Process which utilizes specially designed tooling usually vibrating at 15-80 KHz Processes are designed to cause localized heating of thermoplastic materials which, in turn, will provide some type of welded or fused joint Benefits are elimination of fillers and minimized heat stress on surrounding materials
Sound frequencies above audible sound Ultrasonic water and snow level sensors are available that do not make contact with the media of measurement They send out a signal, track the amount of time it takes for the reflected signal to return then use the elapsed time to calculate the distance the signal traveled Air temperature is also measured since the calculation needs to compensate for temperature-related fluctuations in the speed of sound