Ultrasonic Transducers

Ultrasonic transducers are used for a variety of purposes such as flaw detection, thickness gauging, material research & medical diagnostics, biomedical applications, non-destructive application evaluations, penetration of thick materials. The basic mechanism used in these devices involves the transformation of sound energy into electrical energy and vice versa.

The sound frequency used in these is usually in the range of one hundred kilohertz to fifty megahertz which is way above the normal human hearing range of twenty thousand hertz. The sound generated at these frequencies has a shorter wavelength that can reflect small surfaces and enable it to detect the defects inside solid materials such as metal and plastic.

These devices use Piezo or ferroelectric material as an active element to detect flaws by converting the excitation pulse (electrical energy) generated from the flaw detector into ultrasonic energy. The transducer's performance is enhanced with the use of materials such as Piezo polymers and composites that are capable of producing different wave modes, by cutting the ceramics in different forms. These devices contain a backing component made from high-density material to absorb the energy radiated from the active element's back face, and control the vibration of the transducer. They also contain a wear plate made from corrosion-resistant material such as steel in order to protect the transducer element from the environment of testing.

The operations of these devices are based on the principles of piezoelectric effect or magneto restrictive effect for producing ultrasonic sound. Ultrasonic frequencies used in these devices are produced by combining the output of an electronic oscillator to a thin wafer or piezoelectric material like lead zirconate titanate.

Ultrasonic transducers are better than electronic sensors as they can be used in measuring and detecting object distances and detecting small objects from a long distance. They are also resistant to dust, dirt, moisture, and are not affected by external disturbances such as vibration, infrared radiation, ambient noise, and EMI radiation.

A standard flowmeter either uses a float or a paddlewheel to measure flow. In order to work, fluid is passed through the flowmeter which either spins the paddlewheel or pushes afloat. For installation either you cut into the pipe to attach the flowmeter or you have a branch off to use a floater flowmeter.

The ultrasonic flowmeter is different. This flowmeter will work with any sound conducting liquid. The ultrasonic flow meter is placed near the application and two clamp-on "transducers" are placed on either side of the pipe. To detect flow through a pipe, ultrasonic flowmeters use acoustic waves or vibrations of a frequency. Depending on the design there are two ways of measuring flow, either Doppler or Time-transit.

There is No moving parts and less chance of breaking down. No paddle wheels or floats to break and replace. No wetted materials, nothing touches the liquid it's measuring. Ultra Sonic Flowmeters work with clean and dirty fluids. Since the flowmeter measures with sound frequencies, the liquids can have solids and still keep an accurate measure of flow. The ultasonic flowmeter is best suited for corruptible liquids that eat away plastics. For example sewage, slush and beverages, where the standard flowmeter just can not cut it. It's the perfect flow meter.