November 8, 2018
Ultrasonic cleaners provide quick and complete cleaning for parts to be plated or coated, saving time and ensuring superior adhesion. The ultrasonic cleaning process leaves bare surfaces free from contaminants, even in hard-to-reach places such as interior cavities and holes. The use of ultrasonic parts cleaners is completely safe and doesn’t require chemicals to soften or dissolve dirt. Benefits include faster processing, higher throughput and better quality output.
Why Use Ultrasonic Cleaning with Plating or Coating?
Parts to be plated or coated, such as parts made from metal or plastic, often have surface contaminants that must be removed before the plating or coating process can take place successfully. If impurities are left on the surfaces, the covering material often will not adhere to the parts and the quality of the product and its appearance will suffer.
Typical contaminants are residues from machining, buffing compound and shop dirt. Traditional cleaning methods include soaking in chemicals, manual scrubbing and washing. These methods are time-consuming and often don’t remove all contaminants in hard-to-reach places. Ultrasonic parts cleaners remove all contaminants down to the bare surfaces everywhere on the parts to be plated or coated, even from inaccessible areas such as interior openings or crevices. Cleaning is fast and complete.
How Ultrasonic Cleaning Before Plating or Coating Works
Ultrasonic cleaning systems work by producing microscopic cavitation bubbles in the cleaning tank. An ultrasonic generator delivers the high-frequency electric signal to a transducer immersed in the cleaning solution. The transducer has a surface that vibrates at the ultrasonic frequency and creates the ultrasonic waves in the liquid.
Ultrasonic waves in a liquid have high-pressure peaks and low-pressure troughs. Cavitation bubbles are created at low pressure and they collapse in the high-pressure peaks. The continuous cavitation action results in a strong scrubbing effect on the surfaces of the parts to be cleaned. Contaminating material and particles are dislodged and carried away by the cleaning solution. The process depends on the type of contaminant and how much has to be removed but cleaning is often complete after ten to twenty minutes.
Choosing the correct frequency, power and type of transducer is important for effective cleaning before plating or coating. The frequency depends on the structure of the parts and the nature of the contamination. The manufacture of some parts results in surfaces coated with heavy, oily or greasy material while other parts only have a light coating of powder or dirt. The parts themselves may be robust and rugged or delicate and easily damaged. Choosing the right ultrasonic frequency takes these factors into account.
Low frequencies such as 26 kHz or 38 kHz generate comparatively large bubbles that deliver strong, aggressive cleaning power suitable for heavy contamination of robust parts. Lighter contamination on more delicate parts can use higher frequencies with smaller bubbles and softer cleaning action. For the more delicate parts, higher frequencies in the 160 kHz to 200 kHz range deliver gentle cleaning. No matter what kind of part and what contaminants, ultrasonic cleaners can be configured with one or more frequencies that will deliver excellent cleaning performance prior to plating or coating.
Once the frequencies are determined, the power has to be adequate to fill the cleaning tank with ultrasonic waves. With adequate power, bubbles and cleaning action will appear wherever cleaning solution is present. Transducers can be built in, such as in turnkey systems, bolt on or immersible. The independent immersible units are especially flexible and can be easily be used in existing tanks, for example, if there is an existing plating or coating line with cleaning tanks already integrated.
Kaijo’s ultrasonic parts cleaners can effectively be used with any plating or coating application. In addition Kaijo will help customers select a system that will provide optimum performance to meet their specific cleaning requirements.
June 29, 2016
Ultrasonic cleaners work by generating ultrasonic acoustic waves into a cleaning solution. During the expansion phase of the wave, the low pressure results in cavitation bubbles in the liquid while the subsequent compression phase collapses the bubbles suddenly. This bubble action removes impurities and contamination from surfaces to be cleaned. Ultrasonic parts cleaners are fast and cost-effective, eliminating the use of harsh chemicals and the mechanical scrubbing required for traditional cleaning solutions.
Low frequency cleaners using ultrasonic frequencies of 26 kHz or 38 kHz use a much longer wavelength than high frequency cleaning systems operating above 200 kHz or in the MHz range. With a lower frequency and longer wavelength, there is more time for the bubbles to grow and the energy with which they collapse is higher. At the highest frequencies the bubbles are very small and the cleaning action from the collapse of the bubbles is very gentle. While cleaning intensity is controlled by the frequency, the number of bubbles depends on the power of the ultrasonic parts cleaner. High power units work faster and can handle larger parts while low power cleaners are for small systems.
Low Frequency Ultrasonic Parts Cleaners for Robust Cleaning
Kaijo ultrasonic cleaning systems such as those using the Phenix III ultrasonic generator operate at 26 kHz or 38 kHz and are suited for the cleaning of robust parts with stable surfaces. If an ultrasonic parts cleaner is used for parts that are not suitable, surface pitting can result and the parts may be damaged. Systems based on the Phenix III are suitable for cleaning machined parts, ceramics, glass, medical devices and jewelry. The generator is available with outputs of 600 W and 1200 W for cleaning parts of different sizes and the corresponding tanks can hold small or large parts.
Systems such as those based on the Phenix III generator are suitable for general purpose cleaning in a manufacturing environment that does not deal with delicate parts. An ultrasonic parts cleaner suitable for a wide variety of applications, the flexible Phenix III is a cost effective and reliable solution. It can be purchased as an immersible set for an existing tank or in a turnkey configuration with Kaijo transducers and tanks designed specifically to work with the ultrasonic generator.
High Frequency Cleaning for Delicate Parts
High frequency ultrasonic cleaners are used for parts that could be damaged by the robust bubble action present at 26 kHz and 38 kHz and for light surface contamination. Frequencies up to the MHz range can clean parts such as printed circuits, semiconductor components, optical components and precision-machined parts. The cleaning action is powerful enough to remove surface films and particles down to sub-micron sizes but gentle enough so that relatively soft surfaces and microscopic details are not affected.
Ultrasonic cleaners such as the Kaijo Quava models can generate a wide variety of frequencies and powers to deliver the specific cleaning intensity and power required for a particular application. Decision makers and production managers in manufacturing plants that have part cleaning requirements have to decide whether to purchase a low-frequency all-purpose ultrasonic parts cleaner for robust cleaning, a high-frequency model if only delicate parts are to be cleaned, or a general purpose parts cleaner able to generate both low and high frequencies. Kaijo’s ultrasonic parts cleaners are available to cover all these needs. If you need more information on any of Kaijo’s products and want a quote call 408-675-5575 or email [email protected].