Ultrasonic Welding of Polymer Material

Shield Ultrasonic is committed to continuous and vigorous research of ultrasonic welding processes: we constantly add new materials to our list of weldable elements. If you are looking for the best ultrasonic welding equipment, do not hesitate to contact us; send us your test specimens and see for yourself the welding quality and speed we are able to offer. Weld materials do not have to have the same composition to be welded. For example, these materials can be welded together using ultrasonic technology: cardboard paper and plastic (Tetra Pak), metals and non-metals, different polymer materials such as ABS plastics, polyamide, polystyrene, spunbond, etc. Before a new welding machine is put into production, we model future welding processes and study the properties of new materials to achieve optimal performance and to provide equipment that will last our users well into the foreseeable future.

Ultrasonic welding is increasingly being used for challenging applications such as connecting elements and components to manufacture items out of different plastics and nonwoven fabrics, because it ensures a durable connection in a quick and easy manner. Unlike conventional welding, ultrasonic welding of polymers provides a stronger bond between welded materials without cumbersome pre-weld surface preparation and post-weld dressing. Moreover, there are no internal stresses in the weld zone and in many cases the weld is not visible at all.

Ultrasonic welding may either be seam welding (continuous or stitch welding) or contour welding (closed/unclosed). Shield Ultrasonic develops and produces powerful (up to 3 kW), high efficiency piezoceramic radiators and generators designed specifically for ultrasonic welding machines to minimize ultrasonic pulse length and guarantee high welding quality. For example, when spunbond is welded, the ultrasonic pulse length for a weld 300 mm long and 3 mm wide is only 0.01 s (10 ms).

Based on these radiators, Shield Ultrasonic develops and produces customized ultrasonic welding machines for polymers such as spunbond, polystyrene, polyamide, polyethylene, polyvinyl chloride (PVC) and more, tailored to the customer's process in order to offer the best efficiency and value.

Welding is a process that creates a permanent connection between the atoms of welded elements. Metals are welded by heating and fusing, i.e. mixing metal molecules in contact areas. Ultrasonic welding is used to weld polymer materials without high temperature exposure. During ultrasonic welding materials are exposed to microdeformations, friction, heating, dispersion, and diffusion induced by high-frequency mechanical microvibrations (18 to 100 kHz).

A durable connection is made in the ultrasonic environment and under a certain pressure in the welding area. When ultrasonic settings of a welding machine, e.g. vibration frequency, power consumption, and pressure, are correct and match those required for the specified material, welding speed may be as high as fractions of a second, including weld cooling/hardening time. Ultrasonic welding is classified by the type of welding machines: spot welding, contour press welding, seam welding, spot-and-seam welding machines and portable instruments such as low-power stick guns. Power consumption is 100 to 2,000 kW.

For more details please contact us at:

805 375-0061