Ultrasonic Cleaner Safety Tips: What to Avoid Before You Start Cleaning

An ultrasonic cleaner is easy to use, but it should not be treated like an ordinary water tank. The machine uses ultrasonic vibration, heating, electrical components, and cleaning solution at the same time. If it is used incorrectly, cleaning performance may become poor, and the ultrasonic cleaning tank, transducers, or parts being cleaned may be damaged.

You may have learned how to use a sonicator bath and how to use a digital ultrasonic cleaner, but that’s not enough. This guide will explain the most important ultrasonic cleaner safety tips for daily use, especially for stainless steel ultrasonic baths and industrial ultrasonic cleaners.

Do not turn on the ultrasonic function when the tank is empty. Ultrasonic transducers are designed to work through liquid. Running the machine dry may cause overheating, abnormal vibration, and possible damage to the transducers or generator.

Before starting, always check that the liquid level is above the minimum working level. If you use a basket or tray, make sure the parts are fully covered by the cleaning solution.

Parts should not be placed directly on the bottom of the ultrasonic tank. Direct contact can block ultrasonic energy, reduce cleaning efficiency, scratch the stainless steel tank, and increase stress on the transducers.

Use a stainless steel basket, perforated tray, or suitable fixture. A basket allows the cleaning liquid and ultrasonic energy to move around the parts more evenly.

Especially for heavy industrial parts, use a stronger basket or custom support frame. The part should be held securely without pressing directly against the tank bottom.

Water alone can transmit ultrasonic energy, but it may not remove oil, grease, carbon, polishing compound, or other contaminants effectively. A suitable ultrasonic cleaning solution usually improves the cleaning result.

Choose the solution according to:

• Part material
• Type of contamination
• Required cleaning result
• Temperature range
• Corrosion sensitivity

Avoid using random chemicals just because they seem strong. The wrong solution can damage the part, the basket, or the stainless steel tank.

Do not use flammable solvents in a standard ultrasonic cleaner. Ultrasonic vibration and heating can increase vapor formation, and solvent vapor may create a fire or explosion risk.

For most cleaning work, use water-based ultrasonic cleaning solutions. If your process requires a special solvent, the equipment and operating environment must be designed for that purpose.

Most ultrasonic cleaner tanks are made of stainless steel, commonly SUS304. Stainless steel has good corrosion resistance, but it is not suitable for every chemical.

Strong acid, bleach, chloride-rich solutions, or aggressive chemicals may corrode the tank, damage welds, or shorten the machine’s service life.

If you must clean with acidic or special chemical solutions, ask the supplier first. For some industrial applications, a different tank material or special process design may be required.

Fresh liquid contains dissolved air. Too much air in the solution can weaken cavitation and reduce cleaning performance.

After adding a new solution, run the ultrasonic cleaner for several minutes without parts, or use the degas function if the machine has one. Once the solution is degassed, the ultrasonic cleaning effect becomes more stable.

This step is especially useful for precision cleaning, laboratory cleaning, and first-time use after changing the solution.

Cleaning solution becomes less effective after repeated use. Oil, metal particles, dust, and loosened contamination can remain in the liquid or settle at the tank bottom.

A dirty solution may cause poor cleaning results and may redeposit contamination on parts. For better performance, replace or filter the solution regularly.

For industrial parts with heavy oil, a filtration system can help extend solution life and reduce manual cleaning work.

Heating can improve ultrasonic cleaning, especially for oil, grease, wax, and some residues. However, higher temperatures are not always better.

Too much heat may affect plastics, rubber, coatings, adhesives, or precision components. It may also cause some chemicals to evaporate faster.

Before cleaning sensitive parts, check the recommended temperature for both the material and the cleaning solution.

If too many parts are placed in the basket, ultrasonic energy may not reach every surface evenly. Parts may block each other, and cleaning time may become longer.

Leave enough space between parts. For parts with holes, grooves, or blind areas, adjust the placement so the cleaning solution can enter and drain easily.

For batch cleaning, it is usually better to clean fewer parts properly than to overload the tank and get inconsistent results.

Ultrasonic cleaning is effective, but some items are not suitable for strong ultrasonic action. Delicate coatings, soft metals, painted surfaces, glued parts, porous stones, and sensitive electronic components may require special care.

Before cleaning a valuable or delicate item, test one piece first. Use lower power, shorter time, lower temperature, or a higher frequency machine if needed.

Different cleaning jobs need different ultrasonic settings.

Lower frequencies, such as 28kHz, create stronger cavitation and are suitable for durable metal parts with heavy contamination. 40kHz is commonly used for general cleaning. Higher frequencies, such as 60kHz, 80kHz, or above, are better for precision cleaning and delicate surfaces.

If your ultrasonic cleaner has adjustable power, start with a lower setting for sensitive parts and increase only when needed.

After ultrasonic cleaning, residue from the cleaning solution may remain on the part surface. Rinse the parts with clean water or another suitable rinse liquid when required.

Drying is also important, especially for metal parts that may rust or parts with small holes where water can remain.

Before starting your ultrasonic cleaner, check these points:

• The tank has enough liquid
• Parts are placed in a basket, not on the tank bottom
• The cleaning solution is suitable for the material
• No flammable solvent is used
• Fresh solution has been degassed
• The temperature is suitable for the parts
• The basket is not overloaded
• Delicate parts have been tested first
• The dirty solution is replaced or filtered
• Parts are rinsed and dried after cleaning

An ultrasonic cleaner can provide excellent cleaning results when it is used correctly. The most important rules are simple: never run it dry, never place parts directly on the tank bottom, use the correct cleaning solution, avoid unsafe chemicals, and match the cleaning settings to the part material.

For benchtop ultrasonic cleaners, industrial ultrasonic cleaning tanks, or customized cleaning applications, Anonkia can help recommend the right tank size, frequency, power, heating, basket, and cleaning process according to your parts.