What is Ultrasonic Cleaning?
Ultrasonic cleaning is a high-quality cleaning technique. It uses ultrasound combined with a fluid to clean the surface in contact. The high-frequency sound waves agitate the liquid, creating a scrub effect. Sound waves, typically 40kHz, cause the liquid to cavitate.
Cavitation can be thought of as bubbles. When ultrasonic sound waves pass through the liquid, they create these cavities of energy or bubbles in the liquid. These bubbles implode when in contact with the surface to be cleaned. The implosion of these bubbles is what cleans the surface.
The cleaning can last from 6 to 20 minutes, depending on the object that is to be cleaned.
Sometimes the ultrasound can be used with just water. Aqueous solutions are widely used, such as surfactants, detergents, and alkaline and acid cleaners. One thing to be careful about is that the cleaning fluid must not attack the cleaning equipment and should not foam much as well.
What are ultrasonic cleaners used to clean?
Ultrasonic cleaners are used with many different objects. They are used with jewellery, scientific samples, optical parts, dental and surgical instruments, coins, tools, fountain pens, car fuel injectors, firearms, musical instruments, gramophone records, electronic equipment, etc.
The ultrasonic cleaning equipment is mostly used in jewellery workshops, by watchmakers, in scientific labs and electronic repair workshops, and even in the aerospace industry.
How does the Ultrasonic Cleaning system work?
The ultrasonic cleaning system works using three basic components. It has a tank that holds the cleaning fluid and items to be cleaned. There is an ultrasonic generator that uses an alternating current to generate an ultrasonic signal. The ultrasonic transducer then converts the ultrasonic signal to mechanical energy.
Ultrasonic Cleaning Tank?
The tank is the simplest component of an ultrasonic cleaning system. It is simply used to hold the cleaning liquid and the object to be cleaned.
What is an ultrasonic generator?
An ultrasonic generator converts the AC electrical energy to electrical energy appropriate for energizing a transducer to produce ultrasonic frequency waves. It is basically a power supply that takes input from a wall outlet and transforms it to the appropriate energy level. It sends high voltage pulses to a transducer.
Most ultrasonic cleaning systems use a frequency of 40kHz, but in some cases, a lower or a higher frequency can be more effective. This depends on the material to be cleaned. Larger and heavy items require low-frequency waves as this yields bigger and stronger cleaning bubbles at a slow speed. While small and delicate items require less strong bubbles but a faster rate thus, higher frequency waves are required. The frequency can vary from 20kHz to 200kHz.
What is an ultrasonic transducer?
The ultrasonic transducer is the most important part of an ultrasonic cleaning system. This is the part that uses the power from the generator and produces sound in the ultrasonic zone.
It has 3 basic components, an active element, a backing, and a radiating plate. Mostly the ultrasonic cleaners have piezoelectric crystals as the active element. This crystal uses the piezoelectric effect to change the electrical energy to ultrasonic energy. The piezoelectric effect is where the crystal changes size and shape when it receives electrical energy.
The backing is used to absorb energy radiated from the crystal.
The radiating plate converts the ultrasonic energy to mechanical energy (pressure). It is like a diaphragm.
Ultrasonic Generator and Immersible Ultrasonic Transducer:
Ultrasonic Cleaning System Equipment
The simplest is the tank. They come in various shapes and sizes, from small tabletop tanks to large industrial scale tanks with a capacity of hundreds of gallons.
The whole cleaning systems come with a multi-tank configuration as well.
For greater accuracy and to save time, the cleaning systems with automated technology are also there. This not only saves time but also reduces human effort. It is like a dishwasher.
One thing to be careful about is to not use flammable fluids. This is because the ultrasonic waves heat the liquid. Also, try not to contact the liquid when the system is running, as the heat can irritate and burn the skin.