Ultrasonic cleaning is a technology that has revolutionized the way in which various items are cleaned. This process involves the use of high frequency sound waves to agitate a liquid, creating tiny bubbles that remove impurities from surfaces in a matter of minutes.
Ultrasonic cleaning can be used in a variety of industries, including healthcare, aerospace, manufacturing, automotive, and semiconductor. While this technology has been around for decades, it continues to be refined and improved, making it an increasingly popular choice for those seeking efficient and effective cleaning solutions.
- Ultrasonic cleaning uses high-frequency sound waves to efficiently remove dirt and contaminants from surfaces.
- Different frequencies are used for different cleaning purposes, from heavy-duty to delicate cleaning applications.
- Ultrasonic cleaning offers advantages such as cleaning complex shapes, reducing cleaning time, and minimizing chemical usage.
- The right cleaning solution composition is crucial for effective cleaning without damaging surfaces.
- To prevent damage, avoid resting objects on the tank bottom, stacking parts, and use baskets or jigs for separation and optimal cleaning.
How Does An Ultrasonic Cleaner Work?
To begin with, an ultrasonic cleaner generates ultrasonic waves by passing an electric current through a transducer. This creates high-frequency sound waves that are transmitted through the cleaning solution.
These waves create a vibration in the liquid that produces small bubbles known as cavitation. The cavitation bubbles oscillate and implode, generating energy that is then transferred to the surrounding liquid. This energy is what ultimately removes dirt and other contaminants from the surface being cleaned.
Water molecules play a critical role in the cavitation process. They are constantly imploding and generating energy, which leads to the evolution of energy water waves that constantly impact the surface of the object to be cleaned. This impact is what strips away attached dirt from the object.
One of the primary benefits of ultrasonic cleaning is its ability to effectively remove contaminants from complex shapes and hard-to-reach areas. Items such as medical instruments, aerospace components, etc. can all be thoroughly cleaned using ultrasonic technology. In addition, ultrasonic cleaning is more efficient than traditional cleaning methods because it requires less time and fewer chemicals.
How Frequency Relates To Ultrasonic Cleaning
Frequency is used to measure cycles per second or vibrations per second. The unit used to measure frequency is Hertz (Hz). For example, if a sound wave vibrates 1 cycle per second, then its frequency is 1 Hz. If it vibrates 20 cycles per second, then its frequency is 20 Hz. Our ears can detect changes in frequency based on the pitch of the sound. Higher frequency sound waves have a higher pitch, while lower frequency sound waves have a lower pitch.
In ultrasonic cleaning, frequencies are used to create high-frequency sound waves that agitate a liquid to produce tiny bubbles known as cavitation. These bubbles implode, releasing energy that removes dirt and other contaminants from surfaces being cleaned. The frequency used in ultrasonic cleaning can range from 15 kHz to 400 kHz. However, frequencies below 20 kHz are usually not effective for cleaning, and frequencies above 100 kHz are typically reserved for delicate parts.
The typical frequency used in ultrasonic cleaning applications falls around 40 kHz. This frequency is chosen because it is effective at removing dirt and other contaminants from surfaces without damaging the item being cleaned. Higher frequencies are used for delicate parts or those that require a gentler cleaning process, while lower frequencies are used for heavy-duty cleaning applications.
One of the main benefits of using ultrasonic technology is that it is incredibly efficient. Ultrasonic cleaning can clean items in a matter of minutes, while traditional cleaning methods may take hours and require harsh chemicals that can damage the item. Additionally, ultrasonic cleaning can effectively remove contaminants from complex shapes and hard-to-reach areas.
Why Ultrasonic Cleaning Frequency Matters
When it comes to ultrasonic cleaning, frequency matters. Different frequencies are used for different purposes and can have a significant impact on the effectiveness of the cleaning process.
At the lowest end of the ultrasonic cleaning frequency range is 25 kHz. This frequency is used with larger mass items that require a little more power to remove surface grime. Examples include cleaning cast iron blocks for injection molding, massive steel cutting tools, and large stainless steel plates.
