Ultrasonic cleaning efficiency depends on the parameters of the sound field (vibration frequency and sound intensity) as well as physico-chemical properties of the liquid detergent. Selecting the sound field parameters and the washing liquid properly can grant the required cleaning efficiency. Much depends on the quality of the equipment itself: if you are looking for high quality ultrasonic cleaner offering decent functionality, drop in at hilsonic.co.uk – a reliable UK manufacturer, boasting an impressive line-up of powerful ultrasonic cleaners at affordable prices.
In the cleaning process the surface tension of the washing liquid also matters, degrading wetting process parts to be cleaned and preventing the penetration of the detergent solution into the gaps. To reduce the surface tension of the washing liquid additives surfactants are used which improve the wettability and the surface, creating a subtle adsorption layers on the particle surface contamination and promoting their detachment easier.
Introduction of ultrasonic vibrations is carried out through the plates, which have a good acoustic contact with the transducer. The geometrical dimensions of the plates are determined on the basis of the conditions for obtaining the required intensity of the ultrasonic vibrations, while the optimum value is selected depending on the nature and type of contamination of parts.
Decontamination, degreasing and cleaning in the focus
The main types of contaminants that are removed in the process of ultrasonic cleaning can be grouped into four categories:
- Solid and liquid films – different oils, greases, pastes, etc.;
- Solid precipitation – metal and abrasive particles, dust, deposits, water-insoluble inorganic compound (scum, flux), and soluble or partially soluble organic compound (salt, sugar, starch, protein, etc.);
- Сorrosion products – rust, scale, etc.
- Preservatives, preservative and protective coatings – enamels, resins, etc.
The correct choice of washing medium is the main and decisive factor in the quality and time ultrasonic cleaning. As the medium for ultrasonic washing using various cleaning solutions and solvents.
Taking advantage of using organic solvents (benzene B-70, Freon-113, carbon tetrachloride, trichlorethylene, acetone, dichloroethane, etc.) is justified for purifying the surfaces from polishing pastes, oils (mineral, vegetable, and animal), petrolatum, paraffin and tar. They do not cause corrosion of metal, having a small surface tension, readily penetrate into cracks and holes and dissolve therein dirt.
Wide application for ultrasonic cleaning is found in the face of freon. This is due to its high solubility, low toxicity, non-flammability and the possibility of easy recovery. Ultrasonic cleaning can also be conducted in various alkaline solutions. They are used for degreasing parts, cleaning of grease, polishing pastes, metal dusts, abrasives etc.
In order to achieve the desired mode of ultrasonic cleaning a selection of the optimal value of the oscillation frequency also has an absolutely crucial role. Most ultrasonic cleaning units operating in the frequency range from 18 to 44 kHz. Structurally, the ultrasonic units consist of a generator of appropriate power and baths of different working volumes. At the bottom of the bath mounted piezoceramic transducers that are acoustically connected to the bottom of the bath.