The sound may not be the norm when cleaning in your home, but it is just the thing for cleaning delicate jewelry, surgical instruments, lenses, and many other small, intricate objects. Soon, it could also make cleaning big objects like houses or machines much more efficient.
The cleaning method of using high-frequency sound to clean is known as ultrasonic cleaning.It is often used to get rid of the dust, dirt, oils, and other particles clinging to small objects. The term ultrasonic means that the frequency of the sound waves used in this technique is higher than what a human can hear.
Ultrasonic cleaners usually involve frequencies between 20,000 Hz and 40,000 Hz, but sometimes they are even higher. Hence, a human hearing ability varies from the range of 20 Hz to 20,000 Hz. For comparison, dogs can hear noises in the range of 40 Hz to 60,000 Hz, and bats can hear noises in the range of 20 Hz to 120,000 Hz.
Ultrasonic cleaners come in many types, from home models that cost less than $50 to industrial-grade models that sell for thousands, but the underlying theory is the same.
How Does This Cleaning Method Work?
In an ultrasonic cleaner, a wave generator is connected to a diaphragm, I.e. the cone-shaped part that vibrates inside of a speaker. The generator causes the diaphragm to vibrate at a specific frequency and amplitude. Instead of causing air molecules to vibrate as a speaker does, the diaphragm causes the water molecules in the bath to vibrate.
To illustrate further, each cleaner has a bath area that is filled with water or water mixed with detergent. At the bottom of the bath, there is a device that makes ultrasonic waves by vibrating up and down thousands of times each second.
The vibrations in the water cause tiny cavities (bubbles) to form, about the size of a red blood cell or bacteria. However, the constant vibrating puts pressure on the cavities—they are rapidly stretched and compressed. This causes the cavities to violently implode, and if they are near a hard surface, turn into jets of liquid traveling at high speeds. An object submerged in the bath is hit by these jets millions of times per second.
On impact the jets dislodge particles like dust and oil from the object, giving it a nice cleaning. The cavities are very small, so despite the millions of collisions, the process is gentle.
This method is often used to clean intricate objects because the cavities are small enough to get into all of the cracks and crevices, cleaning the places that we can’t otherwise reach.
There are many variations of ultrasonic cleaners.
They can be designed to operate at a specific frequency that most efficiently cleans a specific type of surface. For example, higher frequencies create smaller cavities and so are better for cleaning very intricate objects. Some cleaners are designed to use a water-detergent mix to speed up the cleaning process or aid in rinsing and drying. And, of course, cleaners come in different sizes to accommodate objects of different sizes.
What Is The Best Cleaner To Use In An Ultrasonic Cleaner?
Use water-based detergents. Solvent-based cleaners are generally not designed for use in an ultrasonic cleaner and may damage the stainless tank surface in most cases. For instance, solvents with low flash points – below 200˚F, are never recommended for use in an ultrasonic cleaner, plus solvents are unhealthy for humans.
What Can You Clean in An Ultrasonic Cleaner?
Ultrasonic cleaners are often used to clean items that are intricate, delicate, or otherwise can’t be cleaned using traditional means. Here are some examples of household and personal items that can be cleaned in an ultrasonic cleaner.
- delicate jewelry
- surgical instruments
- precious metals and stones
- Children’s toys
- Window blinds
- Lighting fixtures
- Small kitchen appliances
- Dishes and utensils
- Golf clubs
What Are the Benefits of Using an Ultrasonic Cleaner?
ultrasonic cleaning is safe, environmentally conscious, and less abrasive than other types of cleaning. Since it is carried out with water, or water mixed with detergent alone, then it is gentle on your property. Ultrasonic cleaning is beneficial in the following ways:
- Dirt & Grime Removal
If you have household items and personal belongings that have deep-embedded dirt and grime from a home disaster, ultrasonic cleaning has the ability to fully remove it quickly without elbow grease and long hours of scrubbing by hand.
- House Flooding
Flooding causes mold in as little as two days. Ultrasonic cleaning can be used on the water-damaged household items mentioned above to ensure the full removal of mold.
- House Fire
Removing soot and smoke residue can be especially difficult to do, but ultrasonic cleaning safely removes the smell and grime from your damaged household items. This includes items made of metal, plastic, glass, and more.
What You Cannot Put In Ultrasonic Cleaners?
So now there are gemstones that should not be put in ultrasonic cleaners, starting with:
- Fracture Filled Diamonds
- Synthetic Stones
- Diamonds with lots of Inclusions
- Copper Plated Jewelry
- Opal Doublets or Triplets
The reason for this is that most of these gemstones are brittle and they fracture easily while others erode easily when exposed to ultrasonic cleaners.
What To Do With Ultrasonic Cleaners
- Always unplug the unit before draining the solution. Water and electricity do not mix, and the combination can cause the cleaner to overheat and fail. It can also be lethal when the human body is involved with excess splashing.
- Drain the detergent and clean out the tank occasionally. There is dirt that falls off the parts that are cleaned and will settle at the bottom of the tank and may not filter easily through the filtration system. This dampens the ultrasonic waves and makes cleaning less effective. Regularly rinse it with clean, cool water or wipe the tank bottom clean with a rag.
- Change the filtration system’s filters regularly. Change the filters regularly to keep contaminants out of the cleaning detergent. This helps the system do its job better and faster.
Wipe or spray down parts that have heavy, greasy, or loose contamination before placing them in the ultrasonic cleaner if possible.
- Use water-based detergents as your cleaning solution when using the ultrasonic cleaner.
- De-gas new detergent before you begin cleaning parts. The fresh solution will have some gasses—mostly air—trapped in it, and if these dissolved gasses are not removed, it will take the parts longer to get clean while the detergent degasses itself. Degassing is as simple as raising the temperature on the unit to the desired temperature, and operating the cleaner without anything else in it for a short period –at most ten minutes.
What Not To Do With Ultrasonic Cleaners
Ultrasonic cleaners operate under high voltage. So, never mess with the electronic controls, transformer, or transducers on the unit, or try to do your repairs. Do not allow the cleaning solution level to drop more than one inch below the top of the tank.
- Never put any parts of your body into the ultrasonic cleaner while it is operating without proper protection such as thermal gloves and goggles.
- Never use alcohol, gasoline, or flammable solutions. Doing so could cause a fire or explosion. Use only water-based solutions.
- Do not ever use mineral acids. These could damage the tank.
Failure to comply with these cautions will void your warranty.
Decreased cavitation or cleaning action can result if:
- The cleaner is not full enough (always follow directions about how full one should fill the cleaner)
- One is using water or some other cleaning agent that is not intended for use as an ultrasonic cleaning solution. Also, even with a good cleaning solution, the solution has to be degassed by running the cleaner for approximately 10 minutes before use. Otherwise, you will also get decreased cavitation.