Welding - schools, laser, resistance…

Ultrasonic welding machines’ quick, clean process uses high-frequency vibrations and pressure instead of heat to melt and weld plastics, which provides many benefits.

Ultrasonic welding, perhaps the most rapidly developing field in the industry, uses high-frequency vibrations - not heat - to weld plastic pieces together. Ultrasonic welding machines are used to join small- and medium-sized pieces of plastic by creating frictional heat that melts the plastic together. Once the vibrations stop, the plastic immediately cools and solidifies.

There are many benefits of electronic welding, including that the process is quick and repeatable. Further, the process does not “consume” any additional materials, which means it does not require screws, nails, bolts, soldering materials, glues or other adhesives. Ultrasonic welding machines may even be used to create hermetic seals, because the finished pieces are so strong and clean. An added benefit is that no ventilation system is required because no heating is involved.

Through pressure and high-frequency mechanical vibrations (15 kHz to 40 kHz), the plastic is quickly melted into a solid-state weld. Many ultrasonic welders run at 15 kHz, 20 kHz, 30 kHz and 40 kHz frequencies.

The ultrasonic process begins with two thermoplastic pieces that have similar melting points. They are placed together, one atop the other, in the ultrasonic welding machine. Then, high-frequency vibrations are applied directly to the joint being welded. With the vibration application concentrated in the joint itself, the process melts the joint but not the base materials. When the plastic melts, the vibration is stopped and pressure is applied - and the plastics are melded. Because the process is as fast and efficient as it is, weld times are sometimes less than a second.

The ultrasonic welding process has become invaluable to many industries. They include the automotive, cosmetic, computer, appliance, toy, medical, electronics, textile, packaging and food industries. Ultrasonic welding is usually preferred in the medical-supply industry, because the no parts are contaminated by outside materials. Products processed with ultrasonic welding machines can even be used for “clean rooms” in hospitals. One of the most typical uses of ultrasonic welding is in the packaging and food industries, which also count on the contaminant-free, clean, quick process.

Ultrasonic welding has come a long way and is now one of the most progressive industrial techniques. It was in the late 1940s that ultrasonic waves were first used - mostly for cleaning. Then, in the 1950s, ultrasonic welding was introduced as a way to weld plastics and metals. In 1965, the patent for the process was granted to two men - Robert Soloff and Seymour Linsley. The popularity of ultrasonic welding began with the toy industry and has spread to a growing number of applications every year.

Now, some 60 years after its advent, ultrasonic welding has emerged as the leading assembly method for rigid thermoplastics. Ultrasonic welding machines come in many models, including ultrasonic hand guns; bench-top integrated ultrasonic welders; automation ultrasonic actuator heads and modular power supplies; and closed-loop process controls, like energy welding, distance welding, time welding, force welding, automatic frequency tuning and variable-amplitude output control. Microprocessor and standard-time models are available, as are tools of the trade, like ultrasonic horns, fixtures, converters and boosters for all makes, models and brands of ultrasonic welders.

When it comes to companies that provide plastic assembly solutions, look for top-notch service and technical support and a company that meets each customer’s individual needs. For superior ultrasonic welding machines, check out Plastic Assembly Systems at www.heatstaking.com.

Source: Internet