Martin Frost – UK sales manager, Telsonic UK the wholly owned subsidiary of Telsonic AG Switzerland, talks to AZoM about the ultrasonic torsional welding. In plastic welding, conventional LINEAR ultrasonic welding heads are arranged vertically and use a converter, operating at between 20kHz and 40kHz together with a booster, to increase the amplitude. The sonotrode or horn is in turn coupled to the booster, which utilises the change in cross sectional area of the sonotrode to magnify this amplitude at the working face. This configuration of components is known as the Ultrasonic stack. By using a pneumatic actuator in conjunction with the energy being delivered via the sonotrode, the process creates local heat and melt through ultrasonic agitation of the polymer molecules. The pressure from the pneumatic actuator force collapses the molten joint feature and holds it in position until the weld joint has solidified. When used in metal welding (usually non ferrous metals) LINEAR ultrasonic welding operates in the horizontal plane with the ultrasonic stack in the horizontal mode. This oscillates the top part of the welded assembly about the bottom part as a friction weld. This causes...