Configuration of a 20-mm-diameter 150 kHz ultrasonic longitudinal vibration system for plastic welding

This paper describes 20-mm-diameter 150 kHz vibration systems for ultrasonic plastic welding which were developed. Using 27 kHz to 150 kHz ultrasonic plastic welding systems, temperature rises at welding surfaces of 1.0-mm-thick polypropylene sheets are measured using thermo-couples inserted between sheet specimens and also temperature rise distributions at cross sections of the lapped sheet specimens are measured using a thermo-tracer. The maximum temperature measured was over 240/spl deg/C.