distance) at which the springs vibrate. Once part halves melt at the contact area, clamping pressure forces them together, creating strong welds, once joints cool and re-solidify. Small and medium sized parts (6″ – 48″ long) are rubbed quickly, using high frequencies. Large parts (60 – 120″ long) are rubbed more slowly. Vibration welding is relatively fast (5 – 30 second cycles), making it suitable for production.