The vast majority of ultrasonic cleaning machines feature a 40 kHz transducer, which produces mid-sized cavitation bubbles. This frequency is the middle-of-the-road standard and is commonly used for a wide range of cleaning applications. It has enough power to shake contaminants loose without causing damage to the item being cleaned. Common uses for 40 kHz ultrasonic cleaning include removing oils and metal chips from general machine shop applications, soot removal from items damaged in fires, and cleaning ceramics used in high technology fields.
For delicate cleaning applications, higher frequency generators are used. These include 68 kHz, 132 kHz, and 170 kHz ultrasonic cleaning. Such frequencies provide a delicate and thorough cleaning, and are employed in cases where cavitation bubbles need to reach even closer to the substrates being cleaned. Although less common, these ultrasonic cleaning are highly effective at removing the tiniest particles.
Cleaning Solution Best Practices
The success of the cleaning process depends largely on the cleaning solution used.
- Plain water is not an effective cleaning solution for ultrasonic cleaning. The cleaning solution used in ultrasonic cleaning is specifically designed to make the process more effective. The solution contains ingredients that reduce surface tension and increase cavitation levels, such as a good wetting agent or surfactant.
- Aqueous cleaning solutions are commonly used in ultrasonic cleaning and contain detergents, wetting agents, and other components that play a significant role in the cleaning process. The appropriate composition of the solution is highly dependent on the object being cleaned. Solutions are mostly used warm, at about 50–65 °C (122–149 °F) to ensure maximum effectiveness.
- Water-based cleaning solutions are not as effective as solvent solutions in removing contaminants by chemical action alone. For delicate parts covered with thick grease, solvent solutions are often more effective than water-based solutions. Compared to a solvent-based system, designing an efficient aqueous-cleaning system for a particular purpose demands a higher degree of effort.
It is also important to note that HFE 7100 should never be used to fill an ultrasonic tank due to its high solvent loss. It can damage surfaces and cause a risk to the person using the equipment.
How To Avoid Damage During Ultrasonic Cleaning
It is essential to use ultrasonic cleaning carefully to avoid causing damage to the items being cleaned. Here are some tips on how to avoid damage during ultrasonic cleaning:
- To ensure proper cleaning, it is important to prevent objects from resting at the bottom of the ultrasonic tank during the cleaning process. Cavitation, which involves the generation and rupture of small bubbles within the cleaning solution, is unable to take place on areas of an object that are not in contact with the solvent. The lack of cavitation will result in ineffective cleaning and may even cause damage to the item being cleaned.
- Do not stack parts during the cleaning process. Parts must have space around them to allow cavitation to take place evenly and prevent damage from parts vibrating against each other. Stacking parts can lead to uneven cleaning, and the parts may even become stuck together, causing damage.
Additionally, it is advisable to use baskets and jigs to reduce damage and optimize the cleaning process. These tools keep the items separated, ensuring there is no contact between them, and allow for maximum exposure to the cleaning solution.
In conclusion, ultrasonic cleaning technology has revolutionized the cleaning process across various industries. By utilizing high-frequency sound waves, ultrasonic cleaning generates cavitation bubbles that remove impurities from surfaces in a matter of minutes. Ultrasonic cleaning frequencies can range from 15 kHz to 400 kHz, but the common frequency utilized in most ultrasonic cleaning applications is around 40 kHz. Lower frequencies are ideal for heavy-duty cleaning, while higher frequencies are suitable for delicate items.
Ultrasonic cleaning offers numerous benefits, including the ability to clean complex shapes and hard-to-reach areas, reduced cleaning time, and the use of fewer chemicals. However, it is essential to use appropriate cleaning solutions, follow best practices, and take precautions to avoid damage to the items being cleaned.
With ongoing advancements, ultrasonic cleaning continues to evolve as a popular choice for efficient and safe cleaning solutions.
Why PFC Is Your Destination for Ultrasonically Cleaned Components
At Precision Fabricating & Cleaning, our commitment to delivering cleaned components and parts is unmatched. Our ultrasonic cleaning process is designed to get rid of contaminants that may hinder component performance and longevity. Our skilled technicians are equipped with advanced ultrasonic cleaning techniques, ensuring the thorough cleaning of your industrial equipment. Contact us today.